New Crate Motor-Manifolds vs Headers

[35boulder]

Posted this in the wrong forum earlier. I'm needing to replace the tired 307 in my '69 SWB. Was wondering if any of y'all had used a new set of exhaust manifolds on your crate motor install instead of headers. I'm not building a hot rod just an in town truck. Thanks for any info.

[Ziegelsteinfaust]

Exhaust manifolds are a good choice if your more.concerned about noise. Rather then the most HP possible.

Yet there are exhaust manifolds easily available that help you get some of the best of both worlds. At least on mild/warmed up engines.

The traditional Corvette ram horns, but you need to notch your cross member.

Another fine choice is 96+ Vortec 350 exhaust manifolds from 1 ton trucks. You have to check, but in a circle track magazine which I read. Mentioned they were good, but I forgot the exact application.

[68 P.O.S.]

Stock style exhaust manifolds flow very well and are completely acceptable for your needs since it sounds like its going to be a mild engine. With a mild engine you likely won't notice a difference between the two. If you go with headers, get a quality set like Doug's Tri-Y's for torque, don't get a cheap $99 set or you'll have nothing but problems.

[MARKDTN]

On a stock crate motor, manifolds are fine. Also less likely to leak IMHO.

[Grumpy old man]

Unless your constantly over 5,000 rpm headers have nothing on rams horn manifolds . You don't have to notch your cross member to run 2 1/2" straight drop rams , no issues with leaks or spark plug access .

[toolboxchev]

Originally Posted by Grumpy old man

Unless your constantly over 5,000 rpm headers have nothing on rams horn manifolds . You don't have to notch your cross member to run 2 1/2" straight drop rams , no issues with leaks or spark plug access .

Nice Work Grumpy! And how true....

[35boulder]

So Grumpy, did you purchase some new manifolds from Summit etc?

[Mhussnatter]

Originally Posted by Grumpy old man

Unless your constantly over 5,000 rpm headers have nothing on rams horn manifolds . You don't have to notch your cross member to run 2 1/2" straight drop rams , no issues with leaks or spark plug access .

Grumpy
Hope you are doing well buddy. Question for you in regards to the above. I am trying to decide on headers or the ram horn straight drop manifolds you mention... BUT I have a newly built 383 Stroker putting out about 420 HP. Would you still recommend the ram horn manifolds over headers? If so I am thinking of ordering ceramic coated ones ... Thanks man.

[Sheepdip]

A lot less issues with stock manifolds...just my 2 cents worth.

[c10Eric]

Hey guys - I've got a 68 c10 with a 350 crate motor... and was thinking of replacing the stock manifolds (one side's got a leak) with some new shiny ones. Any suggestions on what ones I should be looking at?