Gt40p header conundrum.

[jjltthomas]

Ive got GT40p heads on my engine, not realizing there was an issue of available headers. Has anyone worked through this without using the p headers? Ive heard there are certain regular headers that you can slightly indent one of the primaries and it works. Also that certain headers wont even work that way. Anyone with good experiences weigh in please.


Sent from my iPhone using Tapatalk

[Haystack]

Ive seen guys use stock 87-93 headers. Other people use bbk's or the ford racing "p"specific header.

There really are a ton of options out there, people just give up way too easy.

[ZephyrEFI]

I used the Ford Racing P shorties because I didn't want to wonder if they would work, and they are affordable, so why not?

Sent from my XT1650 using Tapatalk

[86FOX4EYE]

I used the Ford Racing P shorties because I didn't want to wonder if they would work, and they are affordable, so why not?

Sent from my XT1650 using Tapatalk

Are these still available?

[ZephyrEFI]

Are these still available?

American Muscle has them.

[86FOX4EYE]

American Muscle has them.

I see the MAC version and I think JBA makes a P version as well but I think the Ford Racing headers are out of production. I could be wrong but I couldn't find any a few weeks ago.

[ZephyrEFI]

I see the MAC version and I think JBA makes a P version as well but I think the Ford Racing headers are out of production. I could be wrong but I couldn't find any a few weeks ago.

Oh, weird, you're right! I tried googling Ford Racing GT40P shorties and a direct link came up, but if you navigate there manually, they're not there! Sorry about that!

[brianj]

BBK unequal length shortys, no real issue.

[jjltthomas]

Ok. Thanks. I was worried about that good ol' changing plugs. I love BBK headers so probably what I will go with.


Sent from my iPhone using Tapatalk

[STL79Coupe]

On my engine the only problem with removing plugs was on the 7th cylinder. I had to cut a socket in half to about an inch long, and welded a handle on it. This was for the socket to slide over the plug since it was close to the header tube. The headers are BBK 1 5/8 long tubes.

[bwguardian]

I had the MAC units on mine that worked...but like with most others (see picture in post #4 by brianj) one will have to utilize 90* boots on the spark plug wire boots. I seem to recall most long tube headers will work. I wound up finding some Ford Motorsport stainless units and have been really happy with them.

[STL79Coupe]

Yeah I forgot about the 90* boots. Another friend used the cheap ebay shorty headers and they clear like a dream.

[jjltthomas]

Your using longtubes and they work. Im interested in that.


Sent from my iPhone using Tapatalk

[cb84capri]

Well, my 1-5/8" ceramic coated BBK longtubes had huge nasty welds inside of the header flanges, a primary tube on the drivers side came in contact with the steering shaft and needed some hammering, the tubes on the passenger side hit my Mcleod bell and i had to beat the primaries and grind the block plate and bell, the clutch cable is close to the header on the driver side and needs a heat sleeve over it and the starter will need to be wrapped too. The H pipe had to have the hangers cut off of it because they weren't even close to reaching the hanger at the trans, and I had to spread the headers when they were on the engine to get the h pipe on. BBK uses crappy flanges on their h pipe which willl pull over the ball sockets, so you'll want to replace them with split flanges. I don't have much good to say about mine anymore, except that they quieted down the interior a lot during highway cruising over the BBK equal length shorties I had on it before (which are spark plug wire killers) and made the engine sound meaner. I didn't install them on p heads but these issues should still apply. I wouldn't buy them again. Actually, for what I do with my car, I'd buy big shorties and make it easier on myself when I have to service the clutch. There's no way I can get the bell off in chassis without removing a header. The provided gaskets were junk. Mind you I did buy these years ago, they may have made revisions since, but I doubt it given how long these have been on the market.

Ca;e

[STL79Coupe]

Wow! I didn't have any problems like that with my long tubes, but I use oldschool ASP solid alum motor mounts which raise the motor a bit for steering shaft clearence. I also just have the stock bellhousing for my T5. I agree with any of the supplied header gaskets always seem to be junk.

[soldknow]

I have the BBK long tube headers on my 302 with gt40p heads and had issues with getting the plugs in. Had to buy shorty plugs which are not cheap but fixed the fitting issue & worth it


Sent from my iPhone using Tapatalk

[Supersonic G.T.350]

I've heard multiple times that the 1-3/4" fit better than the 1-5/8" primary headers, even better on P heads.

[STL79Coupe]

I have the BBK long tube headers on my 302 with gt40p heads and had issues with getting the plugs in. Had to buy shorty plugs which are not cheap but fixed the fitting issue & worth it
Really? On what cylinders? I have the same headers and have no issues putting in regular autolite pulgs. The combo is in my son's 84 now ith multiple plug change and no problems.

Sent from my iPhone using Tapatalk

I've heard multiple times that the 1-3/4" fit better than the 1-5/8" primary headers, even better on P heads.

Yeah the bigger tube goes out straighter for a better fit.

[mcb82gt]

Ive "heard" the BBK unequal shorties work with 90 degree plug wires. I think that is the route I am going to try. I don't like the individual flange MAC headers, or the price of them.

[Broncojunkie]

Edited: gave wrong info. Thought my set was bbk but I was mistaken. Sorry.

[Broncojunkie]

Ok I believe these are Mac headers. Can anyone confirm? I gave them to a buddy of mine recently and he's using them on his gt40p's. Just thought I'd post a good pic for reference. 90 degree boots with a heat sleeve on the rear plugs and he should be good to go.



Edit: No, he's not using the OEM springs. He was just throwing these on to see how they fit. He's actually in the process of putting on/ setting up the Trickflow spring kit as we speak. He lapped the valves, cleaned/painted the heads, etc. Hope to have the engine sitting in the car next week.

[STL79Coupe]

Yes those appear to be MAC's. They don't have a one piece header flange like most others. On my P setup I only had a close primary on the 5 cylinder, but i had BBK longtubes.