85 Vette with a 406
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3rd Gear
Joined: Dec 2009
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From: Elkview WV
85 Vette with a 406
I have put a 406 in my Vette it has close to 500hp...It has 11-5 comp AFR heads after market intake...I'm having problem with it running rough at low RPM...I'm being told that I need to have the computer reprogramed is this true
Race Director
Joined: Feb 2004
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Le Mans Master
Joined: Aug 2007
Posts: 8,735
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From: WV
Hello fellow West Virginian,
If you have a stock chip and put that engine in your car, your lucky if its running at all . Also be careful because if your running to lean or to rich you can damage your engine. If you spent the big bucks on a new engine and want to get the most out of it, a custom tune is good , a Dyno tune would be better.
..WW
If you have a stock chip and put that engine in your car, your lucky if its running at all . Also be careful because if your running to lean or to rich you can damage your engine. If you spent the big bucks on a new engine and want to get the most out of it, a custom tune is good , a Dyno tune would be better.
..WW
Thread Starter
3rd Gear
Joined: Dec 2009
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From: Elkview WV
It has a stage three chip in it and bigger injectors too...Just don't think it is smart enough to run it...Just wondering if anyone else had to do the same thing hate to spend that much money if it is not going to fix my problem.
Race Director
Joined: Apr 2003
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From: moraga ca
If you don't get a custom tune, you might have to have your local engine man rebuild the thing soon. I have an accel dfi running my 406 and am tinkering with the program every week or two.
Pro
Joined: May 2002
Posts: 635
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From: New Jersey
The camshaft will also dictate how the car idle with the tune. How much duration and lobe separation and C/L. I also have a Accel DFI that I pickup with a Superam. I was changing the program every couple of days. I ended up putting the stock ECM back in and having PCMforless burn a chip for me.
Randy
Randy
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Race Director
Joined: Feb 2004
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You have to decide what you wish, before anyone can even guess at cost.
How much power?
Hp or torque?
Pump gas? Or race fuel?
Street car or race car?
If race car, what type? What Class?
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Ditto on Mick. Those generic Stge 1, 2 3 chips arent going to do the job. Get him on the phone he really knows what the heck hes doing.
Instructor
Joined: Nov 2005
Posts: 161
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From: Pittsburgh Penna.
Don't jump so quickly to a custom tune. The 85's ECM is far less sophisticated than the later vettes. The MAF generally allows thhe ECM to be far more forging of changes and the chip for this model really doesn't permit "tuning" On my 85 I switched to aluminum heads from an 86 which bumped up the compression, added headers, roller rockers, cam and eliminated the air pump and EGR all without needing a chip or throwing a code. My two cents is to make sure everything is right with the engine before you assume you need a "custom tune"
Race Director
Joined: Apr 2003
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From: moraga ca
Don't jump so quickly to a custom tune. The 85's ECM is far less sophisticated than the later vettes. The MAF generally allows thhe ECM to be far more forging of changes and the chip for this model really doesn't permit "tuning" On my 85 I switched to aluminum heads from an 86 which bumped up the compression, added headers, roller rockers, cam and eliminated the air pump and EGR all without needing a chip or throwing a code. My two cents is to make sure everything is right with the engine before you assume you need a "custom tune"
Intermediate
Joined: Jan 2010
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Melting Slicks
Joined: Sep 2000
Posts: 3,099
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From: PITTSBURGH PA
Cruise-In IV Veteran
Cruise-In V Veteran
stock 85 computer
stock maf
stock dana 44 with the stock 307 gear in it to boot
700r4 transmision
But i think it was only getting like 23 mpg
