Hi I have a 82 Corvette with crossfire fuel injection . I was wondering if I would get the same horsepower gain if I had my air intake manifold polished and ported vs I buying.
a Renegade Intake Manifold,? Don`t want to waste good money.

 

No......and if you have the two manifolds side by side you will immediately see the reason why. The stock CFI intake port are but 2/3'rds the size of a stock Chevrolet intake port........I was told years ago that it was to promote velocity but at the expense of flow. I would not port the intake to Renegade port size for as much as a Renegade intake is worth. I would estimate about 10 hours of port time.......The other thing is that the runner entrances are rounded off nicer and the inlet is larger as well.
Our member here Buccaneer designed the intake......you might want to PM him or maybe he will pop in right here.
The intake is worth the expense and that is why Tom designed it.......to solve a huge problem with available flow.
Also, you do not want a polished intake.......a rough finish is desired to help keep the fuel suspended in the air.

Jebby

 

The short answer is NO. You can not port a stock CFI manifold to match what we have done with the Renegade. There is a ton of engineering that went into that manifold that is not readily noticeable. The rolled lip on the runners that Jebby is talking about was done for a reason, just not to look cool. That rolled lip actually rolls the charge into the runners ( flow bench tested) and the charge is accelerated on the way to the heads by some other improvements we made to the shape, angle and size changes along those runners. Not to mention the cross-sectional area changes, 20% more plenum area and more... We did allow for more porting if needed, again you can not do that with a stock manifold because of water jacket concerns.

There are a few people on this forum mainly on the C4 section (rough crowd there) that will argue that you can port a stock manifold and get good performance. OK, that is a given with what the stock ports look like and you have the time and equipment to do the job correctly, but if you want a healthy boost in performance over stock, than the Renegade is the way to go. However, we pulled our tooling from the CA company manufacturing the manifold because they were doing a horrible job with the machining. There are a few available, but I wouldn't trust them to be machined correctly.

I'm in the process of re-manufacturing like new the original tooling by the original pattern maker in Phoenix right now. They should be done soon. Then I have to go back to the original foundry here in AZ to see (beg) if I can get it done there again at a reasonable cost. If that all works out, I have the original machinist that we used in the beginning who still has all the fixtures and CNC G-code to machine the manifolds again...correctly. A lot of IF's and Maybe's there that have to happen to start this process again.

So, I guess the choice is yours. Port yours if you want or wait and see what happens with the manifold. I do have two units here, one that is brand new, but needs attention and another that my machinist already fixed and is functional. PM me if interested and I will give you my number and we can talk.

 

I would be interested if the price was right but here`s the thing I live in Newfoundland Canada how much would it cost to ship ?

 

Mmmm... Not sure about that one and customs can sometimes can be a bitch, but I bet it is around $100 US though. It 30+lbs. Oh Snap! Damn, you are out in the middle of no-where. I've been to Goose Bay several times.

 

Tell me how much you want for your intake and then maybe I can find something out about shipping.

 

Hi you never did get back to me about those two Renegade intakes that you have.

 

Oh, I was waiting for a PM that never arrived.