Thread: Ramshorn exhaust manifolds on Vortec heads

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My '53 Chevy pickup is nearing completion of mounting the engine. While rebuilding the engine, I found a pair of new Vortec heads and installed them rather than the fuelie heads the engine originally came with. I bought a breaker ignition distributor and converted it to an electronic ignition for an older look. Plus, the smaller distributor will not hit the firewall. My old Rochester carb will top off the engine.

I found a pair of ramshorn exhaust manifolds to go with the old school theme and when I mounted them, I found they ride too high on the Vortec heads and actually hit the valve covers. I heard that ramshorn manifolds are restrictive and that I should use block hugger headers and forget old school look altogether. I don't like headers and really don't, at age 69, need as much power as I can get out of the small block. I have the newer style manifolds that I could use but I prefer the ramshorns.

I dropped the engine into the engine compartment and also discovered that the ramshorn manifolds are very close to the frame rails(less than half an inch on either side) and I fear that with acceleration, the manifolds may actually hit the frame.

I would like to know if the ramshorn manifolds are restrictive and if anyone has used them with vortec heads? I saw a spacer online that claims to rectify the mounting problem but I know the spacer would cause the manifolds to hit the frame. Any opinions about Rochester carbs? I personally like them because of the small primaries and huge secondaries.

Thanks for any replies. You folks have helped me in the past and I value your opinions and advice.

Starlightcoupe(my dream car)

There must be some difference in the Vortec vs regular heads, because when I ordered my Sanderson Headers I forgot to mention Vortec. Then I called back a week later and told them, and the girl said "Oh, thanks for telling us, yes they are different, and I will put that note on your order." I don't know what that difference is though.

I just looked at the Speedway catalog for you, because they are selling new ramshorn type manifolds, and they only say "small block chevy" and make no mention of Vortec or not. You might call Speedway and get a tech guy on the line and ask.

As for the Rochester Q-Jet, they are very good carbs, and very much overlooked. Millions of marine engines have them on 350 Chevy engines, and they work great. I suspect the fuel economy is better too with those small primaries. I have always put a mark on my boat's throttle control at the spot where the secondaries start to come open, and stay below that spot, and have gotten good milage. I think hot rodders tend to thing Holley or Edelbrock, and have overlooked a very good street carb in the Q-Jet.

Don

I will call Speedway and inquire about the Vortecs. The local Chevy dealership is a laugh for technical advice. I will go with the Rochester Quadrajet. One rodder told me the reason he didn't use the Q-Jet is because the Q-Jet bowl empties with hard acceleration but the Holley doesn't. I know that Ford used the Q-Jet on the '69 429 engines because they could deliver the $.50 gas better.

Thanks again for the advice.

Vortec Heads....................

http://www.superchevy.com/technical/...0511sc_vortec/

Thanks for the article link. I have the older Vortec heads. I just spent an hour in the garage putting shims between the manifolds and the heads and found that my ram's horn manifolds will barel fit between the frame rails of the Chevy. I will use the later model manifolds because they don't have the bulge on the lower end or I will get block hugger headers.

Thanks for the post. Incidentally, I had a '57 and paid $3393 for it new. It had every option Chevy offered and a 283.