Ok, I dyno'd my car this past weekend and was disappointed. I have a 396 stroker, and it only put down 340 to the wheels. Someone told me today that if I switch from Mac midlengths to a long tube header, I'd probably see 20rwhp gain. Is that honestly true? I thought I read a while back that it ended up being very similar between the two. Anyone have hard data? Thanks.
Dan

 

You would see gains, but I wouldn't think 20 ponys. Just enjoy the ground clearance of a mid length.

 

Only 340rwhp out of a 396, id find out why it isnt running right before i started doing anything else.

 

Definitely. There are guys making that much out of 350's...you've got a frickin' 396 stroker for crying out loud.

 

definately something wrong :/

 

I agree something is wrong, but I didn't know it until we dyno'd. So now the hunt begins.....

 

You would probably gain more low rpm power, maybe not 20. The headers are more than likely not the problem, maybe tuning not right?

 

Where does the power peak at? Its hard to diagnose if there is a problem or what kind of problem it may be with only knowing the peak number. If you can post a graph, Im sure we can help more. I'd say your cam is fairly small for a 396 tho.