pump gas tune

xcessiv6

Boom Tube
I won 2 pulls on a dyno I don't drag race anymore and drive the car I can run 20lbs of boost on 92 octane with 17 degree timing. I don't use anything else I never see knock is their much left in the tune.
Combo
231 stock bottom end billet mains and studs
P &P heads all the good parts 1.65 roller rockers
210/205 cam GSCA
T64 turbo
Cas front mount
60# injectors
3" MAF and Translator
70MM thottle body and RJC powerplate
Turbotweek chip
My race setup was the same with 42.5lb injectors and on race gas at 24lbs of boost went 11.60 with a car weight with driver around 3900lbs on DR,
 

TurboDave

RIP DAVE
Staff member
TurboBuick.Com Supporter!
I won 2 pulls on a dyno I don't drag race anymore and drive the car I can run 20lbs of boost on 92 octane with 17 degree timing. I don't use anything else I never see knock is their much left in the tune.
Combo
231 stock bottom end billet mains and studs
P &P heads all the good parts 1.65 roller rockers
210/205 cam GSCA
T64 turbo
Cas front mount
60# injectors
3" MAF and Translator
70MM thottle body and RJC powerplate
Turbotweek chip
My race setup was the same with 42.5lb injectors and on race gas at 24lbs of boost went 11.60 with a car weight with driver around 3900lbs on DR,


You're probably pretty close to your tune's limit. I also run a similar setup with some differences. I run the CAS front mount, but with a PTE44, and MSD50's. Otherwise the engine its self is bone stock.

I'm able to run the following on 93 octane only:
21# of boost in 1st and 2nd with 21° of timing
20# of boost in 2nd and 3rd with 18° of timing

I'm pretty sure I'm at my limit and wouldn't want to try and go any further
On rare occassions I will see a little trickle of timing retard of something less than 1°
 

xcessiv6

Boom Tube
Thanks dave i know i'm close i can get unleaded 100 octane i think i will try that and turn it up a couple pounds. Thanks for the help
 

TurboTnZ06

Go on red!
I ran 20-21* timing last night on pump gas and 17 psi and only ran 103mph in the quarter in a full weight GN (baby seat in the back, spare in the trunk).

I see it now, Missing ? mark. I like good grammar, Nice buick Xcessiv.

Dude, the grammar police are not amused with your grammar about good grammar :eek:

"I see it now. You were missing a question mark. I like it when people use correct grammar. Xcessiv, you have a nice Buick." :biggrin:
 

murphster

Well-Known Member
Cool to see some info on pump gas tunes. I've been playing around lately on pump gas (no alky) and reading up on what tunes people have used. Seems to be most are runing from 17 to 20 degrees of timing with those running less timing being able to make more boost. Some people have said that even though you can run more boost with the timing pulled down to 17 degrees, that it isn't necessarily making more power.

Last week in some hot weather on pump gas, I was able to run 19lbs of boost with 19/18 timing running almost 111mph in the 1/4 on street tires with major peddling in the beginning of the run. I upped the boost to 20lbs and pulled out only half a degree timing but let out because I started to get a little knock up top. My ET was quicker though and I upped my 1/8 mph from 87mph to 90mph and knocked almost two tenths off the 1/8 ET. If I lower the timing down to 18/17 I don't think I'll get any knock at 20lbs boost and will run faster than 19lbs boost at 19/18 timing. I think I can get 112-113mph out of it. On sticky tires not peddling it, maybe 115mph.

I think the heat was hurting power too, as it was almost 90 degrees out and muggy. Curious if I will got knock in say 70-80 degree weather at the same boost. The inlets temps going into the MAF were also very high as I just had a cone filter under the hood. I think the IAT temps were at 150 degrees or so. I put my big mouth cold air kit on and the inlet temps are now close to ambient air temp. On alky I didn't notice any difference in power as it seemed to neutralize any advantage the lower inlet temps could make. I'm curious if there will be advantage with the lower inlet temps when I'm not running alky. I know a lot of people say the airflow restriction form a cold air kit hurts the potential, but I also switched from a 3" MAF pipe to a 3.5" MAF pipe with the 4" cold air kit so I doubt I'm hurting any airflow.

Anyway, I'd also like to hear more input from others running pump gas only for ideas. Any experience from running in hot weather to cooler weather and the effects would be appreciated too. I saw a lot of info on pump gas tunes, but not many where people were racing though. I'm shooting for high 11s on pump gas and street tires. I've already run 11.8@118 on street tires and 11s on pump gas and sticky tires would be no problem. Doing it on both is a challenge though.
 
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