69 292 Exhaust Manifold

[Doubletrouble]

I've got a 69 Chevy C-20 that is my workhorse...pretty much stock. I replaced the 292 engine with a rebuilt 292 some 22 years ago and the exhaust manifold was cracked. I put headers on it and they have worked well. However, I am going through exhaust gaskets right and left and am thinking about going back to a stock exhaust manifold and exhaust. I have had to double gasket since the beginning (Mr. Gasket #155). The engine that is now in the truck is a 71 or 72, I believe, although the intake is from the original engine. I found this exhaust manifold on ebay: http://www.ebay.com/itm/65-66-67-68-...#ht_1215wt_791

However, I don't know if it will work on my earlier model. The intake is stock and the stock tranny is a 4 speed transmission. Any thoughts or suggestions would be appreciated. Thanks!

Al

[Wrenchbender Ret]

The 250 & 292 exchange. The early ones had a 2 bolt flange where the ex pipe fits it. The later ones had 3. You can use either by changing the flange on the pipe. The 292 are hard on manifolds & gaskets as there exhaust is extremly hot when working hard. Its best to get a manifold from a 250 in a 1/2 ton or car. I would be leary of that one on e-bay. You dont know the condition of it. Often the studs are broken off when they are separated from the intake. The price is way too high also.

[Doubletrouble]

Thanks for the information. I guess I'm going through the gaskets because of the heat that is generated under heavy loads. I'll keep looking for a good exhaust manifold....

Al

[68 IRON]

First off, welcome to the best truck site available. Dont sweat the one on ebay....its missing the heat riser. Without it you would just bake the intake and it would run real rough until it cools down. Keep searching around for a manifold...they pop up once in awhile. Oh ya, if you have pics of the exhaust it would really help. You never know it could be something else causing the problem.

[70cst]

Hey Doubletrouble ...

Just wanted to say to your new internet truck forum and from Ohio

[Doubletrouble]

Thanks to all! I'm hoping to get to removing the blown gasket this coming week and I'll get a pic and post it. I do know that when I went to the headers, she will hesitate on acceleration because the intake is no longer being heated. It's not terribly bad, but it does occur especially when shifting gears. I'm looking at aftermarket intakes that have the coolant running through them (ie. Clifford Performance), but then I have to get another carb and whatever linkage modifications. A lot of money for a truck that only gets about 800-900 miles per year put on her! I can live with the hesitation for a bit longer!

Does anyone know where I can get the correct intake/exhaust studs/bolts? I've been told that could be part of the problem if they are "stretched".

Al

p.s. 68 Iron, I actually purchased the truck in St. Helens, OR back in 1989 when I lived in Kelso. It was delivered from the factory there and was a farm truck for 20 years. I don't miss the rain from the Pacific Northwest, but I do miss the green!

[VWNate1]

WELCOME AL !! .

New ones are available , about $250.00 .

The proper studs are available in any Hot Rod shop , here in California (land of Fruits . Nuts & Flakes) , Pep Boys has them in the " HELP ! " aisle .

Dorman Manufacturing makes them & they come in sets of three with the correct hard to find , tall brass nuts .

My 1966 292 has the three stud exhaust flange and no heat riser .

My 1976 GMC C-2500 292 has the two stud flange and no heat riser .

Your flat spot is most likely caused by an intake vacuum leak or improper tuning .

Removing an old exhaust manifold is tricky and takes a special touch .

I can detail it if you wish , you'll need an Oxy / Acetlyne torch to do it properly .

[slomotion]

I may be assuming here, but I'd guess your headers are steel? I put a set of Langdon cast iron headers on my 292 four years ago with stock gaskets and they haven't leaked yet, (quick! where's some wood to knock on?) I believe the longevity is because the cast won't distort under the heat like a steel header will. I put never sieze on the gasket faces to minimize the scrapeing if I ever need to open up the system.

Welcome to the board!

[68 IRON]

Here ya go Doubletrouble.....http://www.34-chevy.com/ These guys have a lot of stuff.

[Doubletrouble]

Slomotion, will the cast iron headers require me to change out my stock intake manifold?

Thanks for the link 68 Iron...I see some parts I'm going to order right away!

Al

[slomotion]

I don't want to mislead you by guessing, but you can contact Tom directly at:

theboss@stoveboltengineco.com

I used mine with an Offenhauser intake that was advertised as a replacement for a stock unit, so my gut feeling is they would. (The headers are a split set.)

[68 IRON]

Those cast headers would be nice on a 292....they sound good too. I think someone makes a water jacket adapter for stock manifold heat. Who knows, maybe its just an accelerator pump....? When you get time lets see what you got....these guys (myself included) love pics!

[54blackhornet]

DT, If you are going to run a 292 you need Tom Langdons cast iron headers ! Do not use tube headers, I guess you know they will leak ! and if you run her hard even a stock manifold will wear out. Tom is great and you can talk to him easy nice guy. he has been working on 292's all his life, great engine ! have one in my 68 GMC.............

[Doubletrouble]

OK guys...got the headers off and you guys were correct. The tube headers have warped...I verified it with a straight edge. It's very slight but it is only on the one tube where the leaks keep coming through. I contacted Tom and found out that the cast iron headers will indeed fit with my stock intake in place. So, I'll order one of those up along with new bolts/studs.

I tried getting some pics today, but the camera is acting up in that it won't focus in. It's pretty old, so probably time for a new one of those too!

Now to find one of those water jacket adapters that fit on the underside of my stock intake. I've read a bit about those but none of the articles state where to find them. Maybe when I call to order the headers, they'll know.

Thanks again guys. I REALLY appreciate it!

Al

[Former member Yoder213]

Tom's got the heat plate to fix the intake heating issue, I just got my cast headers from him and I ordered the plate with it. tis and extra thirty, and a maybe a little over priced, but worth the piece of mind. besides, how else would you seal up that hole?