jeremy341a

iTrader: (2)

I am planning on using my Z28 to bracket race. I want to know that if I pull a little timing will it hurt anthing. I know it will not be as quick but I am worried about making the car more consistent? Can I use the predator for this? Any recommendations on how much to pull, 10% maybe? Just kicking around some ideas, haven't decided yet if I'm going to got with the predator or a mail order tune? I would probably do the mail order but I have no easy,cheap way to do the crank relearn when I want to swap back and forth.

12secSS

iTrader: (30)

If you are going to be serious about tuning for bracket racing, I would suggest you invest into a tuning program of your own. This way you can have multiple tunes ready to go if you need to either slow the car down or give it back more of it's potential. Pulling timing, depending how much, willnot really affect your vehicle, but it will drop power. Depending on your setup, it could be around 15hp for 2 degrees of timing.

I would tune it for the most potential really, unless you are exceeding an ET class limit, like a sportmans class or the .90 classes (10.90, 9.90, 8.90) where they need to slow them down (ET wise). Bracket racing is more of how consitent the driver is, not really the vehicle. It doesn't matter how consistent you make a car, if the driver can't be consistent it won't matter.

jeremy341a

iTrader: (2)

I understand what you are saying but I want to pull the timing so that the car is never pulling it at random times going down the track. I have drag racing experience. I finished second in superpro points at Gateway this year, and have raced a street car in the past. So I'm hoping I can do my job. Just trying to make sure it doesn't throw me a crazy number. This is basically a stock car, except for lid and a few other things. Just going to race it in the street class and the dragster in the superpro class.

foff667

iTrader: (2)

you can do that & still run quicker times with tuning software

I'd rather have a faster car knowing if I get on the brakes & have to get back into it I've got more then the guy next to me. I also don't like having to catch up to people if at all possible.

jimmyblue

iTrader: (11)

You can stop it pulling timing, but running contant timing
against changing engine / air temps does not mean that
(necessarily) you will be more consistent. Ideally GM would
have made IAT / ECT adders that kept performance (or
just lack-of-ping) constant. But that isn't what we got.

My opinion is that if you want consistency, address the
things that jack your intake air temps and coolant temps
around in the first place - cold air / air source control
schemes, fan settings / better radiator and the like. The
problem is not the PCM pulling timing, but why.

I have an old model Predator and it's no way adequate
for that. Dunno about the new, improved, too bad for
you early adopter chumps, model. Nor how present
pricing compares to full-capability tools. But if you're
already in this "burn money" hobby I think the capability
probably matters more to you than half priced for half
assed.

jeremy341a

iTrader: (2)

Good points. I also like your "burn money" comment.

HumpinSS

iTrader: (1)

Also running to little timing tends to over heat the engine, loss of power and nice black piston tops...

SSpdDmon

iTrader: (10)

Usually when you race, you get a few passes in before eliminations. I'd leave the timing stock (assuming you have just bolt-ons) and watch the Predator on the way down the track. If it's a hot day and you see knock retard, back off the timing a little to make it go away before you run your bracket. But, I woulnd't pull excessive timing to prevent possible knock retard that may never happen. These cars are fairly consistent with bolt-ons, a set of sticky tires and a good driver. Just know that as the air gets cooler, your times will drop. Experience at the track is what you should use to determine just how much faster you'll run in the cool, dense air - not guessing "x" amount of timing pulled is needed to avoid potential knock retard. But, that's JMO...

jeremy341a

iTrader: (2)

I just want to pull about two degrees so that as "wait4me" told me it wouldn't be on the edge. The problems is my old car would not always be predictable, sometimes it would slow down a tenth, and then pick it right back up for no apparant reason(traction, weather). I always suspected it was getting some knock and pulling a little timing. However I suspect it may have also been the torque mangement.

foff667

iTrader: (2)

These are all things you'd be well served by buying tuning software of your own...hptuners offers up to 1hr 30mins of standalone datalogging meaning you could literally log each & every one of your runs in order & download them when you get home to analize exactly what was going on...TM, knock retard, burst knock, iat, ect adders, etc. Then make adjustments...or make them at the track

jeremy341a

iTrader: (2)

that sounds interesting, but I feel like Cole Trickle in "days of thunder" when he tells Harry that he has no clue what he is talking about.

I only understand about half of what your saying.
I feel like for as little as I want it for that hptuners would be overkill. I only wnat the tranny features and maybe pull a little timing and such. I can get a predator for 250 so price is a factor also.
thanks for all the help