233/239 Cam, How do I tune for drivability ??

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May 28, 2005 | 10:20 AM

racecar

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233/239 Cam, How do I tune for drivability ??

C5 6 speed with a new LS6 motor. 11.5:1 CNC heads, LS6 intake, TSP 233/239 .600 cam. MAF de-screened, headers no CATS. I only have about 20 minutes on the motor, it stumbles when it starts, idle is OK, but not real drivable. It just seems real sluggish at low throttal, no real quick throttal response. I put my foot to the floor and it definately responds there. Plenty of potential when I get around to tuning for WOT.
I set the VE tables down at 400,800 etc, What else do I need to do to get some low end response? At low rpm it feels like it has throttal lag, with this cam and heads, it should be really responsive. I am a rookie at tuning, where should I start working? MAF recalibrate ??
Why are my LTFT Avg on 0 ??
Thanks for any ideas!!

May 28, 2005 | 12:35 PM

Cal

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Big cams can make the motor lazy at low rpm. Usually you compensate for that with gears to get the rpm up quickly to where they like to run. My TSP 235/240 is surprisingly good down low, but it runs rough below 2000 rpm. I also have 4.11 rear end gears.

May 28, 2005 | 02:59 PM

racecar

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So the solution is just keep the revs up??? It is never going to be quick from 1500-3000?

May 28, 2005 | 03:33 PM

luv2spd

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You probably won't gain over the stock cam till around 2500 or so.

May 28, 2005 | 05:33 PM

racecar

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I don't really expect it to have power at 2000, just driveable, so with the clutch in, when you push on the gas pedal the engine will rev immediately. Now there is a lag. You push and it goes blaaaaaaa then it revs. The stock LS1 motor had a lot more throttal response down low. I just expected a lot of response from a race motor. I need to change the lifters before any WOT runs. Comp R lifters are just hammering worse than solids. I have tried adjusting 2 times. Maybe I have a lifter that is bad??

May 28, 2005 | 05:44 PM

Rick@Synergy

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Its called Timing. More timing. RPMs have nothing to do with it.

May 28, 2005 | 06:26 PM

WS6FirebirdTA00

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u can add more timing but you really have to get your idle tables set right on. im reworking mine and every tune the car gets better and better. if i touch the gas the rpms shoot up very nice and i havent touched the ve yet. if u need help with this pm me and i can show you what i am doing right now