Diagnose my poor track times... part 2

[Ttype6]

I agree with that. Especially if the car is pulling timing. 121 is not too far off for an 11.1 pass. If it MPH more in the past it's probably being lost in the KR. However, let's call a horse a horse. The car should have quite a few tenths and MPH just from the 60ft. A 1/4 mile run is incremental and the first 60 feet contribute to the wheel speed and engine RPM it takes to obtain the most E.T and MPH the car is capable of.

An improvement in 60 foot times will do nothing to change the fact that his engine has some kind of problem and is down on power. In his case an improvement in 60 foot will absolutely improve elapsed time,but it will have no effect on MPH which is a reflection of power being made by the engine. Until the engine makes more power,the MPH will remain the same.

 

[RED LS1]

I wasn't arguing that his motor being down on power wouldn't kill MPH.I agree it would. Even if the run was perfect starting at the 60 (which it isn't) losing power from KR will effect MPH.

The fact is, the 60Ft is bad. In the grand scheme of things that is and will be a major contributing factor to getting the MPH back to see true potential of the car. You may gain some MPH from reducing the KR. You may gain another few MPH from reducing .3 in the 60ft along with the missing E.T.

 

[Ttype6]

losing power from KR will effect MPH.

You say here that loss of power WILL lower MPH.

You may gain some MPH from reducing the KR.

You then state here that the restoration of power MIGHT increase MPH.

The fact is, the 60Ft is bad. In the grand scheme of things that is and will be a major contributing factor to getting the MPH back

Then you state here that lower 60 foot times will have the most effect on increasing MPH back to where it used to be.
So,to sum up what you've stated,loss of power reduces MPH and the best way to get the MPH back is to lower 60 ft. times.
I say the best way to get the MPH back is to restore the lost power.

 

[RED LS1]

I'm not sure what your problem is. I have agreed 5 times that reducing KR will increase MPH. I also added to this topic that the car has a poor 60ft which needs to be addressed.

I don't care how much MPH you gain from 0 KR, you will get more on top of that by reducing the 60ft.

 

[JDSfastGN]

haha Alright guys yes the 60 ft does need improvement as well. There are two major contributing factors to that.... but I know the reasons for the poor 60 ft.
1. Terrible suspension geometry in the rear due to the car being very very low. Lower control arm relocation brackets are not an option due to the wheel offsets from the frame notch setting the wheel further in towards the control arm/shock mount.

2. Old slicks

3. And this is a big one. I do not have a first gear off the brake, it is short shifting the 1-2 9 times out of 10 and so its almost a 10 psi 2nd gear start. This may effect a tiny bit of overall mph as well but its the crappy gains on the back half of the track that worry me, combined with the calculated slippage. I need to figure out the knock first and worry about the power and then work on getting the suspension a bit better situated.

 

[JDSfastGN]

A compression test might reveal something. Do you know what valve springs you have and their installed height?
Do you know what your lifter preload is?

I installed the springs (Kmotion K750s) last fall before the last buick vs ford shootout and had them tested before I installed them at the correct height (I don't remember off hand now what that was) I did a compression check last November after the poor mph last year and got consistant results other than 1 cylinder that was a bit higher (160 vs 140 for the rest) This is due to a bit of oil in the cylinder.

Again... Ring seal going away and oil in the cyl causing knock??
A data log of crankcase psi when new and monitored as the miles stack up, could indicate the seal going away.
Just a tip I learned from WJ....

This very well may be and a leak down will be performed sometime very soon. The plugs look good and have no oil contamination and the car never smokes or blows much out of the breathers (at least not more than any other GN) I do have either a leaky guide or seal on the #6 as I saw a bit of oil in the exhaust runner when I had the headers off.

 

[Ttype6]

haha Alright guys yes the 60 ft does need improvement as well. There are two major contributing factors to that.... but I know the reasons for the poor 60 ft.
1. Terrible suspension geometry in the rear due to the car being very very low. Lower control arm relocation brackets are not an option due to the wheel offsets from the frame notch setting the wheel further in towards the control arm/shock mount.

2. Old slicks

3. And this is a big one. I do not have a first gear off the brake, it is short shifting the 1-2 9 times out of 10 and so its almost a 10 psi 2nd gear start. This may effect a tiny bit of overall mph as well but its the crappy gains on the back half of the track that worry me, combined with the calculated slippage. I need to figure out the knock first and worry about the power and then work on getting the suspension a bit better situated.

It's easy to see,from your posted best ET and MPH,that you had a slow 60 ft. issue then. The only thing that has changed is your power output. When you restore the lost power,it will be easily felt and will probably cause a big smile to come to your face.

 

[RED LS1]

Car probably has a 10.50 in it after all the bugs worked out. KR and 60ft both.

 

[JDSfastGN]

Just wanted to update, new knock sensor and ESC module did not fix the issue. I ended up talking with Dusty Bradford today while ordering a converter for a customer and he mentioned ignition. I really hadn't thought a lot about it due to the car not popping and seemingly running smooth and pulling to the desired rpm. But just to check it out I came home tonight and decided to do the normal ohm test and low and behold the middle two coil towers show a broken connection. The other towers ohmed at 11.5k. Ive never had a coil go bad and have the car act like this. My dad has a spare brand new AC coil that I am picking up from him tomorrow. I don't know if this could be causing a false knock but it would certainly explain why the car didn't like an a/f ratio below 10.6. Thanks Dusty. Sometimes it takes an outsider to say something that slaps you in the face. Ill keep this updated.

 

[Ed Valvo]

I hope that's it. If not, check the oil issue. We had a car plagued by KR and found it was sucking in oil.

 

[JDSfastGN]

Well I had a spare coil up at my parents and had my dad bring it into town. I thought it was a delco but it was a magnavox unit. It ohmed at 12k and I put it on. The car ran very very smooth. I took it on a quick trip. The one time I got into the throttle it spun badly but felt strong. It died shortly there after with a blown cci ign fuse. Replaced the fuse and limped it hom on 4 cylinders. This is what I found.

So I ordered a new delco this time since I had some store credit at highway stars anyway. The module is not melted or anything so hopefully it's not fried as well.

 

[Mr.Spool]

test the module as well I hate guessing.

 

[bison]

Ohming can only rule out a coil as no good. It can't confirm it is good. Id test the coil with a known good module. Seeing the spark is a better indicator of the condition of the coil. Carefully do one coil at a time holding the plug wire about an inch from the post. Id also Hotwire the ignition, clean up the grounds and make sure the negative cable is in good shape and retained properly to the front of the block


BPE2013@hotmail.com

 

[TurboTnZ06]

The CCCI fuse will blow when the electrical tabs in the module are not flat after swapping coil packs, need to push them back down into the goo horizontally.

 

[JDSfastGN]

I am going to order a caspers ignition module/coil tester as well to make sure the module is good and its just a nice tool to have. The new coil that I installed yesterday had a random short that created an arc that made the crack in the top of the coil. Those two towers no longer ohm and show to be open so its shot. Bison great advice and I will hotwire the ignition. I really do think this was a fluke bad coil that is just a bump in the road in my diagnosing. TurboTNZ06 I did press them pretty flat and they left slight indentions in the modules goo. We will see how it goes with the new coil when it arrives. Before the new coil shorted I hit it at 45 mph and despite the tire spin I only showed a quick blip of 2* of knock which for my car is a good sign. Thanks guys

 

[bison]

I am going to order a caspers ignition module/coil tester as well to make sure the module is good and its just a nice tool to have. The new coil that I installed yesterday had a random short that created an arc that made the crack in the top of the coil. Those two towers no longer ohm and show to be open so its shot. Bison great advice and I will hotwire the ignition. I really do think this was a fluke bad coil that is just a bump in the road in my diagnosing. TurboTNZ06 I did press them pretty flat and they left slight indentions in the modules goo. We will see how it goes with the new coil when it arrives. Before the new coil shorted I hit it at 45 mph and despite the tire spin I only showed a quick blip of 2* of knock which for my car is a good sign. Thanks guys

It's worth insulating those terminals with heat shrink or good electrical tape also to minimize shorting possibility


BPE2013@hotmail.com

 

[we4Mateo]

The ignition module hotwire greatly increased the life of my coil packs/modules. I went through at least one coil per year, 10k miles, before and the unit I took off before going tr6 was two years old but always hotwired and is still in use on my buddies car.

 

[BARRACUDA1968]

Dumb question but what do you do to hotwire it?

 

[we4Mateo]

Dumb question but what do you do to hotwire it?

Caspers sells a kit but you can make one too. Just run a relay to the ignition module harness. Switched wire from harness fires the relay and relay supplies power. I believe it's the pink wire and I don't remember the switch wire color but there are instructions out there if you don't get the caspers kit. I hotwired: fuel pump, headlights, fans, ignition module, and did the field fix on the alternator. Anything to remove the load from the factory wiring.

 

[BARRACUDA1968]

Thanks for the info!