Ram horn gasket solution

[72shortbed12]

I got a set of Dorman 2.5" ram horns ready to bolt on. Problem is I put a straight edge on the exhaust flanges on the motor and they're not flat. I checked the manifolds also and they're true.
Center ports stick out slightly more than the outers. Should I use a thick gasket with copper gasket spray on both sides?

Thanks

[Warrens69GMC]

If they are new return them and get another set that are true. You could have them machined flat as well.

[sjarrett71]

I use ram horns and they take donut gaskets, not flat ones. I don't know if the 2.5" are different though.

[Torrey72]

I have taken a belt sander to the center ports to level them before. This was when I was in high school with no money. It turns out nice, if you take your time with it. Now I would take them to a machine shop and have them decked flat. This is common for these to warp like your talking about. So I would just deck them. unless you can exchange them like Warren mentioned. If you bolt them up as is. You might have them crack over time. As for gaskets. I only use the metal stock style gaskets you can get at NAPA or most part stores. You can get better "crush" with these then you can with copper. This lets you seal up uneven surfaces better. Copper is only good if your mating surfaces are perfectly flat, in my experience. Also, Don't use the paper ones! A coating of ultra copper spray on each side doesn't hurt too.
These are the best I have found for ram horns Fel-Pro MS9275B

[72shortbed12]

Maybe I'll try the sander trick. Its the ports on the heads that are warped, the manifolds are true no issues there. The motor only has 15,000 miles on it. Bought it as a longblock from carquest a few yrs ago and have had a gasket leak. Kind of irritating to have a problem like this witha newer motor.

[sjarrett71]

DUH!!! I TOTALLY misread the post! Since you said 2.5" I thought you were talking about the collectors. Silly me, that's what I get for getting on the board as soon as I wake up in the morning!

[Torrey72]

Ok, the head is warped? Nice craftsmanship, I bet that engine was built in Mexico. Seriously. That part of a head should never be warped . No wonder it was leaking.
Be sure to stuff paper towels in the exhaust ports before you start. This will keep the metal dust out of the cylinders. Just don't forget to pull it out when done. And to help you sand it down evenly. Clean the outer edges of the ports with cleaner. The part that you would see orange engine paint on as well as the inner edge. And if for say the port was a 1/16 of an inch sticking out farther then the other ports. Take a black Sharpie and draw a 1/16 of an inch border around the outer and inner edges of the port you plan on sanding down. As you sand you can see how close and even you are getting as you sand the black edge down.

I hope that makes sense. good luck

EDIT: P.S. you can sand the manifold down to match the wacked out ports if that is easier too.

[screamin_c10]

The absolute last thing I would do is try and sand down the port's mating surface....

Go to Summit racing and get some soft copper or some good quality composite exhaust gaskets and be done with it....

Sanding down that surface is gonna cause you a lot more grief in the long run.

The correct fix would be to pull the heads and have them checked out and machined by a machine shop....

[Torrey72]

I agree in a perfect world. I first mentioned getting machine work done. But I think money is a tight here. personally, I would modify the ram horns before the heads. In this scenario. Exhaust is always more expendable and easier to deal with off of the truck. A little backyard machining work isn't really that big of a deal. Depending on how much material he is looking to remove. I would never advocate decking the block or cylinder head surface yourself. But this is as easy as doing a little porting and polishing at home. I have done this same thing back in the day. But if a person isn't confident in their ability to do something like this. I would encourage them to seek professional help. I rate this task two out of five stars on the difficulty level. What I did fail to mention in my last post was to finish off the work with a flat file. The sander was to just get you close to were you need to be. And to test the mating surfaces together without a gasket for fit. Sorry, it has been 20 years the last time I did this exact modification.

[screamin_c10]

Sorry Torrey, wasn't trying to step on any toes.... I just had visions of sparks shooting out from under a hood and a maniacal laughter filling the air...

I would think it would be difficult to maintain the correct angle with a belt sander with the heads in place. And if the heads were removed then a trip to the machine shop would be in order.

I do agree with the fact that it is crappy quality control and there is no excuse for this on a low mileage crate motor.

I have a low mile "Hecho" roller block that I am toying with building but it will be going in to the local machine shop for a once over and corrective action. I have heard horror stories regarding the machining of these engines at the factory.

[Torrey72]

Screamin C10, No harm done. I should really put more thought into offering advice that goes outside of what should be done to correct a problem. I know my skill level and tend to feel others are at the same. If I were to grind too far. I would just weld it up and grind some more. Back in High school I did allot of bracket racing at PIR and Woodburn. And that hobby is destructively expensive. When I would break something. I would have to find a creative way to fix it. At that time, Smokey Yunick was someone I Idolized. And that guy went beyond thinking outside the box. Doing what you should do to fix a problem was rarely in his vocabulary. There was always a different way with that guy. That's the approach I have always taken with cars and That's all I was looking to offer 72Shortbed12. A $10 fix for a $200 problem.

Again, It is all good. But your RED text is angry. So...So... angry

P.S. Portland swap meet is coming up, neighbor. I try to avoid it. I always spend more than I should.

[72shortbed12]

Thanks for the replies. I have a file sander and feel confident doing it. The motor is out of the truck so it shouldn't be a big deal. I plan on using gaskets no matter what but would like to get a better seal and not risk the manifolds cracking in the future. I agree that taking them to a machine shop would be best but it's not a big enough deal to go through the process on a low mile motor.

[screamin_c10]

Originally Posted by Torrey72

Again, It is all good. But your RED text is angry. So...So... angry

P.S. Portland swap meet is coming up, neighbor. I try to avoid it. I always spend more than I should.

Ha HA... Trucks red so I've just made a habit of it....

You going to the swap meet? I'm gonna see if any spots are still open and drag some junk down there to sell...(gotta fund the next project)

[Torrey72]

Take your time. I only talked about no gasket for test fitting the ramhorn to check your progress. Not for assemble. Also, remember you can take some off the ramhorn if you feel you are removing too much off the head. Good luck
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[screamin_c10]

Originally Posted by 72shortbed12

Thanks for the replies. I have a file sander and feel confident doing it. The motor is out of the truck so it shouldn't be a big deal. I plan on using gaskets no matter what but would like to get a better seal and not risk the manifolds cracking in the future. I agree that taking them to a machine shop would be best but it's not a big enough deal to go through the process on a low mile motor.

Cool, don't let my comments scare ya off. Truth be told, since the motor is out of the truck then I would probably do the same. I thought the engine was still in the truck....

[Torrey72]

If I can get out of work, I'll go to the meet. I had a booth there for years in the early 90's. I would leave with more junk than I brought. It was counter productive as far as cleaning out the shop went.

[screamin_c10]

Originally Posted by Torrey72

If I can get out of work, I'll go to the meet. I had a booth there for years in the early 90's. I would leave with more junk than I brought. It was counter productive as far as cleaning out the shop went.

Yeah, that's kinda my worry too... but I figure I can at least swap some of my junk for someone else's junk and have completely new junk....

As long as I find some truck or Chevelle parts I'm happy...