having some custom headers built for my 300 engine. What is the best diameter to go with? I have a 4 barrrel . I understand the bigger the diameter the less low end power. Will put an x pipe thereafter. Thanks
Probably a 1 5/8 tube would be good on the smaller cube engine like that and would allow u a little room to grow if u ever step up to a 340 or mod the 300. I run Sanderson shortys on my 67 340 and they are a tremendous improvement over the junk manifolds!
'Headers by Ed' was once the guru on header design. His catalogs gave lots of great info on header design..... choosing proper diameter and length. His webpage might still have some of that info, check it out: http://www.headersbyed.com/
What are your future plans for your little sbb 300? Are a set of heavily ported TA Rover heads in the plans? What about adding a sbb 350 crank in your sbb 300? Without adding cubes or better flowing heads you don't really need anymore than 1 1/2" headers. Even if you were to step up to a sbb 340 with factory heads, 1 1/2" would still be enough because the factory heads just don't flow but the 1 1/2" headers will still out flow the factory manifolds that are the same for either the sbb 300 or the sbb 340 IIRC. Derek
I'd go with 1 1/2" for 300. My 406 has 1 5/8" and gained only 5hp at peak and gained absolutely nothing in TQ with 1 3/4", so I stayed with the 1 5/8". Bigger isn't always better with headers
"Headers by Ed" is still very well known around here as top experts. They can build headers for about anything.
