[MrWrestlingII]

I’ve got a couple threads going concerning a coolant leak and new exhaust.

http://forums.maxperformanceinc.com/...t=coolant+leak
http://forums.maxperformanceinc.com/...d.php?t=714536

I pulled my motor yesterday to address the head issue and will try to seal the pan again. I figure to have a number of questions while working on this project over the winter and decided to post everything in a single thread. I’ve pretty much researched everything to death, but there’s always the chance of getting a different perspective by posting here.

Header Flange Question
So to start with, I picked up a set of headers from the classifieds a few weeks back and bolted them up to check the fit with no gasket. Looking at the attached pic the header flange isn’t perfectly true, I suspect it’s common for the flange to warp a bit from the welding. I’m wondering if I should cut the flange to try and get a better seal or leave as is? The feeler gage in the pic is .015”, which is the widest gap with all the bolts tight. For installation I’ll be using a gasket (not sure which) along with high temp RTV.
Is there any disadvantage to cutting the flange between the inside and outside ports? I’ll be getting the headers coated and will want to cut the flange, if needed, prior to coating.

[bigborehunter]

O Reilly's auto parts sells some neat adjustable header bolts that work with an allen screw in the center. Allows you to adjust after initial fitting when heat cycle starts bending stuff around. The old version of this product had an irish name on it. It went off the market when some company bought them out. Then reappeared two or three years ago at O Reilly's . Just so you know...

[pfilean]

Would be nice to just get it flat to begin with and use a Felpro metal gasket. Maybe find a machine shop with one of those big belt sanders some use to true up heads without milling off a bunch. Probably what the header manufacturer should have done or maybe just didn't do enough.
Then there is a header gasket made by a company called Remflex (try remflex.com). At least if they are still in business. Material looked like it was made from a sheet of hard lead alloy almost 1/8 thick that had a lot of crush ability. I have had some luck with it but probably not in as severe an application as you may have with a built Pontiac.

[HWYSTR455]

Is there a reason you want to cut the flange? Why not just leave it as is?

.015 isn't jack, you should be fine with a gasket. I've had great success with the Mr. Gasket utra seal ones. Tighen, let it get hot, and tighten again. Keep tightening after a few heat cycles, and the flange should warp back.

Those are tri-Ys? Homemade or what make?

.

[MrWrestlingII]

Originally Posted by HWYSTR455

Is there a reason you want to cut the flange? Why not just leave it as is?

.015 isn't jack, you should be fine with a gasket. I've had great success with the Mr. Gasket utra seal ones. Tighen, let it get hot, and tighten again. Keep tightening after a few heat cycles, and the flange should warp back.

Those are tri-Ys? Homemade or what make?

.

I'd much rather not cut the flange but was wondering if the .015 gap was an issue. It sounds like I'm good.

These are the Tribal Tubes tri-y's. I picked them up in the classifieds a few weeks back and will be getting them out for coating next week.

thx

[HWYSTR455]

They look nice. What's the chassis, and how's the fit?

.

[MrWrestlingII]

Originally Posted by HWYSTR455

They look nice. What's the chassis, and how's the fit?

.

They're going on a 70 GTO vert, 4 speed. Still using the stock bellhousing.

I test fitted them before pulling the motor and they went in w/o issue after pulling the trans, bellhousing and oil filter housing. This was w/o raising the motor. I think the motor would've had to come up with the bellhousing installed. The oil filter housing needs to come off, but that's not a big deal.

[HWYSTR455]

Nice. And they're tucked up to the floor well and all? Shame they're not more readily available...

.

[Tom Vaught]

I have used Black "High Temp" RTV for many years to seal up HP engine's on the dyno with no leaks afterward. The Black RTV will easily seal .015" and the Metal to Metal contact with the head removes flange heat that would normally have to be carried away by the header tube.

A Win-Win situation. If you can get stainless set screws and nuts (McMaster-Carr) the fasteners will also live a very long time, especially with boosted engines. Stainless fasteners will handle much higher heat loads on boosted applications.

Normal Gaskets typically isolate the heated exhaust pipe from the head and unless you have a Mr. Gasket Asbestos type gasket (not likely) will fail over time. Single layer Metal Gaskets will seal until the fasteners see a heat cycle that loosens them up then they will count on carbon from the exhaust to seal the gaps. MLS gaskets are better as are beaded metal gaskets.

All that being said, I am a real fan of the Black "High Temp" RTV sealing method.

Tom Vaught

[blueghoast]

I've ran a weld bead on the sealing surface and ground it back down
as needed with warped headers if thats somthing you can do could
save ya some time and money. Good Luck.

GT.

[Gmpower dreams]

Originally Posted by Tom Vaught

Stainless fasteners will handle much higher heat loads on boosted applications.

Tom Vaught

Oh I would never use stainless on headers, to brittle and can lead to frozen bolts that break when you try to pull then out. We never use them at work. Water, heat cycle, three metals and a soft bolt? Makes me
just thinking about it.

[gearbanger]

Hey MrWrestlingII, I notice you have the tri-ys from Ron. I have been through this exact thing with them and I can tell you they will seal for a while but the lack of clamping on the ends will eventually cause them to leak. I talked to Ron and Aaron about this trying to give them some constructive feedback. They both told me that the pros build their headers with warped flanges like that to cause more clamping in the middle. What a joke!

Basically what I did and what they should be doing it taking a bench type belt sander to the flanges after welding. Not just a woodworking type sander. The kind you find at a machine shop. This trues them back up and makes them seal perfectly. It cost me about $40 bucks to have both headers done and they are within a few thousanths of perfectly flat now. Sadly, I did it after they were coated and had started leaking. If I were you, I would definitely do it now before coating them.

[gearbanger]

My headers were more like .040 to .050 though, so you can probably get by with .015, especially with the high temp.

[MrWrestlingII]

Originally Posted by gearbanger

My headers were more like .040 to .050 though, so you can probably get by with .015, especially with the high temp.

I've decided since I'm down for the winter anyway, there's no hurry in getting the headers coated. I'll run them to the machine shop and see what they have to say. There's no sense in not getting them trued up for 40 bucks.

Thanks everybody for the feedback, I'll be posting up with my other winter projects soon.

[MrWrestlingII]

I was at a head service shop for my coolant leak issue and talked to the owner about the header flanges. He took a look and felt too much material would be taken off the flange in order to true them up. The .015 measurement I took was with the header bolted down, so they’re further out uninstalled. If they were his he said he’d cut the flange but also said they’ll probably seal up ok w/o cutting by re-tightening the bolts a few times between heat cycles. I’m still debating on this one.

So my next project is installing an AC Delete box on the firewall. I’ve done some reading and it sounds like I can remove the inner fender w/o removing the fender. The plan is to remove the rocker and fender moldings, remove the lower fender bolts, tape the hell out of everything, unbolt the inner fender and try to rotate it towards the motor compartment and down. The car will be jacked up and the wheel removed. I really can’t say I’m looking forward to this job as I haven’t had the best of luck messing with body panels in the past.

[rad400]

Try Remflex gaskets the company is out of Wash. state. I have them on my car and work great. I have had blown out gasket with reagular header gaskets and collector gaskets.

[MrWrestlingII]

Originally Posted by rad400

Try Remflex gaskets the company is out of Wash. state. I have them on my car and work great. I have had blown out gasket with reagular header gaskets and collector gaskets.

I've seen the Remflex gaskets recommended in a number of posts and will check them out.

[MrWrestlingII]

I got the fender well out last night, it was a pain in the ass but do-able. The one thing I would do differently is, at least, remove the caliper and get it out of the way. The only real issue is getting that damn thing over the rotor/caliper. Before reinstalling I’ll remove the whole assembly down to the spindle. A little extra work but I think it’ll save some frustration in the long run.

The AC housing came off the firewall pretty easily. I had it off when doing a resto in the mid-90’s and used a weatherstrip putty my body guy recommended to seal it up, the stuff didn’t harden up at all. A quick test fit and the new AC delete box looks good. I’ll just need to scrape the remaining putty off and get the firewall cleaned up. I should finish this up on Sunday and will snap some pix.

Next on my list is replacing the master cylinder, which is leaking. The replacement doesn’t have bleeders and didn’t come with a bleeding kit. For bench bleeding, do you just leave the plastic plugs in and pump until there’s no air bubbles, or should I buy a bench bleeder kit with the tubes that run from the fittings back to the reservoir?

[MrWrestlingII]

Over the past couple weeks I’ve installed an AC delete box on my firewall and replaced a leaking master cylinder. Both jobs were fairly easy, with the hardest part being the removal/replacement of the inner fender well. Installation of the inner fender went better than the removal. Instead of removing both the caliper and rotor, as I’d planned, I first tried with just the caliper removed. This method worked good, not my favorite job but not too bad.

I’m now planning for a new Pypes exhaust system, 3” header to muffler and 2.5” tailpipes. After doing a bunch of searches and listening to different sound clips I’m seriously considering going with straight pipes as opposed to an X-pipe. I really like the choppy idle and old school sound of the straight pipes over the X. For a street car making far more power than can reasonably used on the street I don’t think I’d be giving up too much on this setup. If I decided differently down the road an H-pipe wouldn’t be too difficult to add.

Any opinions on this plan?

[mbwicz1]

For header bolts, I used ARP stainless ones (high strength, not soft like the hardware store ones), they have a small head and flange. Totallystainless.com is a good source for that stuff.

A/C delete looks good. I have a 3" x-pipe on tri-y's, 3" Goerlich mufflers, and 2.5" tails. Plenty of rumble, maybe a little too noisy around town, quiets down at highway speeds. If I was doing it again, I may have put 2.5" mufflers on it to see if it would quiet down a bit.

I have not run my headers enough to see if they leak, only about 300 miles. I probably tightened the bolts 5 times after running the car, used the thick carbon gaskets with a smear of red RTV on each side.

I would bench bleed the MC with the hoses that run into the bowls. Its only a couple of bucks to get a kit.

Have fun,
Mike