Intake Manifold Recomendations

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Mar 30, 2009 | 02:32 PM

DaJesterMan

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Racer

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Intake Manifold Recomendations

I have a 427 with a single plane manifold (Victor Jr.) and I am looking for a high rise dual plane replacement to make the engine more street friendly. What manifolds do you guys prefer. I have a Holley carb and hood clearance is not an issue (see profile picture) I am not sure what kind of heads are on the engine or the shape of the ports, but any advice would be a big help.

Thanks!
-ks

Mar 30, 2009 | 02:51 PM

Vette79C3

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From: Millersville, MD

Knowing the type of cylinder heads and whether you have headers and/or dual exhaust would help???

Mar 30, 2009 | 03:05 PM

DaJesterMan

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Where do I look to find out the head type? I have Hooker sidepipes installed now...

Mar 30, 2009 | 04:33 PM

TheSkunkWorks

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From: Graceland in a Not Correctly Restored Stingray

If you have a Victor Jr. 454-O (Edelbrock #2904) you should have oval port heads, in which case I recommend an RPM Air-Gap 2-O #7561.

If you have a Victor Jr. 454-R (Edelbrock #2909) you should have rectangle port heads, in which case I recommend an RPM Air-Gap 2-R #7562. This is most likely the intake which will be going beneath an 850 Mighty Demon on my latest solid roller, alum head 427 build.

Or, you could pop a valve cover and give us a head casting number...

Of course, if you've considerably too much duration, changing to a dual plane isn't necessarily going to cure your streetability issues. Thus, it would be good to know your current cam / CR / carb combo.

TSW

Mar 30, 2009 | 05:44 PM

Ganey

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From: CORVETTE 77 385 C.I. TEXAS

Quote:

Originally Posted by TheSkunkWorks

If you have a Victor Jr. 454-O (Edelbrock #2904) you should have oval port heads, in which case I recommend an RPM Air-Gap 2-O #7561.

If you have a Victor Jr. 454-R (Edelbrock #2909) you should have rectangle port heads, in which case I recommend an RPM Air-Gap 2-R #7562.
Thus, it would be good to know your current cam / CR / carb combo.

TSW

Yes.

Mar 30, 2009 | 06:58 PM

DaJesterMan

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Racer

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Thanks for the advice! I have no idea what cam is currently in it. Is there anyway to identify it short of pulling it out of the engine?

Mar 30, 2009 | 07:19 PM

TheSkunkWorks

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From: Graceland in a Not Correctly Restored Stingray

If you've ever degreed a cam, it shouldn't pose too much difficulty. With a full 360* indexed damper or damper tape and driver's side valve cover off, if you have a dial indicator and are handy with it you can set up on #1 intake and then #1 exhaust retainers, parallel with the valve stem, and extrapolate duration, lift, LSA and ICA within reasonable accuracy for these purposes.

For advertised duration, with a hydraulic cam you can plot from ~0.003-0.006" lift, and I'd suggest ~0.015" lift for a solid. Also, be sure to plot either type of cam at 0.050" lift for @ 0.050" duration. Lift should be straight forward enough, but if you have any trouble doing so yourself, give us the degree readings for the intake and exhaust opening and closing events and I/we can cipher your approx. duration LSA and ICA specs for you. Short of removing the timing cover and hoping for a grind number behind the timing gear or pulling it to have it properly graphed, I don't know of better method.