Yes, the exhaust is raised .600" like most others.

Chris

The only aluminum heads I have heard that are not is the Eldebrock.I don't think they have very good port velocity.

What about the pro 1"s??

Strip Poker 388
AFR told me the exhaust is raised .375".

Does the 741 cam help the performance of a stock HP 500 (carb) ?

no disrespect to anyone but no way now how is a 500hp carb motor with a cam and 315cc cnc ported heads going to make 600hp at 5400-5500rpms. sorry it is just not going to happen on pump gas. save your cash cmi's are not going to do anything beter than your gill's. in a perfect world with afr heads, bumped up timing a little, bumped up comp. a little and good cam you might gain 100hp. a stock 500hp is like 465hp.

While we are on the subject, on a carb HP 500 what rpm's do you prop for to obtain max top end speed?

4800-5200 - labbed 26 4 blade on a 288 sunsation ,

So on a side by side installation the stock cmi headers should not touch.

I wonder if there is enough slack in the hose to accept the .375 higher exhaust port to line up with the tail pipes???


What do yall think??????


Rob

Hey Jeff , Drew here, You can always do what I did Blow A Motor and step upi to 540,s... Runnong a strong 80 plus right now !!!

if you use the CMI with the flex flairs the tail pipe has some adjustability. If you buy a used set even if they are the cool collar design make sure the tail pipe connection is the flex flair design the one they make for Mercury are not.