Ram Horn Exhaust Manifold

[DD1]

Originally Posted by vince1

Just curious, what would be the reason to change them unless they are cracked or something?

Just when I needed them a set came up on kijiji for forty bucks and for the old farm truck they work just fine. My truck will always be a beater.

If they work, keep them. No reason to change that I can think of.

[Tom]

You don't change manifolds unless you are changing the style or the manifold failed. Ramhorns came in both 2" and 2.5" collector versions and lots of people like upgrading to the 2.5" versions.

[kenn]

Hello, I am looking for a set of 2.5 manifolds. The ones on my 72 cracked (don't know the #)and I replaced them with Dorman's that have the pipe plug hole in them. I would like to get the ones without that hole but the only ones I can find are strait down and one of mine is angled towards the back. I don't really want to change my exhaust to fit the strait ones. Do they make these now that look like stock ones and where could I get a pair. Thanks K.E.N.

[The Rocknrod]

Originally Posted by kenn

Hello, I am looking for a set of 2.5 manifolds. The ones on my 72 cracked (don't know the #)and I replaced them with Dorman's that have the pipe plug hole in them. I would like to get the ones without that hole but the only ones I can find are strait down and one of mine is angled towards the back. I don't really want to change my exhaust to fit the strait ones. Do they make these now that look like stock ones and where could I get a pair. Thanks K.E.N.

Jegs - https://www.jegs.com/i/JEGS+Performa...BoCaMcQAvD_BwE
Summit - https://www.summitracing.com/parts/s...hoCQCwQAvD_BwE
Speedway - https://www.speedwaymotors.com/Smoot...Raw,94194.html
Even eBay - https://www.ebay.com/itm/NEW-SMALL-B...4AAOSwYEBcfxd2

[mattfranklin]

My shorty headers block the dipstick from working properly. So I'm looking, and these 2.5" newer ones are sure a lot cheaper than the original 'vette parts.

I want to go with more of a stock-ish look, so these are great for me. My question, though, is are these compatible with the stock-style heat shields that protect the plug boots?

[kenn]

Thanks but I have looked at those and they are strait dump I need the angled dump.

[The Rocknrod]

Originally Posted by kenn

Thanks but I have looked at those and they are strait dump I need the angled dump.

I've never seen an angled dump cast iron manifold at 2.5". If you find a set let me know I will buy it if you dont.

[AcampoDave]

Originally Posted by mattfranklin

My shorty headers block the dipstick from working properly. So I'm looking, and these 2.5" newer ones are sure a lot cheaper than the original 'vette parts.

I want to with more of a stock-ish look, so these are great for me. My question, though, is are these compatible with the stock-style heat shields that protect the plug boots?

Pobably, Corvettes did come with heat shields.

[Bigdav160]

Originally Posted by AcampoDave

Pobably, Corvettes did come with heat shields.

Extensive ignition shielding

[kenn]

Thanks rod that makes my search easer, I have had the Dormans on for a little while so I could be mistaken but I thought they were 2.5s.

[Tom]

2.5's only came strait dump from the factory.

[External]

My manifolds leak now. 48 years old heated and reheated meatal.
I pulled the engine, rebuilt it, put it back in. I didnt think at the time they might warp.
I tried basic gaskets. Then the thick ones.. still leak. Might be cracked somewhere. I dont know. I WANT dual exhaust, so new pipes and mufflers. I just figured I'd replace the manifolds since I was there. I have the problem we all get from time to time. I purchased the black ceramic coated ones. Hoping they wont rust any time soon.

[The Rocknrod]

Originally Posted by External

My manifolds leak now. 48 years old heated and reheated meatal.
I pulled the engine, rebuilt it, put it back in. I didnt think at the time they might warp.
I tried basic gaskets. Then the thick ones.. still leak. Might be cracked somewhere. I dont know. I WANT dual exhaust, so new pipes and mufflers. I just figured I'd replace the manifolds since I was there. I have the problem we all get from time to time. I purchased the black ceramic coated ones. Hoping they wont rust any time soon.

Those are nice, I like the coating color.

[External]

Hate to admit, but I got then from jegs.

[mattfranklin]

Wow, those are some serious shields.
Where did you get them?
Part numbers or links?
Thanks!

Originally Posted by Bigdav160

Extensive ignition shielding

[The Rocknrod]

Here are some modified manifolds to consider:
https://www.castheads.com/exhaust-ma...ust-manifolds/

[AcampoDave]

Originally Posted by The Rocknrod

Here are some modified manifolds to consider:
https://www.castheads.com/exhaust-ma...ust-manifolds/

I kind of did that to my own manifolds. I bought the wand extension for my Dremmel and gave a pair of stock 2" rams a port n' polish.

What he said about imported ones also rang true in my case. At one time I had purchased a pair of Chinese 2.5 straight dumps and (after they cracked), I compared them to the OEM two inchers I was replacing them with. I noticed the port openings on the imports were clearly smaller and figured they likely occluded the head offsetting any gains provided by the larger outlet. Ultimately, I used the OEM 2" ones (that I took the Dremmel to) and mated them to a mandrel bent Summit pipe kit, added performance mufflers, and I'm still happy.

[mattfranklin]

I just ordered the Dorman 674-504 for the driver side on my '70 with the 350. It's to replace a shorty header that the truck came with. That shorty wouldn't let the dipstick tube fit properly and tended to burn the plug wires. I'll let you guys know how it goes.

Originally Posted by fleetsidelarry

I agree with 72Freak, there's just no need for headers on mild build, daily drivers (like mine for instance). If you're going to open them up occasionally for a blast down the track, then that's a different story. I run the 2.5 rams horns. started off with an e-bay set of corvettes at about $225/set. exhaust guy broke a tab on one of the flanges and that manifold eventually cracked a couple of years later. replaced it with an after market version, basically like the Speedway one for basically that price ($80-90 ea)

p.s.: 2.5s into a 3" would be an excellent way to run, thought about that myself.

p.p.s. buy this: http://www.summitracing.com/parts/rnb-674-504/overview/ $47.97
and the matching one for the other side: http://www.summitracing.com/parts/rnb-674-503/overview/ $51.97

and you should make the $99 free shipping cutoff