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Ford sb headers on a 318 poly?

Posted By: polkat

Ford sb headers on a 318 poly? - 09/02/10 07:48 PM

After some research, I've noticed that if full flanged Ford small block headers are finely centered against a 318 poly head, the two inside runners will be too wide by .040" each, forcing the two outside runners to be off by .080". So if a section .080" wide is cut from the center of the flange, and then the flange pushed back together and welded, the two inside runners will be a match leaving the two outside runners just .040" off each, which could be fixed with mild runner matching.

Then, if the flange is wide enough, or extra material is welded on, the flange could be drilled for the mopar bolt pattern (which is different).

If one already has the ford headers, and clearance (starter, steering, etc.) is not a problem, it seems like a cheap way to get headers for the 318 poly. Anyone disagree, or has anyone tried this? Thanks!
Posted By: cptn60

Re: Ford sb headers on a 318 poly? - 09/02/10 08:41 PM

Hmmmm. I was gonna try a set of 351-400 truck headers on my 66 d100. This could be another option also. Hopefully someone else will chime in.
Posted By: patrick

Re: Ford sb headers on a 318 poly? - 09/02/10 10:02 PM

how about either trying to purchase 318 poly header flanges (maybe from headers by ed?) or having some laser cut, cut the flanges off ford headers, and weld the new ones on?

of course, who knows if you'll have clearance issues with the torsion bars or steering box.....
Posted By: polkat

Re: Ford sb headers on a 318 poly? - 09/02/10 10:02 PM

I think it might be a viable possibility. Part of the problem might be any difference in the different head port sizes. If, for example, the header tubes are wider on sb ford headers, it might block being able to drill bolt holes in the flange for the poly pattern. I'm going to try it, but I agree that others might have better info, particularly those who have already tried it.

One post on another site suggested welding poly flanges on the ford flange and drilling through the poly flange, but that seems like extra and unneccessary work to me.

Most sites I have searched talk about adapting ford headers to the poly, but I have yet to find someone who has!
Posted By: cptn60

Re: Ford sb headers on a 318 poly? - 09/03/10 02:39 AM

Quote:

how about either trying to purchase 318 poly header flanges (maybe from headers by ed?) or having some laser cut, cut the flanges off ford headers, and weld the new ones on?

of course, who knows if you'll have clearance issues with the torsion bars or steering box.....


Possibly on a car you could have interference. On my truck there is plenty of room, maybe a set of moistbang 5.0's could work. Yeah there would be a port mismatch, but it may be an improvement. the 2barrel C/M headers I own have bigger ports than an A motor
Posted By: 65rbdodge

Re: Ford sb headers on a 318 poly? - 09/03/10 03:59 PM

i was going to do this many years ago. as far as i remember it was going to work. i did but some poly header flanges off of ebay, but never finished the project.
Posted By: Supercuda

Re: Ford sb headers on a 318 poly? - 09/04/10 01:10 AM

On a sorta related note, many years ago I saw a FWD Daytona converted to RWD with an LA motor in it. The owner used a SBC header with an LA flange welded on to fit the chassis. I have been looking at SBC headers that might be adaptable to my early A, way cheaper than TTI.
Posted By: crlush

Re: Ford sb headers on a 318 poly? - 09/04/10 03:46 AM

that would be great if they fit tti headers are nice but there worth more than the engine,hehe.
Posted By: wedgeheaded

Re: Ford sb headers on a 318 poly? - 09/04/10 11:54 AM

I bought a set last year at the NATS for $225. They're custom built and very nice. The look like the Spitfire headers in design. I saw several sets on e-bay for less after I bought these but not since.
Posted By: Anonymous

Re: Ford sb headers on a 318 poly? - 09/05/10 03:07 AM

Here's a set of 318 poly headers from the 50's (note the generator bracket on the passenger header). Ballenger brand; don't think they are still around

Attached picture 6178112-Ballengerheader318poly.jpg
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