[kensblue65fb]

Looking to upgrade with an Edelbrock manifold. Recently installed an Edelbrock carb #1404 ( 500 CFM). engine is a basically stock 302 with the exception of tri-y headers. Should I use a carb spacer with a performer, or performer RPM manifold. What have you done?? If I use a spacer should I use the one without the PCV port.

 

[Huskinhano]

Stick with the Edelbrock Performer 289. Anything more, and you'll lose that important low end torque.

 

[camachinist]

Also consider a vintage Cobra or Edelbrock F4B.....but a Performer will work fine.

I made a 1/2" phenolic spacer with a PCV bung for the Cobra manifold on my D-coder...I prefer PCV and having it spread amongst all the runners from a central location like a spacer. Plumbing it to the carb baseplate, if such a port exists, is fine too. My 4100 didn't have one.

For me, on a stock engine, the main reasons for having a spacer is to facilitate PCV hookup and to mitigate heat-soaking the carb, due to the faster heat transfer of the aluminum intake. Cool fuel is a good thing (relatively speaking *G*)...that's why you may have seen buckets of ice (cool cans) on race car fuel systems in the past (I had one on my street racer; filled it up with dry ice every weekend *G*)

Figure about 10-12 hp from the manifold change; maybe a bit more, depending on your compression ratio and efficiency of the exhaust beyond the tri-y's...

Good luck!

 

[CAponyboy]

Port match the intake to the gasket holes....assuming you have done the same with the heads on the engine already....

I am running an air gap performer rpm with the PCV going to the small spacer....to keep the fumes spread into all 8 ports.

to each his or her own

 

[kensblue65fb]

Aren't the cobra, and edelbrock F4B. intakes, very similiar to the performer RPM. Also have you seen the manifolds available from Power + Plus. They look like the old Shelby ones. What are the advantages of one of these manifolds over the Performer. Engine is basically stock, and doesn"t see much duty over 5400 rpm. Looking for torque over top end performance. I'm open to any advice Thanks !

 

[camachinist]

I would put the Cobra and F4B somewhere in between the Performer and Performer RPM in performance on a mild engine. If you're planning on more camshaft, compression, better heads, etc, along with more gear, looser converter in the future, get the RPM. I run one on the race car and am quite satisfied with it.

Conversely, I run an original Cobra manifold on my D-coder, which has a totally stock engine, and am quite satisfied with it as well. It's a little bit more cold-blooded on winter days but nothing a bit of choke adjustment can't manage. Good all-around torque up to 4.5K or so, which is all I dare take the old rebuilt to..*G*..big difference over the stock D-code CI manifold.

Hope that helps!