What's the fastest you've seen done on stock heads/block in a GN?

["Turbo-T"]

Suppose you have a stock headed 3.8 liter, and you're running say 20 psi, with an an aftermarket turbo and maybe an aftermarket I/C....can you even run in the 10's in the 1/4? Or are aftermarket heads required?

After reading this post: http://www.turbobuick.com/forums/general-turbo-buick-tech/328197-10s-17psi.html I didn't want to hijack to ask, so I started my own...seems some think there's a 10 sec pass possible but he's got aftermarket heads.

 

[bison]

fast:biggrin:

 

[Sweet6]

Bone stock longblock is 30lbs with a low 1.5X 60ft. The guy in the thread has a stroker motor with ported heads and decent cam.

 

["Turbo-T"]

Ooops. Missed the "stroker" part he mentioned. :redface: Was thinking he was running a stock bottom end.

 

[notacarlo]

do some reading in the recipe area of GNTTYPE. You will see this has been done waaaaaaaay long ago.

 

[The_Six]

Just do a search for Bison's busted piston thread he was running 10s with a stock long block if I remember correctly when the piston cracked.

 

[KevinB]

When talking stock heads, are you meaning unported? Ported stock heads have been 9.30's. Not sure how fast unported heads have been. I have read about a few cars going high tens with an unopened stock engine. I hope to be one myself with a small Turbo. Problem is I think I'm pretty maxed out as far as my tuning skills are capable of. My time 11.39 is still far away. I'm really going to have to think about how the next .4 seconds are going to be shaved off. I know the stock cam is killing me but I'd like to run the number with it.

 

[jasjamz]

Just do a search for Bison's busted piston thread he was running 10s with a stock long block if I remember correctly when the piston cracked.

No, Bison had a stock SHORT block.

Fastest I went was 12.70@108 22-23psi and I don't know what the timing was. This was in 2001-2002. Car had a Gen 6 DFI. No scanmaster, no alky, or drag radials. Had no idea of what tuning was. All I knew was race gas an 22psi. This was my daily driver at the time, huge subs in the trunk and all and ran that on regular 245/60/15s. I could hot lap it and drive it home after 4 or 5 passes. I wish I had of kept it that way at times.

 

[jasjamz]

When talking stock heads, are you meaning unported? Ported stock heads have been 9.30's. Not sure how fast unported heads have been. I have read about a few cars going high tens with an unopened stock engine. I hope to be one myself with a small Turbo. Problem is I think I'm pretty maxed out as far as my tuning skills are capable of. My time 11.39 is still far away. I'm really going to have to think about how the next .4 seconds are going to be shaved off. I know the stock cam is killing me but I'd like to run the number with it.

1.6 or 1.65 rockers, harder launch, Blue bottle hidden behing the glove box.... I'm just saying you have options

 

[bison]

No, Bison had a stock SHORT block.

Fastest I went was 12.70@108 22-23psi and I don't know what the timing was. This was in 2001-2002. Car had a Gen 6 DFI. No scanmaster, no alky, or drag radials. Had no idea of what tuning was. All I knew was race gas an 22psi. This was my daily driver at the time, huge subs in the trunk and all and ran that on regular 245/60/15s. I could hot lap it and drive it home after 4 or 5 passes. I wish I had of kept it that way at times.

+1. I never felt it necessary to torture the engine with boost to run a number on the stock long block. You need a hell of a fuel system to do so since the boost will be in the mid to high 30's to make 9 sec power. You will need volume at 75-80psi fuel pressure.

 

[KevinB]

1.6 or 1.65 rockers, harder launch, Blue bottle hidden behing the glove box.... I'm just saying you have options

That would mean spending money! LOL. I have a few things I may try. The boost was at 29.5 psi....My iat temps only rose 15 degrees from start to finish(90-105 degrees). May try a few more turns on the rod. I have my TA headers sitting here...not sure if I will gain anything from that. My VE table really shows the stock cam's limitations. At 5K, the number is around .730 on my DFI, at 5200, They go down to .670, at 5400, they go down even more to .640. My trap rpm is 5500. I got the fuel correction down to less than 1% going down the track. I'm also running 26.25 degrees of timing. I made 12 passes Friday...hot lapping it:biggrin: One pass I went from 25 degrees timing to the 26.25 and gained a mph.
Using the TCI calc...my slippage is 5.024 (118.49, 26" tire 255/60, 5500 rpm)..not bad for an OLD art car 200 non/lockup. I'm thinking a 28" tall tire will really help! I wonder if a 28x9 slick would fit good on a stock T wheel?

 

[KevinB]

The TCI cal showed my rpm's going down over 400 if switching from a 26 to a 28" tall tire.

 

[jasjamz]

Bison how much did the car weigh you had the stock short block in? When torn apart did you see signs of the crank flexing or the caps walking?

Kevin, I think that tire will fit. What does the car tip the scales at?

 

[KevinB]

Bison how much did the car weigh you had the stock short block in? When torn apart did you see signs of the crank flexing or the caps walking?

Kevin, I think that tire will fit. What does the car tip the scales at?

I'm right at 3600 with me in it.

 

[bison]

Bison how much did the car weigh you had the stock short block in? When torn apart did you see signs of the crank flexing or the caps walking?

Kevin, I think that tire will fit. What does the car tip the scales at?

It was about 3650lbs. Minimal cap walk and lots of crank flex in the center. Center mains show rubbing on the bearing inserts. This engine never saw any detonation. I still have it sitting mostly together. Ill email you some pics when i get a chance. Keep in mind it went 10.29 with a weakt 60' @28.5psi on its first and only pass. I ran it at 33psi for 3 months after that. It was considerably stronger at 33psi. They live a long time if there is no detonation. When it comes to blowing out the bottom end id be less worried about that than cracking the stock pistons or blowing the stock head gaskets to run 9's on an unopened one. You may have one or two shots at it before you will be leaking compression all over the place with the stock fasteners. With the stock cam you need to have 4 key things to run it really fast once you have a large enough turbo. They are at least c16 and preferably import fuel , a really good converter, enough fuel system to handle the volume at high pressures, and you need to remove gear either via really tall slicks or dropping to a lower numerical number. Id go with a 29" slick, PTC 9.5", A 66-70 GTQ/HPQ, and a double pumper with at least one boost a pump or just go with a totally different fuel system. This is not going to happen on 93 octane for anyone who thinks it could. No f'in way. You will need close to 40psi boost to run 9's and keep the rpm under 5300. That is a lot of fvcking cylinder pressure and it isnt going to last long. You would need something else to get the boost that high. Manifold pressure and the available wastegates by themself would not be enough. Maybe someone will grow some balls and try it soon:biggrin:.

 

[TurboTnZ06]

Ooops. Missed the "stroker" part he mentioned. :redface: Was thinking he was running a stock bottom end.

The only thing stock on that engine is the throttle body, oil dipstick, fuel rail and coil pack

How fast you want to go has a lot to do with fuel/boost/timing used. This summer on my 87 GN I ran 13.0 @ 104 on pump gas (E10 93) max 18.5 psi boost, full tank, with a spare, jack, tools, baby seat in the car- pure street trim. Mods- 60# inj, Adj FP reg, TT chip (I used a 21* chip I think), hotwired Reds XP pump, volt booster, TE44.63, 3" ATR external gate downpipe, forged pistons, M&H racemaster DR's 275 50 17, Zddp. Everything else is stock.

I've since put it back to stock turbo, Kirban 3" stock elbow downpipe and stock airbox to try to run 13.0 on pump gas again while the T goes back under the knife.

 

[Just a Six??]

No, Bison had a stock SHORT block.

Fastest I went was 12.70@108 22-23psi and I don't know what the timing was. This was in 2001-2002. Car had a Gen 6 DFI. No scanmaster, no alky, or drag radials. Had no idea of what tuning was. All I knew was race gas an 22psi. This was my daily driver at the time, huge subs in the trunk and all and ran that on regular 245/60/15s. I could hot lap it and drive it home after 4 or 5 passes. I wish I had of kept it that way at times.

Same for me in 01-02 K&N filter, some bigger tires but street tires, lock the converter & not sure of boost but around 22 It went 12.7 at 107 all day long. Just add some race gas to my 94 & hotlap it all day & every timeslip was the same. 12.71-12.72 at 107-108
KB Mag 4 chip that I still have somewhere.
Like you I wish I just left it like that somedays. If I get another one thats all I'll do.

 

[TurboTnZ06]

If I get another one thats all I'll do.

Having both right now, in the "slow" GN I just get in and drive it. It barks 1-2 shift for about half a second, quiet, effortless and comfortable to drive. A very basic recipe GN/T is quicker than most other cars on the street even today. It is just as fun to go cruise around in with the wife and kid in the backseat for ice cream in a 13 sec car than a 10 sec car.

 

["Turbo-T"]

When talking stock heads, are you meaning unported? Ported stock heads have been 9.30's. Not sure how fast unported heads have been. I have read about a few cars going high tens with an unopened stock engine. I hope to be one myself with a small Turbo. Problem is I think I'm pretty maxed out as far as my tuning skills are capable of. My time 11.39 is still far away. I'm really going to have to think about how the next .4 seconds are going to be shaved off. I know the stock cam is killing me but I'd like to run the number with it.

We will just say unported for simplicity's sake.

I've seen some running in the 10's but it almost always seems they're running at or less than 20 psi and some sort of aftermarket head.

How fast you want to go has a lot to do with fuel/boost/timing used.

Understood. I think it's cool though to be able to be in the 10's at 20 psi or less.