Hell yeah man. Glad it’s starting to really come together
Building a 7sec 87GN Drag-n-Drive car with V6 Stage 1 heads!
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It has been awhile since I updated this thread it was a pretty busy 2025 so I will try to bring this thread up to date with all the changes.
It's a been a journey for sure and we have been going at it pretty hard for the last 3 years and I need to give it a rest. Unfortunately we will not be at Sick Week this year and won't have the time to do much before May/June of this year. Which means I have a really good chance of actually making it to Bowling Green with a running car! The GN is completely together, running and ready to go and I am not planning to do anything with till then so it has a shot of making BG! The decision is based on my work and time commitments, right now I need to focus on my business and recent changes I am making to secure my future and possible semi-retirement in the next 3 years. Plus I am totally disgusted with my weight and how out of shape I have become so I am making a commitment to get back in shape to at least do a short distance tri this spring. Which means I have to start swimming again, I hate swimming lol!!
To pick up where I left off which was right after Sick at the Rock in April. We went to Sick at the Rock with the car EXACTLY like it was at Sick Week same tune, injectors everything which as you remember also left us dead on the side of the road in a swamp at night in the middle of Florida. The car ran great at Rockingham but I was not happy with a few things and decided to change the injectors to the AFIS 250's and also go to a Holley Injector driver box. I also cleaned up the dash and finally made a panel to go behind the holley dash since I no longer run the factory one.
We went back to the dyno and made a bunch of pullls and REALLY dialed in fueling and the EGT's, we also found a bunch of power and found that the little V6 really like fuel, alot of it. We dropped target AFR from 11:1 to 10:8 and picked up something like 15 horsepower which was significant with no other changes, We balanced the injectors and got the plug readings close, and also tested Renegade E112 vs VP C85 and saw zero difference. We were just testing and really didnt make any hero runs, plus it was a MD dyno which really hurts feeling lol. I forget what it made TBH.
After the dyno we loaded up the car and went to the B3R event at DW42, it s a mini DnD deal and we figured we would get some good test passes and data to get ready for BG which was the following week. The whole event was a disaster, we had nothing but issues some car related most self-inflicted. I got one decent hit on the car with a 5.22@134 with easy launch low boost and I come to find out the traction control was yanking 2-5 degrees the entire pass. Everything was just a mess after that including the drive which we made a bunch of miscalculated mistakes. The car made the 75 mile drive with no issues considering the drive was supposed to only be 50 miles!!!
Once we FINALLY made it back we missed the deadline and were DQ'ed, we pulled in as soon as the first pair were staging. We decided to make a couple test hits to get some data and maybe a good pass. Had had fuel issues since we mixed in some pump gas on the drive. I fixed that and made another easy pass running a 5.2x something. I started to look over the data log and my heart sank when I saw the oil pressure graph. At idle we had 55psi at the top of 1st it was 40 and by the end of the run it was 35 but back at the trailer at idle we still had 50 and there was not indication anything was wrong. I knew since I had the motor apart last fall we had a main bearing clearance issue and BMS forged crank that was WAY to flexy and WELL beyond the power level we should be running it. I knew when I saw the graph we had no main bearings left in the motor. Initially we thought we would get away with rolling a new set of mains in and still making BG. Especially since the car was running great and not making any noises. But we were wrong and the damage was pretty extensive.
When we dropped the #3 main cap we couldn't believe it ran and there was no major destruction!
When Ray first looked at the bearings he thought the one in the cap looked better than the one in the block which was down to the copper. I said look again Ray the one in the cap is just a steel shell!! There is a tiny bit of copper left on the edges if you look lol! The crank was toast it actually had torsional cracks in it around the oil holes and heat related damage to #3 main and #4 rod journals. The #2 main was not pretty either but #1 and #4 mains weren't pretty but did have bearing material left on them. The rest of the motor outside #4 rod bearing was fine. The crank simply had to much flex and not enough bearing clearance. In retrospect we made 1315 rwhp on a Hub dyno and made over 50 high power pulls on this motor with a crank that should have never been in there to begin with. It was an early rough finish BMS forging not one of the later smooth finish forgings which were a lot stronger and I believe 4340 and this one was 4140? She was a trooper thought lol! FYI Belt drive oil pump FTW!!
At this point we are back to the drawing board and obviously out for BG. I had plans for HRDW at this point since I got an invite back but we needed a plan to fix this issue.
The first issue was the crank the BMS one I had was TOAST but I had a complete rotating assembly with Crower billet crank, rods and a set of race tech pistons from my original motor which broke the timing gear in MI. All I needed to do was freshen this block and put it back together and the billert crower crank is going to have siginficantly less flex than the BMS crank.
Main bearings also also another issue at most I can get .0028-.003 with Sealed Power M107's. Clevite no longer makes the H-series main bearings and the P-bearings are to tight usually in the .0025-28 range. King makes a really nice tri-metal coated bearing MB5737XP and they make them in an X size but that are also made of unobtanium!
The last and biggest issue was a mid-plate. We were just runnign HR poly mounts and really need to have a mid-plate in the car. It took some time to figure out but we made it work. We originally though we would only be able to attach it to the drivers side frame but managed to get both sides even with the factory crossover and 4" downpipe.
In the meantime I also added another bullet to the arsenal!
Beleive it or not I actually owned this motor before and got it back of the guy I sold it from. It came as a complete motor but I am only using the short block. I some of the parts from this motor may also be for sale as parts or even a complete motor with an iron block. I have big plans for the aluminum short block which will be the topic of the next post which I will make soon since I can only post 10 pics at a time.
It's a been a journey for sure and we have been going at it pretty hard for the last 3 years and I need to give it a rest. Unfortunately we will not be at Sick Week this year and won't have the time to do much before May/June of this year. Which means I have a really good chance of actually making it to Bowling Green with a running car! The GN is completely together, running and ready to go and I am not planning to do anything with till then so it has a shot of making BG! The decision is based on my work and time commitments, right now I need to focus on my business and recent changes I am making to secure my future and possible semi-retirement in the next 3 years. Plus I am totally disgusted with my weight and how out of shape I have become so I am making a commitment to get back in shape to at least do a short distance tri this spring. Which means I have to start swimming again, I hate swimming lol!!
To pick up where I left off which was right after Sick at the Rock in April. We went to Sick at the Rock with the car EXACTLY like it was at Sick Week same tune, injectors everything which as you remember also left us dead on the side of the road in a swamp at night in the middle of Florida. The car ran great at Rockingham but I was not happy with a few things and decided to change the injectors to the AFIS 250's and also go to a Holley Injector driver box. I also cleaned up the dash and finally made a panel to go behind the holley dash since I no longer run the factory one.
We went back to the dyno and made a bunch of pullls and REALLY dialed in fueling and the EGT's, we also found a bunch of power and found that the little V6 really like fuel, alot of it. We dropped target AFR from 11:1 to 10:8 and picked up something like 15 horsepower which was significant with no other changes, We balanced the injectors and got the plug readings close, and also tested Renegade E112 vs VP C85 and saw zero difference. We were just testing and really didnt make any hero runs, plus it was a MD dyno which really hurts feeling lol. I forget what it made TBH.
After the dyno we loaded up the car and went to the B3R event at DW42, it s a mini DnD deal and we figured we would get some good test passes and data to get ready for BG which was the following week. The whole event was a disaster, we had nothing but issues some car related most self-inflicted. I got one decent hit on the car with a 5.22@134 with easy launch low boost and I come to find out the traction control was yanking 2-5 degrees the entire pass. Everything was just a mess after that including the drive which we made a bunch of miscalculated mistakes. The car made the 75 mile drive with no issues considering the drive was supposed to only be 50 miles!!!
Once we FINALLY made it back we missed the deadline and were DQ'ed, we pulled in as soon as the first pair were staging. We decided to make a couple test hits to get some data and maybe a good pass. Had had fuel issues since we mixed in some pump gas on the drive. I fixed that and made another easy pass running a 5.2x something. I started to look over the data log and my heart sank when I saw the oil pressure graph. At idle we had 55psi at the top of 1st it was 40 and by the end of the run it was 35 but back at the trailer at idle we still had 50 and there was not indication anything was wrong. I knew since I had the motor apart last fall we had a main bearing clearance issue and BMS forged crank that was WAY to flexy and WELL beyond the power level we should be running it. I knew when I saw the graph we had no main bearings left in the motor. Initially we thought we would get away with rolling a new set of mains in and still making BG. Especially since the car was running great and not making any noises. But we were wrong and the damage was pretty extensive.
When we dropped the #3 main cap we couldn't believe it ran and there was no major destruction!
When Ray first looked at the bearings he thought the one in the cap looked better than the one in the block which was down to the copper. I said look again Ray the one in the cap is just a steel shell!! There is a tiny bit of copper left on the edges if you look lol! The crank was toast it actually had torsional cracks in it around the oil holes and heat related damage to #3 main and #4 rod journals. The #2 main was not pretty either but #1 and #4 mains weren't pretty but did have bearing material left on them. The rest of the motor outside #4 rod bearing was fine. The crank simply had to much flex and not enough bearing clearance. In retrospect we made 1315 rwhp on a Hub dyno and made over 50 high power pulls on this motor with a crank that should have never been in there to begin with. It was an early rough finish BMS forging not one of the later smooth finish forgings which were a lot stronger and I believe 4340 and this one was 4140? She was a trooper thought lol! FYI Belt drive oil pump FTW!!
At this point we are back to the drawing board and obviously out for BG. I had plans for HRDW at this point since I got an invite back but we needed a plan to fix this issue.
The first issue was the crank the BMS one I had was TOAST but I had a complete rotating assembly with Crower billet crank, rods and a set of race tech pistons from my original motor which broke the timing gear in MI. All I needed to do was freshen this block and put it back together and the billert crower crank is going to have siginficantly less flex than the BMS crank.
Main bearings also also another issue at most I can get .0028-.003 with Sealed Power M107's. Clevite no longer makes the H-series main bearings and the P-bearings are to tight usually in the .0025-28 range. King makes a really nice tri-metal coated bearing MB5737XP and they make them in an X size but that are also made of unobtanium!
The last and biggest issue was a mid-plate. We were just runnign HR poly mounts and really need to have a mid-plate in the car. It took some time to figure out but we made it work. We originally though we would only be able to attach it to the drivers side frame but managed to get both sides even with the factory crossover and 4" downpipe.
In the meantime I also added another bullet to the arsenal!
Beleive it or not I actually owned this motor before and got it back of the guy I sold it from. It came as a complete motor but I am only using the short block. I some of the parts from this motor may also be for sale as parts or even a complete motor with an iron block. I have big plans for the aluminum short block which will be the topic of the next post which I will make soon since I can only post 10 pics at a time.
- Joined
- Jun 18, 2001
- Messages
- 1,513
I had been debating a turbo swap for some time and wanted to put on one of the new HPT F4 units, but they still have not released anything as of today. The Bullseye NLX88 midframe is a nice turbo and will make a lot of power but just seemed to be a mis-match for my motor combo, especially down low. If you recall all the issues with had with cam timing and TQ at HRDW in 24, a lot of this was the result of a turbo that needed a lot more low end TQ to get moving but once it does it makes a lot of power. According to Harry had to do with the turbine wheel to compressor wheel ratio. While this turbo was an 88mm inducer it has an absolutely mammoth 142mm exducer wheel which Harry had indicated can be the issue and the turbo would be a better match for a TT BBC set up which is what most of these end up on.
On the HUB dyno it made 1315 at 45psi and it honestly had another 100-150hp in it at 50-55 psi. Backpressure, turbo outlet temps and IAT all indicated we weren't even close to tapping out this turbo. On the hub dyno we were making 1/8 mile pulls through all three gears and we made at least 3 at around 1300 at that point I was seriously waiting for the crank to leave the chat. We also went to a smaller cam to make this combo work giving up 6 degrees of duration on the intake lobe and tightening up the LSA to 113.5 which increased overlap to also help the issue. It did work and worked well making over 200 more HP down low while only giving up 40 at peak power at same boost level.
We never got the point of being able to run the car at this power level on the track. Even on the HUB dyno we were starting to blow through the converter. At Sick week we had a good test day the first day but it was a total shit show after that ending with us stuck in a swamp and the injectors locked up. We were able to get after it at Rockingham and were we had a FANTASTIC track and conditions. We ran a 5.15 at 38-9 psi and turned it up to 40-1 and went slower with a 5.18 and the RPM graph looked like a straight line as it was murdering the TQ conv. The difference between 40psi and 45psi on the dyno was not small either it was close to 150rwhp but it was obvious the TQ was not going to work. After Rockingham we swapped stators back to 17 blade along with the injector swap. On the dyno we actually picked up close to 50rwhp in cleaning up fueling and EGTs and thought we were really ready to roll until the main bearings gave up the ghost. By May we had just wore the damn thing out lol.
While the motor was down I decided to make a turbo swap and also maybe take a stab at some class racing with the up and coming Limited 235 class in the Radial Outlaw series. I purchased the spec FIS 76mm turbo they listed in the rules for the class. On paper it looked like it would be an easy swap on my car. It had the same turbine wheel, the BW S400 96x88 turbine wheel, with same 4" vband DP discharge and 3" Vband inlet. Easy peasy right NOT, I never realize how many different size 3 and 4" vband clamps these stupid turbo manufacturers make!
As you can see in the pic the FIS is a little longer than the NLX88. It is because is uses a custom billet center that has the GT55 bearing setup so it is a very robust piece. I had to have Coach (Donnie) modify the turbine inlet to fit the header flange which he was able to pull off and we ended up making a new aluminum downpipe to now match the rest of the aluminum exhaust.
Ray also had to make a new turbo outlet boost tube due to the turbo being longer but he knocked it out of the park as usual
I got the car back together and we went back to the dyno, we knew after the first pull this turbo was a better match. At 25 psi we made as much power as power as it took back in May with the 88mm did at 30. At 32 psi the FIS 76mm turbo was up over 70hp over the 88mm, oh boy this is getting exciting! At 34psi it maxed out at 1192, at 36psi it was down 40 with turbo outlet temps skyrocketing up to a blistering 460 and the backpressure shot up 30 psi to 68psi from 45 at 34psi of boost. That was all she wrote for that turbo! We did play around with the fueling some more and at this point I can honestly say I never had one tuned this well. Everything looked great it was making great power and now all we needed to do was get it on the track and see what it does.
I made it to a QRC track rental Sept 12th the weekend DW was supposed to start. We decided to skip the event and set our eyes on Sick Week again to go back and finish that damn race. So we went testing. The difference in the 76mm turbo vs the 88mm was immediate. We couldn't leave at more than 10psi and 4600rpm but ended up getting the car to run its best 60' with a 1.19. Still soft but WAY better than before, previous best was a 1.21 with 18psi and 5k rpm with the 88. HUGE difference. The track prep was sketch at this rental so we were limited on what we could do, the first 60' was well prepped but after that I relied heavily on the Davis TC to make it the rest of the way. I still had the 275's on it and hadn't switched to the lil 235's. Our last good pass was a 1.19 60' with a 5.22 riding the same TC curve from May pulling 2-5 degrees of timing out the entire pass. I ran the same ET due to the Davis box both times but the difference was huge and so were the differences on the datalogs which were nearly identical due to the Davis box. With the 88mm in May I needed 38-9 psi to make that identical pass, with 5k 18psi launch. WIth the 76mm it was a 4600rpm and 10psi with 33-4 psi going down the track.
Man at this point we are pretty excited and start making plans. Since we ditched HRDW we made plans to do the Cadillac Attack/Buick event at DW42 which was in a couple fo weeks. We figured we could have some fun and get some good testing in and be ready for Sick Week. I had made it so I could swap back to the 88mm turbo if need be but right now I feel the car has enough to go 5.00's with this 76mm turbo as it sits which is in full DnD trim with the GV at 3450# 225# over weight for limited 235! Granted we are still on the 275s but I have the 235s on the trailer along with another set of beadlock wheels from Mac Fab I plan to put on at DW42.
And I am out of picture space again and time so we will need one more post to wrap up 2025......
On the HUB dyno it made 1315 at 45psi and it honestly had another 100-150hp in it at 50-55 psi. Backpressure, turbo outlet temps and IAT all indicated we weren't even close to tapping out this turbo. On the hub dyno we were making 1/8 mile pulls through all three gears and we made at least 3 at around 1300 at that point I was seriously waiting for the crank to leave the chat. We also went to a smaller cam to make this combo work giving up 6 degrees of duration on the intake lobe and tightening up the LSA to 113.5 which increased overlap to also help the issue. It did work and worked well making over 200 more HP down low while only giving up 40 at peak power at same boost level.
We never got the point of being able to run the car at this power level on the track. Even on the HUB dyno we were starting to blow through the converter. At Sick week we had a good test day the first day but it was a total shit show after that ending with us stuck in a swamp and the injectors locked up. We were able to get after it at Rockingham and were we had a FANTASTIC track and conditions. We ran a 5.15 at 38-9 psi and turned it up to 40-1 and went slower with a 5.18 and the RPM graph looked like a straight line as it was murdering the TQ conv. The difference between 40psi and 45psi on the dyno was not small either it was close to 150rwhp but it was obvious the TQ was not going to work. After Rockingham we swapped stators back to 17 blade along with the injector swap. On the dyno we actually picked up close to 50rwhp in cleaning up fueling and EGTs and thought we were really ready to roll until the main bearings gave up the ghost. By May we had just wore the damn thing out lol.
While the motor was down I decided to make a turbo swap and also maybe take a stab at some class racing with the up and coming Limited 235 class in the Radial Outlaw series. I purchased the spec FIS 76mm turbo they listed in the rules for the class. On paper it looked like it would be an easy swap on my car. It had the same turbine wheel, the BW S400 96x88 turbine wheel, with same 4" vband DP discharge and 3" Vband inlet. Easy peasy right NOT, I never realize how many different size 3 and 4" vband clamps these stupid turbo manufacturers make!
As you can see in the pic the FIS is a little longer than the NLX88. It is because is uses a custom billet center that has the GT55 bearing setup so it is a very robust piece. I had to have Coach (Donnie) modify the turbine inlet to fit the header flange which he was able to pull off and we ended up making a new aluminum downpipe to now match the rest of the aluminum exhaust.
Ray also had to make a new turbo outlet boost tube due to the turbo being longer but he knocked it out of the park as usual
I got the car back together and we went back to the dyno, we knew after the first pull this turbo was a better match. At 25 psi we made as much power as power as it took back in May with the 88mm did at 30. At 32 psi the FIS 76mm turbo was up over 70hp over the 88mm, oh boy this is getting exciting! At 34psi it maxed out at 1192, at 36psi it was down 40 with turbo outlet temps skyrocketing up to a blistering 460 and the backpressure shot up 30 psi to 68psi from 45 at 34psi of boost. That was all she wrote for that turbo! We did play around with the fueling some more and at this point I can honestly say I never had one tuned this well. Everything looked great it was making great power and now all we needed to do was get it on the track and see what it does.
I made it to a QRC track rental Sept 12th the weekend DW was supposed to start. We decided to skip the event and set our eyes on Sick Week again to go back and finish that damn race. So we went testing. The difference in the 76mm turbo vs the 88mm was immediate. We couldn't leave at more than 10psi and 4600rpm but ended up getting the car to run its best 60' with a 1.19. Still soft but WAY better than before, previous best was a 1.21 with 18psi and 5k rpm with the 88. HUGE difference. The track prep was sketch at this rental so we were limited on what we could do, the first 60' was well prepped but after that I relied heavily on the Davis TC to make it the rest of the way. I still had the 275's on it and hadn't switched to the lil 235's. Our last good pass was a 1.19 60' with a 5.22 riding the same TC curve from May pulling 2-5 degrees of timing out the entire pass. I ran the same ET due to the Davis box both times but the difference was huge and so were the differences on the datalogs which were nearly identical due to the Davis box. With the 88mm in May I needed 38-9 psi to make that identical pass, with 5k 18psi launch. WIth the 76mm it was a 4600rpm and 10psi with 33-4 psi going down the track.
Man at this point we are pretty excited and start making plans. Since we ditched HRDW we made plans to do the Cadillac Attack/Buick event at DW42 which was in a couple fo weeks. We figured we could have some fun and get some good testing in and be ready for Sick Week. I had made it so I could swap back to the 88mm turbo if need be but right now I feel the car has enough to go 5.00's with this 76mm turbo as it sits which is in full DnD trim with the GV at 3450# 225# over weight for limited 235! Granted we are still on the 275s but I have the 235s on the trailer along with another set of beadlock wheels from Mac Fab I plan to put on at DW42.
And I am out of picture space again and time so we will need one more post to wrap up 2025......
- Joined
- Jun 18, 2001
- Messages
- 1,513
We showed up at DW42 Friday for the Buick event and I don't know what it is with racing but it is once again we are on the shit show express and I didn't even take the car off the damn trailer since the QCR track rental!!!
As soon as we unloaded the car it was leaking water which we came to discover was a steel soft plug that had rusted through. After a few bad ideas with RTV and JB Weld we rode out to the parts store and pick up some stop leak which solved the problem.
We decided to race the TSO class more so for the track prep and its 1/8 mile. This will be the first time this car had been in TSO since 2009. Qualifying was Friday and made 3 passes all a total mess spinning as soon as we let off the brake. We ended the day without a clean pass or any decent data and a mid 6 something qualifying time.
That night at dinner it dawns on me the last time we had this issue we at Sick Week and it was the tires.. So we got to the track early on Saturday and bolted the new 235s on with the new beadlock rims I had Mac Fab do for me.
We put all the changes we made the previous day back to baseline with went up to make a TT pass. We had the balls cut off the starting line tuneup just in case. We had one more qualifying run (or so we thought) and wanted to make a test hit early. I forget what it 60' but it was soft and it only ran a 5.73...with the CO2 bottle off,...ugh. We leave the car as it was and turn the CO2 bottle on for what should be Q4 and boom it dead hooks with an easy 1.24 and 5.18@136! Man are we excited! The car is still in DnD trim GV overdrive and all at 3450#!! We are the heaviest TSO car with the smallest turbo and smallest tires lol!
We are now into round 1 eliminations and somehow I end up as last qualifier when I should have been 3rd. So I end up with Paul in his TSM car which was an easy win but not a cheap one thats for sure! We ran another identical pass to the last with a 5.20@135 1.24 60' for the win but just past the finish line the motor expired. As I pull of the track I notice something is not right and there is smoke everywhere and its not running well. I shut it off unbelt look under the hood nothing obvious, I get the car running again and its not happy and obvious I have at least one man down. I make it over to the scales to make the pass count and back to the trailer. We discover #6 is toast and throw in the towel for another TSO runner up finish. I lost count but I believe this was 5th or maybe 6th time the car and I have been in the finals for a TSO race and lost!
We went over the data on the last pass pretty extensively at the track and found nothing and I mean nothing even remotely wrong or that would indicate something was going wrong. So on the way home I start with all my hypothesis on what happened and come with possibly a blown HG since I had re-used these cometics so many times I lost count. When I went to put the motor back together I second guessed using them again but since I had a custom sized HG it was 6-8 weeks to get new ones so on they went. Unfortunately that wasn't it they held and I still have no issues re-using cometic gaskets multiple times.
The post mortem tear down left us with more questions than answers. The incident happened just beyond the 1/8mile mark when it blew a giant hole in the #6 piston which I found with the bore scope.
It would be a lot easier to explain a torched piston if that was all the damage but it wasn't. It also bent the #6 Billet Crower rod
It be easier to understand if was just one cylinder but it wasnt it also hammered the ring lands on the #5 and #3 pistons and hit #5 so hard it blew out the piston skirts so bad they scuffed the cylinder walls.
To make it even more confusing it happened on separtate cylinder banks one even and two odd cylinders. The car is wired so that 1-3-5 injectors and coils are separate from 2-4-6. We have gone over this a million times at this point and have left no stone unturned in trying to figure it out and still today are left with no definitive answers.
What we do know, the rod bent BEFORE the piston melted and we believe the bent rod caused the piston to get hot and torch. I can see this in the pan vac at halfway through 3rd it jumps from .25psi to .63psi. Not a lot but it moved and of course you can see exactly where the piston let go.
The injectors immediately became suspect #1 for the crime. I sent everthing to AFIS including the injector driver, tune file and datalogs. Eric went through all of it including running everything on the flow bench duplicating the run and still came up with nothing. The #6 injector was the weakest in flow testing but we knew that from the dyno and had an additional 6% of fuel in that cylinder to compensate for it. Maybe the injectors locked OPEN and hydrolocked, after all it made sense and it happened before at Sick Week right? That was with the Billet Atomizer at 2200rpm and NOT with the AFIS injectors and at 7k RPM. The AFIS 250# injector flowing at 100% is not physically capable of flowing enough fuel to cause that to happen. Plus we would have seen it in the EGT and AFR data which we didn't.
Whatever happened only happened on those three cylinders as 1-2-4 all looked like you could put them back in the motor. The plugs even looked fine even #6 which was chewed up but it was from molten alumunum more than anything and to make it really bizarre how did we smash the #5 piston hard enough to blow out the piston skirt and still have an electrode on it??
2-4-6
1-3-5
We have a few therioes at thsi point, first we had 20 degrees of timing in it when we typically have 18. This is because we typically ran the motor at 38-40 psi with the 88mm turbo and we are at 33-34 with the 76mm lower in the timing MAP. That being said we have tested this in the past and ran 18 becuase the motor didnt really like anymore than that. Remember the MIR incident when I accidently put over 30 degrees in the motor and lost ring tension on #1 piston and didnt hurt anything else? I don't think the extra 2 degrees made any significant difference OR caused this issue. Plug gap was .018 and we typically run .016, again an oversight but was it an issue? Never had any indication we were blowing out the spark but IDK.
The last issue we explored is we switchded from Renegade E112 race E85 gas to VP C85 back in May We actually did this since we can buy it at the VP truck on Sick week and wouldn't have to carry race E85 with us on road trip. We did test it against the Renegade and there was less than 3 HP difference between the pulls with NO change in the fuel table. I have come to find out that C85 has NO gas in it and is mixed with MTBE, nitomethane, and alkyloids such as tolulene and xylene which are common octane boosters. It does not separate on a water test and it is typically 80% ethanol content 20% the other stuff.
There are some other issues with race E85 in general that has me questioning if you even need it. It might be better to just run a quality E85 cut with regular gas. Afterall the 15% gas is there to make the ethanol easier to ignite. High octane fuel is actually HARDER to ignite, something to ponder.
So what caused the rod to bend smash the pistons and somehow miss torching the spark plugs? Pre-ignition is the only thing that can cause this other than hydrolocking which was ruled out. This is not the same thing as detonation which occurs after the combustion process. This sucker lit BEFORE the plug and in doing so spiked the cylinder pressure to the moon trashing the motor. What caused it? Not sure probably a combination of things, plug gap to wide, 2 deg extra timing and a fuel I have since become highly suspect of may be the answer but we still truely don't know.
I was able to get the motor back together with the rods and pistons from the BMS crank rotating assembly. I was able to send the piston to line to line to be coated since the bore was now 4.026 and those pistons were originally for a 4.023 bore. I did have to sleeve the #6 hole since we torched the block too which sucks since it was a fairly mint block to start with.
The motor has been back in the car and running since the end of November. I am going to put it back on the dyno to test a few things and check some stuff along with changing fuels which I have not fully decided on what I am going to switch too. I also sent the FIS turbo back to Jose who wanted to make a few tweaks to it since we were out of comrpessor wheel and I would like to see what we get with that. Otherwise we are 3 weeks away from Sick Week and the car is ready to roll but we are not going due to the reasons I mentioned earlier.
I am taking a break and I am ready for it! we tore up 3 motors at this point and I need to take a step back and re-evaluate.
As soon as we unloaded the car it was leaking water which we came to discover was a steel soft plug that had rusted through. After a few bad ideas with RTV and JB Weld we rode out to the parts store and pick up some stop leak which solved the problem.
We decided to race the TSO class more so for the track prep and its 1/8 mile. This will be the first time this car had been in TSO since 2009. Qualifying was Friday and made 3 passes all a total mess spinning as soon as we let off the brake. We ended the day without a clean pass or any decent data and a mid 6 something qualifying time.
That night at dinner it dawns on me the last time we had this issue we at Sick Week and it was the tires.. So we got to the track early on Saturday and bolted the new 235s on with the new beadlock rims I had Mac Fab do for me.
We put all the changes we made the previous day back to baseline with went up to make a TT pass. We had the balls cut off the starting line tuneup just in case. We had one more qualifying run (or so we thought) and wanted to make a test hit early. I forget what it 60' but it was soft and it only ran a 5.73...with the CO2 bottle off,...ugh. We leave the car as it was and turn the CO2 bottle on for what should be Q4 and boom it dead hooks with an easy 1.24 and 5.18@136! Man are we excited! The car is still in DnD trim GV overdrive and all at 3450#!! We are the heaviest TSO car with the smallest turbo and smallest tires lol!
We are now into round 1 eliminations and somehow I end up as last qualifier when I should have been 3rd. So I end up with Paul in his TSM car which was an easy win but not a cheap one thats for sure! We ran another identical pass to the last with a 5.20@135 1.24 60' for the win but just past the finish line the motor expired. As I pull of the track I notice something is not right and there is smoke everywhere and its not running well. I shut it off unbelt look under the hood nothing obvious, I get the car running again and its not happy and obvious I have at least one man down. I make it over to the scales to make the pass count and back to the trailer. We discover #6 is toast and throw in the towel for another TSO runner up finish. I lost count but I believe this was 5th or maybe 6th time the car and I have been in the finals for a TSO race and lost!
We went over the data on the last pass pretty extensively at the track and found nothing and I mean nothing even remotely wrong or that would indicate something was going wrong. So on the way home I start with all my hypothesis on what happened and come with possibly a blown HG since I had re-used these cometics so many times I lost count. When I went to put the motor back together I second guessed using them again but since I had a custom sized HG it was 6-8 weeks to get new ones so on they went. Unfortunately that wasn't it they held and I still have no issues re-using cometic gaskets multiple times.
The post mortem tear down left us with more questions than answers. The incident happened just beyond the 1/8mile mark when it blew a giant hole in the #6 piston which I found with the bore scope.
It would be a lot easier to explain a torched piston if that was all the damage but it wasn't. It also bent the #6 Billet Crower rod
It be easier to understand if was just one cylinder but it wasnt it also hammered the ring lands on the #5 and #3 pistons and hit #5 so hard it blew out the piston skirts so bad they scuffed the cylinder walls.
To make it even more confusing it happened on separtate cylinder banks one even and two odd cylinders. The car is wired so that 1-3-5 injectors and coils are separate from 2-4-6. We have gone over this a million times at this point and have left no stone unturned in trying to figure it out and still today are left with no definitive answers.
What we do know, the rod bent BEFORE the piston melted and we believe the bent rod caused the piston to get hot and torch. I can see this in the pan vac at halfway through 3rd it jumps from .25psi to .63psi. Not a lot but it moved and of course you can see exactly where the piston let go.
The injectors immediately became suspect #1 for the crime. I sent everthing to AFIS including the injector driver, tune file and datalogs. Eric went through all of it including running everything on the flow bench duplicating the run and still came up with nothing. The #6 injector was the weakest in flow testing but we knew that from the dyno and had an additional 6% of fuel in that cylinder to compensate for it. Maybe the injectors locked OPEN and hydrolocked, after all it made sense and it happened before at Sick Week right? That was with the Billet Atomizer at 2200rpm and NOT with the AFIS injectors and at 7k RPM. The AFIS 250# injector flowing at 100% is not physically capable of flowing enough fuel to cause that to happen. Plus we would have seen it in the EGT and AFR data which we didn't.
Whatever happened only happened on those three cylinders as 1-2-4 all looked like you could put them back in the motor. The plugs even looked fine even #6 which was chewed up but it was from molten alumunum more than anything and to make it really bizarre how did we smash the #5 piston hard enough to blow out the piston skirt and still have an electrode on it??
2-4-6
1-3-5
We have a few therioes at thsi point, first we had 20 degrees of timing in it when we typically have 18. This is because we typically ran the motor at 38-40 psi with the 88mm turbo and we are at 33-34 with the 76mm lower in the timing MAP. That being said we have tested this in the past and ran 18 becuase the motor didnt really like anymore than that. Remember the MIR incident when I accidently put over 30 degrees in the motor and lost ring tension on #1 piston and didnt hurt anything else? I don't think the extra 2 degrees made any significant difference OR caused this issue. Plug gap was .018 and we typically run .016, again an oversight but was it an issue? Never had any indication we were blowing out the spark but IDK.
The last issue we explored is we switchded from Renegade E112 race E85 gas to VP C85 back in May We actually did this since we can buy it at the VP truck on Sick week and wouldn't have to carry race E85 with us on road trip. We did test it against the Renegade and there was less than 3 HP difference between the pulls with NO change in the fuel table. I have come to find out that C85 has NO gas in it and is mixed with MTBE, nitomethane, and alkyloids such as tolulene and xylene which are common octane boosters. It does not separate on a water test and it is typically 80% ethanol content 20% the other stuff.
There are some other issues with race E85 in general that has me questioning if you even need it. It might be better to just run a quality E85 cut with regular gas. Afterall the 15% gas is there to make the ethanol easier to ignite. High octane fuel is actually HARDER to ignite, something to ponder.
So what caused the rod to bend smash the pistons and somehow miss torching the spark plugs? Pre-ignition is the only thing that can cause this other than hydrolocking which was ruled out. This is not the same thing as detonation which occurs after the combustion process. This sucker lit BEFORE the plug and in doing so spiked the cylinder pressure to the moon trashing the motor. What caused it? Not sure probably a combination of things, plug gap to wide, 2 deg extra timing and a fuel I have since become highly suspect of may be the answer but we still truely don't know.
I was able to get the motor back together with the rods and pistons from the BMS crank rotating assembly. I was able to send the piston to line to line to be coated since the bore was now 4.026 and those pistons were originally for a 4.023 bore. I did have to sleeve the #6 hole since we torched the block too which sucks since it was a fairly mint block to start with.
The motor has been back in the car and running since the end of November. I am going to put it back on the dyno to test a few things and check some stuff along with changing fuels which I have not fully decided on what I am going to switch too. I also sent the FIS turbo back to Jose who wanted to make a few tweaks to it since we were out of comrpessor wheel and I would like to see what we get with that. Otherwise we are 3 weeks away from Sick Week and the car is ready to roll but we are not going due to the reasons I mentioned earlier.
I am taking a break and I am ready for it! we tore up 3 motors at this point and I need to take a step back and re-evaluate.
- Joined
- Jun 18, 2001
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All the time! Its a DnD car and i believe it has close to 2300 mile on it since Jan of 23. We put close to 900 on it at HRDW in 2024.
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