[LUST01]

I use Craftsman angled open end ignition wrenches. I also pull the starter and oil filter adapter to get more room.

[jrh3405]

First off slot all the header bolt holes, cut gasket to fit each port individually except middle ports,now start bolts in head, slide header in from bottom,now slide header over your bolts, drop in gaskets n tighten up.FWIW, Jim.

[screamingchief]

IMHO,all D-port headers should be made using the sub-flanges like the big tube D-port headers use (hedman,maddogs),that would solve most all these issues in one fell swoop.

If you've ever installed a set of those "sub-flange" style headers,you'll most likely agree with me on this.

[1967Tempest]

I have to attempt this... again.... I got the copper gaskets. I might try one of the new flange cutting ideas. Looks like a good mod. If I could install a set of headers after they were cut in one day... Seems like it would be worth it.

Dave

[Mark C.]

I've also had very good luck with cutting the flanges. The bolts are easier to get at. I don't have any leakage issues either, etc.

Plus FWIW, I think they look better/cooler.

[1967Tempest]

ALL:
Pontiacman1970 is a genius. He sent me a PM telling me to get part # ARP 400-1108. Hedder bolts with a 5/16 head.

Long story short, I started today at 6:15 and finished both, with putting the starter back in by 9:00. Less than 3 hours!!!! I remember taking a WHOLE 12-15 hour day trying to get the driver side hedder on.

I found out the reason for my exhaust leak. As with every oil change I make sure to tighten all exhaust bolts. But the 4th and 5th bolt on the driver side never got tightened. So the bolts almost fell out. Lesson learned.

Thanks again!!

Dave

[Pontiacman1970]

Dave,

Your welcome Ed

[1967Tempest]

Well here is another lesson learned. I ordered the copper gaskets. If they are dead nuts on the header flange and the gasket, geuss what....... they leak. I ordered a new fel-pro set that are the fiber with the steel core. I should have just done it that way to begin with. Oh well, at least I can get the headers out and replaced in less than 3 hours.

[AllRise]

Okay, this may be a silly question, but needs to be asked if I plan on learning anything.

So I have my 455 out of my 73 formula, and am planning on putting RAIII exhaust manifolds on in place of headers due to access and leakage. Since this motor will be shifted at 5000-5200 am I going to see any major losses by just going with the factory manifolds?
I am no stranger to header gasket changes on an A body, but the F body cars are m f-ing insane! And it doesnt help that I have banana hands either. If it will produce better results though, I am willing to suffer through with the headers. I was under the impression that since I have more of a torque, and less of a hp combo, that I really wont be losing much on the street, or on the track. Is this a correct line of thought?

[LUST01]

Originally Posted by screamingchief

IMHO,all D-port headers should be made using the sub-flanges like the big tube D-port headers use (hedman,maddogs),that would solve most all these issues in one fell swoop.

If you've ever installed a set of those "sub-flange" style headers,you'll most likely agree with me on this.

I wanted to go with the sub flange style Hedman Hedders in my 69 GTO with d-port heads becuse of the larger tube and collector size and the easier installation but they no longer have a listing for 68-72 A-bodies (Hedman also no longer as a listing for round port 68-72 a-bodies). I went with Hooker Super Comps for d-port 68-72 a-bodies and that fun center bolt. That was a few years ago and the Hookers need to be replaced. The only company that currently makes the large tube/collector for the d-port 68-72 a-bodies is Maddog. They are a multi-piece race header with a slip on collector and one tube on each side goes over the frame. I do not want to cut my fender wells to fit this style header plus the multi piece design sounds like would be a pain to install. I notice Hooker and Doug both have 1 piece large tube/collector headers for round port 68-72 a-bodies. Does anyone forsee any problems installing one of these headers using a Hedman style sub-flange? If no sees any problems I might go this route and make my own sub-flanges. (I have access to a water jet machine at work)