Ok here it is everyone I need help. My friend recently had his 96 lt1 rebuilt into a 383 expecting to have a Hugh horse power increase. Instead the car is SLOW. I mean no get up and go at all. At idle the car sounds great but when you get into the throttle the car stumbles and makes loud back firing noises that sound like they are coming from the heads not the exhaust. We have checked fuel pressure, changed plugs, and changed wires, ran it with and with out the msd 6al, replaced the optispark system and treated the fuel. What do you think is the problem? Could it be a bent push rod or a lifter? I checked the valve springs and they look ok to me.

 

crossed wire

 

Did he get it tuned.
How about ported heads?

 

crossed wire or poorly adjusted roller rockers. maybe even off a tooth.

 

Well we checked the push rods tonight and they dont appear to be bent. we will check the plug wires soon.

 

crossed wire or poorly adjusted roller rockers. maybe even off a tooth.
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1996 Formula Chamaleon m6
383 LT1 LE3 http://www.cardomain.com/memberpage/430619

Engine in the machine shop, soon to be done.


what do you mean by off a tooth???

 

it has reprogrammed by pcm for less after the rebuild. I guess the car ran good for a day or so then lost power.

 

In that case it is most likely a burnt wire or 2.... Ask me how i know. lol

 

How do you know? haha jk

Mark

 

thanks for the advice everyone i will check it out to see if any of the wires are crossed or damaged.