i got a 68 camaro that has a 305tpi 700r4 in it, and a set of summit hedders and 23" glass pacs, stock chip and computer and no smog. what i want to do is to get that muscle car rumble when im setting at the red light or when it is at idle. i got poly motor mounts and what to feel the motor shake like my dads truck. the map senser limits me right? any help is good help and thanks for it all the biggests is what i want http://www.geocities.com/claycitydude/68

 

help

 

Yes, if you have a map sensor, it senses the manifold pressure and changing cams to achieve the lopey idle you want will also require a PROM change for the computer.

 

if you are looking for a choppy idle, just order a cam with LSA of 110, your gonna need to reprogram the computer for the cam, and dont expect it to make optimal power with TPI and a LSA of 110, but it will have that muscle car chop

 

do i reprogram the comuter or buy a chip and what chip do i need or how do i reprogram the computer what is LSA

 

I'm by far no cam genius, but I have to question that statement. Do you remember the Super Profile L98 cam from TPIS. The one that was around 490-510 lift with about a 207-212 duration. It had a 108 LSA and from what I had read, it ran like a bat out of hell on a stock engine. That of course means no prom changes. However, I am curious as how much it loped.

 

LSA is lobe separation angle basically it's one factor that determines the overlap between the intake and exhaust. A lower separation is a greater overlap which is essentially what gives you that lopey idle.

I could be wrong but I'd say any cam change, especially going with say a 108 LSA would really require chip work. In which case I cant stress enough the need to burn your own chips. Go to the DIY-PROM board and start reading up and check out the prom burning intro article https://www.thirdgen.org/newdesign/tech/promintro.shtml

By the way nice little project you got there, good luck with the rust I know exactly where your coming from. Got a 69 Firebird convertible in a bit rougher shape, but it's all there. Would have given up on it long ago if it wasn't a convertible

 

i dont see how any cam with a LSA of 108 could run on the stock chip. that would have to throw the computer for a loop. maybe that was intake centerline or something.

 

why cant this be easy thanks for the help when does the cam mess with the map at low rpm or high

 

The LSA on it was 108. I even posted a thread about solely it and willie (supercharged 305 camaro) said he knew someone or wondered why TPIS cams made cars run so fast for what they were. I'm not saying running on 108 LSA on the stock chip is perfected, just saying I believe it's possible.

 

ok im to the point where i want to order a cam which one is it guys. the muscle car sound and lopyyness is what i want. it has hedders now. http://www.geocities.com/claycitydude/68 here it is if you want to look

 

Those arent headers...