C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

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Old Jul 11, 2009 | 06:41 AM
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Hello

i have tuner cat and my c4 is -95 whits has cc502 cam 52mm tp, 2"00 valves 1.56 , headers, tru x-pipe, 1.6rollers, 3" exhaust, heads are done 180cc.

the questition is in whits taple you adjust rich or lean?

Jukkis
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Old Jul 11, 2009 | 01:38 PM
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There's no set formula. You need to buy some datalogging software to see what your car needs to have done. AutoXray is good stuff, as is Datamaster. Go for a 15-20 minute ride with your laptop logging data, then come back home and analyze it. Give it more gas wherever it's leaning out and vice versa, then go for another ride and see what happened. Repeat until you're satisfied, or tired.
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Old Jul 11, 2009 | 07:45 PM
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Originally Posted by StealthLT4
There's no set formula. You need to buy some datalogging software to see what your car needs to have done. AutoXray is good stuff, as is Datamaster. Go for a 15-20 minute ride with your laptop logging data, then come back home and analyze it. Give it more gas wherever it's leaning out and vice versa, then go for another ride and see what happened. Repeat until you're satisfied, or tired.
Ok i unterstand that butt whits is the tables where i do those changes?
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Old Jul 11, 2009 | 11:07 PM
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jukkis, just curious is you car an auto or manual trans? If it's a manual I might have a pretty good tune for you to try.

Also from your writing, I'm assuming your not from the US?
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Old Jul 12, 2009 | 12:40 PM
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Hello stl,

Yes im not US like yuo notise, im from Finnland!
My car is automatic!
Let me know how to tune if my car is too lean or rich in closed loop!?
Also i have 3" race cats in.

Jukkis
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Old Jul 13, 2009 | 02:05 PM
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Originally Posted by jukkis
Let me know how to tune if my car is too lean or rich in closed loop!?
First before making changes to the tuning tables you need to datalog to see if the car is rich or lean. With the engine combination your are running the stock tune may not be that far off.
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Old Jul 13, 2009 | 03:19 PM
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hello,
I have doing datalogin and there is on idle some hesitation and login i saw that left side inj time is always more than other side?
Left blm is near that 128 butt right side is 140-160 those sterm counts.
I think that difference are reason on that hesitation!
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Old Jul 13, 2009 | 03:25 PM
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There is a fix for the split BLM dilemma; has something to do with the IAC valve IIRC. I'll see if I can dig up the link...

EDIT: found it: http://www.camaroz28.com/forums/arch...p/t-23102.html
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Old Jul 13, 2009 | 04:32 PM
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It sounds like you might have a vacuum or exhaust leak on the side that is showing 140-160 blms. Also, what how does the o2 voltage look from side to side?
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Old Jul 15, 2009 | 02:22 AM
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Originally Posted by STL94LT1
It sounds like you might have a vacuum or exhaust leak on the side that is showing 140-160 blms. Also, what how does the o2 voltage look from side to side?
Ok i tryet that TB adjustment and yes it has some differense butt it not stayet there long time ( split BML) so i haveto also try change ignition too! Butt there is many taples to do this?

Jukkis

ANd thanks for any hint what you boys let me know, even writing is bad
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Old Jul 15, 2009 | 09:33 AM
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With your engine combination there is no way your split blm's are a tuning issue. You have a mechanical issue, vacuum leak, exhaust leak, o2 problem, ignition problem, ect. It would be a mistake to try to correct this problem with tuning.

Are you running a stock throttle body?
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Old Jul 16, 2009 | 12:52 AM
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Hello STL,

No im not have oem tp, it is Edelbrocs 52mm tp!
And i m did not tuning that BML only i tryet to adjust those plates whit that set nut.
there is code h41 once in while? and that drivers side running very hot if you compare it to passenger side? i have chek my exshaust not leaking. Also i change O2 sensors to one to other side. No differense!

Jukkis
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