How much boost u guys run on 93 with no knock?

[camaro75racer]

Just wondering how much boost you guys are able to run on 93oct with zero knock on our hot-airs? Just want to get an average from you guys so ill know what i should be expecting.

 

[boostmaster]

18 psi no knock, depending on the weather sometimes 20 psi.

 

[Jerryl]

18 psi no knock, depending on the weather sometimes 20 psi.

Is that 93 only or are you suplimenting with meth?
What timing is your chip?

 

[boostmaster]

Straight 93 no meth, JL low timing chip, I think 18*.

 

[UnderdogGN]

i used to only be able to run about 12-14 #'s with like a 20 degree timing chip....

 

[FlaBoy]

Right now mine peaks at about 11-12, then settles down to around 10... I could probably go higher, but I need to sort out some exhaust leaks, and maybe a little headgasket leak before i try messing around with more boost, so I'm happy where its at.

 

[camaro75racer]

Thanks guys. Im only able to get around 12psi before i register a little knock. I have noticed that my TPS does not go to the recommended voltage (im only seeing about 4.3v) would raising this help any? I currently have a huge crack in drivers side header but havent changed out for repaired header yet. Will that allow me to run more boost? Will it improve spool time? Thanks again guys

 

[Larry Smith]

Set the TPS, fix the crack, check out how much timing in the chip, and everything will be much better. Exhaust leaks kill boost. Generally speaking, a fairly aggressive chip should allow around 16lbs of boost without knock on 93 octane gas. My experience is... a otherwise stock TR running 16lbs of boost with as much timing as possible without knock, is faster than a car running 18lbs of boost with less timing. Others may disagree, but that is my experience.
Regards

 

[esinger]

Timing vs. Boost

This is a great discussion and have been wondering about timing versus boost. Larry, in regards to your statement about adjusting timing as much as possible, how do you know when you've reached the highest possible timing. I don't have a stock turbo anymore, but a TA-49, so 16lb of boost as a goal might not work for me.

Thanks

 

[Larry Smith]

esinger,
I can't answer your question concerning when you know you've reached the highest timing. Let me caution that I have zero experience with hot air cars, so take what I say as my experience only. For many years I used an old Hypertec stage 3 chip. I believe it had 23 degrees timing. Maximum boost was 15-16 lbs on pump 93 without detonation. I took some serious kidding for my old fashioned ways and finally decided to go with a higher boost Thrasher chip with less timing. The car slowed down by 3 tenths. It also seemed to take longer to reach it's shift points. I believe this was because the car was building speed slower. I switched back and forth many times between chips and had the same results every time. Obviously there comes a point when boost is going to make more power than timing, but when your under 18 lbs. I believe the opposite is true.
I would think that your TA-49 would allow you to run a little more timing, because your moving cooler air than the stock turbo. But you need to make sure you have the fuel to support it.
Clear as mud?
Regards,Larry

 

[SLOW_85]

I usually run low timing chips,high boost.
Course I inject methanol.
The hot-airs are more affected by weather conditions.
Cooler air, more boost. Warmer, humid air less boost.
When we had 93 octane here, I ran 17-18#'s without knock.
Now all we have is crappy 91 octane.

 

[fbodlovr]

I hate to hijack this thread, which im not trying to do, but what times are you guys running with hot airs when you are pushing close to 20psi?

 

[SLOW_85]

I haven't run at the track since prolly 2002. Was down in the 13's on 93 octane and meth injection,limited traction.
Ran some Cobra's dead even and out run a few on the street. :biggrin:
Currently have the car apart, adding a bunch of new stuff.

 

[esinger]

Well can't say much yet about 20lbs of boost, but I'll soon know more. As Larry pointed out fuel is key and at this moment I'm running 30lb injectors and I can't turn up the boost until I get the 009s in. I already have the chip and now waiting for the 009s to arrive. I'm not looking forward to taking all the hardware off just to put in the injectors, but as you know what they say about pain and gain.