1/4 mile times on pump gas?

[darkred87T]

Hi, I recently upgraded to Champion P&P heads and 206/206 roller cam. I had the car at the track last weekend and ran an 11.8@112MPH on pump gas and alky. The alky PAC knob was only turned 1/4 past off. My EGT's were low 1500's, WBAF was high 10:1/low11:1 and boost was 22-23 lbs.

I was driving around tonight and recorded a quick 0-60 run with 93 and no alky. My EGT was mid-high 1500's (a little higher), NBAF was high 700-low 800's and WBAF was high11:1/low 12:1.

My question is, is this normal? It looks like I'm running a pretty agressive tune for just 93 but it doesn't seem to be causing any (real) knock. Should I try making a pass with only 93? I can't get any more boost out my turbo so turning up the boost isn't an option.

I have both runs recorded on Power Logger. If anyonme wants to take a look, I can post the link.
Thanks,
Mike

 

[carloslara]

witch turbo unit you have?

 

[darkred87T]

It's a Precision GT3255. I have it maxed out running 22-23 lbs. with no boost control and the waste gate wired shut.

I took it to the track again last night. I couldn't get it to hook up all night but I ran consistant 113MPH every time. With alky my WBAF is 10:1. I kept turning it down but I didn't have the guts to shut it off all together. I think I'm going to upgrade to a bigger turbo.

 

[carloslara]

base in what i've seen and readed, you should try with 20 lbs pounds of boost and increase your octane fuel to 100-105. obviously i guess you have the chip from poston, to increase the timing grade,tps forward, to get advantage for it. i'm seen people doing the same time as you with less pound of turbo. (18-20), sometimes , some turbo get stall if you push so hard.

already have a grand national 1987, i'm preparing the engine, with the stock turbo (16-17 psi), after i finish the mechanic i need to make a paint job. but i will try with LPG INJECTION SYSTEM, rated 105 octane.

Tartarini Auto Industries - Gas Equipments

 

[QUIP'6']

It's a Precision GT3255. I have it maxed out running 22-23 lbs. with no boost control and the waste gate wired shut.

I took it to the track again last night. I couldn't get it to hook up all night but I ran consistant 113MPH every time. With alky my WBAF is 10:1. I kept turning it down but I didn't have the guts to shut it off all together. I think I'm going to upgrade to a bigger turbo.

i see with that little bit of alky is keeping the a/f's and egt's down which is doing its job 22/23 psi on pump gas is at the ragged edge with that 12.1 a/f if you cant get more boost then just up the timing. what chip are you using. also do you have a heavy duty accuator. i think your car is tunes very well to get away with that amount of boost.

 

[darkred87T]

base in what i've seen and readed, you should try with 20 lbs pounds of boost and increase your octane fuel to 100-105. obviously i guess you have the chip from poston, to increase the timing grade,tps forward, to get advantage for it. i'm seen people doing the same time as you with less pound of turbo. (18-20), sometimes , some turbo get stall if you push so hard.

already have a grand national 1987, i'm preparing the engine, with the stock turbo (16-17 psi), after i finish the mechanic i need to make a paint job. but i will try with LPG INJECTION SYSTEM, rated 105 octane.

Tartarini Auto Industries - Gas Equipments

I don't think I have a Poston chip unless they make the Extender Pro. I'm not sure if I can run any other chip with my Translator-pro however I can move timing with the T-Pro. I have it set at 25 degrees WOT for now.

When I was at the track this past Friday on my first run I spun out of the hole and it pulled 10 degrees of timing. I went back and looked at my log and my EGT was in the 1600's when it pulled the timing.

I'm guessing watching the EGT is my best way to tune for now. Hot exhaust means detonation is a sure thing right? The safety zone seems to be about mid 1500's as it won't pull any timing before that. My knock gauge/sensor is useless as it goes into the red under ANY acceleration, even with only 2lbs. of boost. God knows, it'll stay in the green when I have real knock so I don't even look at it. But that's a different issue.

Bottom line is, I need a bigger turbo. My GT3255 is maxed out and my WOT timing is already at 25 degrees.

Anyhow, I think I finally found the thresh hold with my tune. Without alcohol, my WOT AF is 12.1:1 which I think is a little lean but with just a little bit of alky, it's right down into the high 10'-low11:1 AF. My best time is 11.8 but my best MPH so far is 113.6.

 

[carloslara]

how your AFR is at WOT? is very important that the air mixture not to be too much rich or lean.

I don't think I have a Poston chip unless they make the Extender Pro. I'm not sure if I can run any other chip with my Translator-pro however I can move timing with the T-Pro. I have it set at 25 degrees WOT for now.

When I was at the track this past Friday on my first run I spun out of the hole and it pulled 10 degrees of timing. I went back and looked at my log and my EGT was in the 1600's when it pulled the timing.

I'm guessing watching the EGT is my best way to tune for now. Hot exhaust means detonation is a sure thing right? The safety zone seems to be about mid 1500's as it won't pull any timing before that. My knock gauge/sensor is useless as it goes into the red under ANY acceleration, even with only 2lbs. of boost. God knows, it'll stay in the green when I have real knock so I don't even look at it. But that's a different issue.

Bottom line is, I need a bigger turbo. My GT3255 is maxed out and my WOT timing is already at 25 degrees.

Anyhow, I think I finally found the thresh hold with my tune. Without alcohol, my WOT AF is 12.1:1 which I think is a little lean but with just a little bit of alky, it's right down into the high 10'-low11:1 AF. My best time is 11.8 but my best MPH so far is 113.6.

 

[darkred87T]

Anyhow, I think I finally found the thresh hold with my tune. Without alcohol, my WOT AF is 12.1:1 which I think is a little lean but with just a little bit of alky, it's right down into the high 10'-low11:1 AF. My best time is 11.8 but my best MPH so far is 113.6.

WOT with Alky is high 10:1/low11:1.

 

[carloslara]

taking in mind your setup, i guess you should try to lean a little bit the mixture, because i found little rich. in two books wrote by Steven Dove, regarding specialist to the buick grand national, he mention that when you mod the engine, piston, heads, headers, exhaust, bigger intercooler, throttle body, ect. the optimum AFR at WOT is very close to 12:1 -11.8:1.

by my own experience tunning engine on Sequential system LPG, in TURBO engines, like 2J of TOYOTA SUPRA, i get awesome result working in 12.0:1 in WOT with 14psi of boost.


i really like to share my experience, specially with a GN owner.

WOT with Alky is high 10:1/low11:1.

 

[darkred87T]

Thanks. Alky seems to bring the AFR right down. I can probably get away with high 11's low 12's. I'll try and lean it out a little more to see what happens. I think I'm done spending money on the car for now so a turbo isn't gonna be in my near future unless I can find a screaming deal on a used one.

 

[carloslara]

good, as far i finish with my restoiration of the vehicle, and test with propane, i will let you know my results. about the turbo i hear about the TEC66 is the biggest and one of the best choice for this engine.

by the meantime i'll keep the stock turbo until i reach their limits.

my msn is muchilus@hotmail.com


Regards,

Thanks. Alky seems to bring the AFR right down. I can probably get away with high 11's low 12's. I'll try and lean it out a little more to see what happens. I think I'm done spending money on the car for now so a turbo isn't gonna be in my near future unless I can find a screaming deal on a used one.

 

[TTA850]

the optimum AFR at WOT is very close to 12:1 -11.8:1

I've also had good results targeting an AFR between 11.6-11.8 running 93 octane without alky or water injection. I keep the boost at 18-19psi with a P-trim 70mm turbo and timing starts at 21* and scales back to 18* as it goes down track, best time 11.06 @ 120mph, 3510lbs raceweight.

Good luck tuning, just take small steps and get out of it if things dont seem right

 

[carloslara]

hey nice track record, i'm planning to reach that average with propane injection system. i'll let you know the results.

I've also had good results targeting an AFR between 11.6-11.8 running 93 octane without alky or water injection. I keep the boost at 18-19psi with a P-trim 70mm turbo and timing starts at 21* and scales back to 18* as it goes down track, best time 11.06 @ 120mph, 3510lbs raceweight.

Good luck tuning, just take small steps and get out of it if things dont seem right

 

[ITSAV6]

Need Boost made a 11.77 pass on pump 93 and no alky. I went 12.15 on 93 and no alky at 17psi.

 

[carloslara]

nice bro,! what a beuty engine cabin!.

that MAF sensor is not the stock one? which type is it?

i see with that little bit of alky is keeping the a/f's and egt's down which is doing its job 22/23 psi on pump gas is at the ragged edge with that 12.1 a/f if you cant get more boost then just up the timing. what chip are you using. also do you have a heavy duty accuator. i think your car is tunes very well to get away with that amount of boost.