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hevychevy
04-18-2019, 05:32 AM
Have a 283 built for my 57 Bel Air and we're having a debate on the aluminum intake setup. My buddy wants to sell my his Edelbrock (don't remember the number) that we used when we broke the engine in on the stand. Lunati voodoo cam, Power Packs, headers; ran sweet and showed tremendous throttle response due to cam and manifold I think. Problem: The manifold will not clear the road draft canister in the valley. I found an adapter used on later Chevelles which fits the road draft hole. It allows the hookup of a PCV valve. I want to use that setup. Buddy says to pull the canister out of the valley. Don't need it. I have read, without the canister I will suck oil out of the valley. Any opinions on the canister. I say it's there for a reason. I believe the Edelbrock2703 intake will clear the canister and want to use that. Called Jegs for tech help and the guy said put a pcv valve and breather in the valve covers and block the road draft pipe hole. Don't want that look. What do you guys think?

BamaNomad
04-18-2019, 05:35 AM
If you implement a PCV, you shouldn't need (part deleted) road draft tube (which is just the old way of venting the engine). You can plug the hole at the back...

Correction: As Rick stated in a later post, you WILL need a canister to separate the liquid oil from the vapors...

hevychevy
04-18-2019, 06:10 AM
Thanks for the reply, but what if I intend using the road draft hole at the back of the block for my pcv? I know a PCV in the valve cover is a simpler solution but it destroys the old school 283 look. Thanks in advance for any additional help.

Rick_L
04-18-2019, 06:49 AM
I disagree. That "canister" is an oil baffle designed to keep the road draft tube from pulling liquid oil from the engine. It serves the same purpose when a pcv valve is connected there instead of the road draft tube.

Later model Chevys connect the pcv to the valve cover, but the factory valve covers have a similar baffle, though smaller. Engines from the mid 60s that used the setup you are proposing still had the canister. The original engine from my 67 Nova was this way from the factory.

Those who've used aftermarket valve covers with an insufficient baffle to connect a pcv valve can attest to the problem of liquid oil being ingested into the engine.

The canister does not fit under many aftermarket manifolds. Sometimes you can take a hammer to the top side and flatten it where it interferes. Sometimes the aftermarket manifold will have a rib there that can be removed to help with clearance.

BamaNomad
04-18-2019, 06:55 AM
Rick is correct! Rick Thanks for correcting me...

markm
04-18-2019, 03:46 PM
Keep canister find a intake that fits, old school SBCs are cool.

hevychevy
04-27-2019, 07:32 AM
Update on previous post from 4/18. The guy who is helping with the 283 build, and I are at serious odds on intake man. and vent system. First, he is insisting on a Holley Street Dominator intake man. I'm hearing they are high rpm manifolds and not a torker type manifold. The Lunati Voodoo cam specs indicate this is a low end torque cam making peak torque around 3500 rpm. I don't think the Holley intake is a match for this cam. Your opinions? Then, he says we vent the crankase by installing a breather in the oil pan and connecting it to a header tube. He says the exhaust will creat a vacuum to relieve crankase pressure. Never heard of this. This has gotten so complicated I am thinking of just using the stock iron mainfold, with valley cannister left in place and running a pcv valve from road draft tube hole, with vented oil filler tube cap. I already have the fitting for the pcv/road draft conversion. First, do I lose a lot of performance with the iron manifold? Also, does anyone know of an aluminum intake that will clear the cannister? Sorry for being long winded, but needed to give you all the details.

Rick_L
04-27-2019, 09:41 AM
A Holley Street Dominator is a low/medium rise dual plane manifold similar to an Edelbrock Performer. They are a good choice for a torque type application. Holley lists it as good for idle-5200 rpm. It would be a step up from the iron manifold without going overboard. I don't have any idea if it will clear the canister.

Using the exhaust as a vacuum source for ventilation isn't going to work on a street engine. There won't be any vacuum at idle and cruise where you will spend most of your driving. This deal only works on a race car with WOT. The oil pan isn't a good spot for the breather, too much chance of sucking oil out. Go with your original deal with the pcv plumbed into the road draft hole.

There are manifolds that will clear the canister but I don't know which ones. Some have a rib that you can remove to make it fit also. A really old aluminum intake that was being made back in the 60s would probably have a better chance of clearing, but no guarantee.

Gmvette
04-27-2019, 01:27 PM
As suggested an older 60’s aluminum manifold such as from a 350 HP 327 Corvette will fit and give as good as performance as any.

markm
04-27-2019, 03:30 PM
A Holley Street Dominator is a low/medium rise dual plane manifold similar to an Edelbrock Performer. They are a good choice for a torque type application. Holley lists it as good for idle-5200 rpm. It would be a step up from the iron manifold without going overboard. I don't have any idea if it will clear the canister.

Using the exhaust as a vacuum source for ventilation isn't going to work on a street engine. There won't be any vacuum at idle and cruise where you will spend most of your driving. This deal only works on a race car with WOT. The oil pan isn't a good spot for the breather, too much chance of sucking oil out. Go with your original deal with the pcv plumbed into the road draft hole.

There are manifolds that will clear the canister but I don't know which ones. Some have a rib that you can remove to make it fit also. A really old aluminum intake that was being made back in the 60s would probably have a better chance of clearing, but no guarantee.

Most intakes clear it fine, as far as Street Dominators go they come in two flavors single and dual. If we are discussing the dual I agree with Rick. I would pass on single plane.

Rick_L
04-27-2019, 05:20 PM
Well I'm sure a 350 hp 327 aluminum manifold will clear the canister because those engines had one. Thing is if you have one of those manifolds or acquire one cheap, you should enrich yourself by selling it to a purist. Then go get something else that works and pocket the extra cash. Same would go for any aluminum manifold which originally came on a 340 or 365 hp Corvette 327.

scorpion1110
04-27-2019, 05:35 PM
Come on Rick, the least you could do is recommend an SY1. Its cool and you might wind up that little 283 a little. ;)

9674

I am still trying to decide if I want to go through setting one up all over again.

Yeah slightly off topic...

Scorp

markm
04-28-2019, 08:24 AM
Well I'm sure a 350 hp 327 aluminum manifold will clear the canister because those engines had one. Thing is if you have one of those manifolds or acquire one cheap, you should enrich yourself by selling it to a purist. Then go get something else that works and pocket the extra cash. Same would go for any aluminum manifold which originally came on a 340 or 365 hp Corvette 327.

My backup SBC for my 74 Z28 still uses a early Z28 highrise as well as my 67 SS 350. You cannot beat those things, if I were try it would be with an RPM airgap.

hevychevy
04-29-2019, 07:22 AM
Thank you for the info gentlemen!