Header tube for 327-350
 

What length do most use for the primary pipe for each engine and collectors

Re: Header tube size for 327-350
 

Must be top secret. Or there's not a Chevy on this site.

Re: Header tube for 327-350
 

You will not get a straight answer because the question is open ended.
There are too many variations of Chevy 327 and 350 engines throughout the years. Some 2-bbl and others 4-bbl, not taking into account the FI engines.
The requirements are also effected by the type of cylinder head, compression and camshaft specs.
If you have a specific engine year and horsepower rating, you might get a response.
I you are curious, you can also purchase a copy of the PipeMax software and put your specs and it will break down the header requirements for the particular data you enter.

Re: Header tube for 327-350
 

Burns stainless has a form you can fill out & they will give a recommendation, for a price I think, & yes Pipemax.

4-2-1 or 4 into 1? I built a set of 4-2-1 for my 421 street engine but never tested against anything else.

Re: Header tube for 327-350
 

Just remembered I have an old "Smokey" book, I'll reference that. Thanks anyway.

Re: Header tube for 327-350
 

What's your combination? -Al

Re: Header tube for 327-350
 

I try to answer most questions, provided I have useful input.

However, if the question does not include anywhere near enough information to allow for a useful answer, I usually simply do not have time to write out a list of things needed to give a useful answer.

Re: Header tube for 327-350
 

Ok... I don't think the tube length on my 340 Engine is right, I think they build too long a pipe. All I want is just a general size for the 3.25-3.5 stroke crank, since after 60 years someone should have it pretty close give or take a few inches, not trying to fine tune to the 1/4 inch. How about 66-327 Chevy 2, 69 Z-28 302, 70-1/2 Camero Z28-350, all running stock. I had off the shelf pipes on them then but can remember what size after all this time. Just a good starting point to compare. Thank you

Re: Header tube for 327-350
 

I use off the shelf Dynatech steps 1 5/8" primaries to a 3" collector. I'm sure there's more power to be found

Re: Header tube for 327-350
 

1-5/8 to 1-3/4 14-16 inches of each
With a merge collector for a 4 to 1 set up
or 1-1/2 to 1-5/8 for a tri-y will get you
In the game.

Re: Header tube for 327-350
 

Stroke is only one factor. There's port lengths, volumetric efficiency, RPM, and cam timing to name a few.

The suggestion that you buy PipeMax was a good one. Pays for itself on the first set of headers.

Re: Header tube for 327-350
 

Coleydog, Ron has given you good advice.

What body style/year are you working with? Also, what's your budget for headers? -Al

Re: Header tube for 327-350
 

That is good info, right along my thinking. My plan is to make up a set in reg steel (inexpensive) make adjustable, test, then do in SS. 70 Duster 340 (with the stock intake lol) E F or G. Still finishing up the cage but trying to get all my ducks in a row now. Info so far is helpful, thank you all

Re: Header tube for 327-350
 

If we are not doing steps we run 1 3/4 Primary 34 to 36 long and a merged
collector if budget allows....That is on both High and Low Comp. 340 Mopar
in Stock (E to G). I would generally expect a similar class 4 Brl. 350 to be
in the ball park with those numbers (Similar compression/Valve Size/HP/Wt.).