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New track times with 11 pound pulley. SLOWER!!!

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Old 09-06-2003 | 10:37 PM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

After taking a nap, I don't think that you exhaust is the problem either. I wish I could help more but I have given it my all.
Old 09-07-2003 | 12:54 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Went and logged 3 runs with the g-tech--15.2 15.3, and 15.2. The 15.3 was when I closed the cutouts.
During those 3 runs,
--- A/F was at a constant 11.4-1 for the entire run.
--- 0 KR entire runs.
--- MAF maxing at 48 lb/min tonight!
--- timing 1st gear- 22-15 degrees 3500-5700rpm
--- timing 2nd gear- 20-12 degrees 4000-5800rpm
--- timing 3rd gear- 16-11 degrees 4200-4480rpm

To me, these numbers don't seem too far off. Do you guys think there is a whole second in changing timing and leaning A/F a little
Old 09-07-2003 | 12:58 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Also no tq management pulling timing on the shifts or the launch. Pretty sure I deleted it all.
Old 09-07-2003 | 01:35 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Went and logged 3 runs with the g-tech--15.2 15.3, and 15.2. The 15.3 was when I closed the cutouts.
During those 3 runs,
--- A/F was at a constant 11.4-1 for the entire run.
--- 0 KR entire runs.
--- MAF maxing at 48 lb/min tonight!
--- timing 1st gear- 22-15 degrees 3500-5700rpm
--- timing 2nd gear- 20-12 degrees 4000-5800rpm
--- timing 3rd gear- 16-11 degrees 4200-4480rpm

To me, these numbers don't seem too far off. Do you guys think there is a whole second in changing timing and leaning A/F a little
How come your timing drops off in the later gears?

Another thing I thought of was... would you need more timing at lower RPMs as there is no boost there? I can see pulling timing from the upper RPMs but not until boost comes on.

Like you lose timing as RPMs rise as you boost rises with RPMs unlike a Roots/Twin Screw as where the boost is almost instantaneous.

Is there a point where the MAF gets pegged out?

I hope I am making sense here with my reasoning...it is 1.30am or something so time for again before I ramble on
Old 09-07-2003 | 02:59 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

WTF? those numbers look fine to me, sure you will want ot tweek them to get the most out of it but they are not far off from where they will end up.

I am stumped, i guess it is time to look at some basic stuff.

you dont have a 4.8 do you?
how does it run, like idle and cruise, dont have any major vacume/boost leaks in your intake?
prety sure a miss would throw a code right away, you didn't disable the missfire stuff in edit did ya?
how close are your cut outs to yout 02's? the factory ones and the WB one?

hmmm.. last thing i can think of right now, maybe what i said first off is wrong, with an intercooler maybe those numbers are way short of where they should be, i just can't see it killing your ET that much but who knows. try pushing that a/f up to 12-1 and then adding timing a little at a time till you see KR or hear pinging then pull a couple back out. with the intercooler who knows you might be able to lean it out alot and run 20deg of timing.

Old 09-07-2003 | 04:21 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Another thing you might check. Look for a film of rubber on the blower it self. If your belt is sliping even a little bit it could cause you to loose performance. Your boost gauge will still show full boost reguardless. So make sure you dont referance from the guage. You will be amazed on how much volume air you can loose weather it is a leak or a sliping belt and still show full boost.

On my old motor i went from a 13lb. to a 16lb. pully and it made it about two cars slower just because it was sliping so bad.
Old 09-07-2003 | 08:18 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Giver it some Timing !!!
I could get away with 4-6 degrees more than you
timing is free horsepower and you'll for sure feel 4-6 degrees
Where did you buy your pulley from ati?or reichard racing one ?
I'm willing to bet that you are slipping on that 3.6" pulley
what i would also check is all the intercoler piping Clamp give it a once over and make sure all the band Clamps are tight
Things to do Add some timing it'll help you all over
after you add the timing see where you are with the fuel and see if you can lean it out some
Just listen to your engine for pinging because the knock sensors will never show anything on the 2002 it'll have to throw a rod for it to say there is KR
Do you still have the stock intake in to the throttle Body ?

jim
Old 09-07-2003 | 10:09 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Another thing you might check. Look for a film of rubber on the blower it self. If your belt is sliping even a little bit it could cause you to loose performance. Your boost gauge will still show full boost reguardless. So make sure you dont referance from the guage. You will be amazed on how much volume air you can loose weather it is a leak or a sliping belt and still show full boost.
Just what I was going to suggest! I had this problem on with my Suburban. The truck felt gppd with a smaller pulley but it was slipping so bad there was belt powder all over the engine compartment. The truck lost about 20-25hp instead of gaining about 30. I'm running a Goodyear belt now and it's good now. The extra boost and cool temps last night would get the 22s spiining from a 5MPH roll. Something it didn't do before

Old 09-07-2003 | 10:29 AM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Hit Man X- I don't know why timing drops off in later gears. I was thinking that was normal because of increased load?

Parish- got a 5.3, runs perfect, no leaks that I know of.
MY cutouts are about 3 feet downstream of my rear 02's. I have the wideband in one of the rear holes.
408- Theres no rubber dust on or around the blower at all. Whats the best way to check for a boost leak?
Gmc ski- I'll try more timing, how much did you run? Did you run the same amount in all gears, or did it drop off like mine? Which tables did you adjust to add timing? The pulley's a Reichard Racing with a gatorback belt.
Thats sucks about the knock sensors. Sometimes I get KR in lower rpm's just cruising. So I have seen them work.
Still have the stock intake. I want one like yours, but that means i need electric fans too$$. There just isn't room for anything without e-fans.
The thing that has me stumped is 8 lb/min more MAF flow and 0 gain at the wheels. Could the parasitic drag of the charger be using up my gained power? Maybe the charger is making enough airflow for 5 more psi, and only 2 psi are getting through the intercooler. Guess I'll have to measure boost drop across the intercooler.

Any other ideas? Thanks for all the replies.
Old 09-07-2003 | 12:12 PM
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Default Re: New track times with 11 pound pulley. SLOWER!!!

Hit Man X- I don't know why timing drops off in later gears. I was thinking that was normal because of increased load?

Any other ideas? Thanks for all the replies.
Is there a pressure limit that the ATI's intercooler can flow? I remember someone on FSC.com saying something about a 9psi limit for some reason.

But wouldn't you run the same load in all gears at the same boost/rpm levels?


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