Rams horn exhaust manifolds

[oldgold70c10]

Originally Posted by Longhorn Man

oddly enough, I have always had more problems with manifilds... and i will be ignoring my own advice and installing header on my longhorn with the new engine... but, in all reality, i would still recomend the manifolds.

Yeah, I love the ramhorn manifolds, but have had more problems with them than with any other style exhaust manifold or headers. But the cause usually ends up tracing back to stuff like bad engine mounts, exhaust system hangers, etc.

[AustinScott]

I ditched my ram horns for some hooker headers & have had 0 yes ZERO problems with leaks or spark plug burning.

As Todd said, I too was having heating issues, cant truly pin it on the exhaust, but I made the change to headers & added a tranny cooler and my heating problems went BY BY. no more over heating when driving down the high way.

I'm also running a modified 327 so the 4000 - 6200 rpm range is quite often a norm for me when I'm enjoying the truck on the weekends!!!

[oldblue1968chevy]

whats the best way to clean these things minus sandblasting?

rusty stock ramhorns? heard of people puttin' em in vinegar or something...

Thanks!!! Glad to hear ramhorns ftw! lol headers are more $ lol

[Robertjust777]

Originally Posted by oldblue1968chevy

whats the best way to clean these things minus sandblasting?

rusty stock ramhorns? heard of people puttin' em in vinegar or something...

looking for a answer i thought powdercoating but not sure if they will hold up cuz of the heat i figure just heat wrap them and its not the best looking but dont look as bad as rust...

[raycow]

Porcelainizing will last forever as long as you don't hit it with anything hard like a tool.

Ray

[mdwilf]

Vinegar is an excellent rust remover - just dunk & wait a few days. Then remove, shake & dunk in baking soda & water to kill the vinegar acid. Dry immeadiately & coat to prevent flash rust.

[oldblue1968chevy]

So where can I get a few gallons of vinegar lol, walmarts?

[71meangreenc10]

I would buy them new, its not worth the energy to work on them and then it cracks or whatever.

Smitty

[oldblue1968chevy]

haha i'll leave em rusty before i buy new ones...Im on a budget here lol..

[mrein3]

Originally Posted by storm9c1

I'm having a 383 stroker built (for torque not for racing). I've done lots of reading on the subject of headers on these trucks and I also have experience with headers in other applications (and most of the time they have been annoying). I've seen dyno results comparing headers to each other and and to ram horns. And have been overloaded with it all. Back in April, I ordered a set of Doug Thorleys since they seem to be the best headers for these trucks from what I researched (ordered from DougThorley.com -- nice discount for board members). But for some reason they are having trouble getting them now and haven't shipped them yet (since April!!!!). I've debated canceling the order and using the stock ram horns. Anyone ever use the rams with a 383 stroker in a non-racing application (towing for example)? I don't want to shoot myself in the foot either way. If it were a stock 350, it's a no brainer (ram horns!). But what about a 383 built for torque?

I'm using stock 4x4 (center dump) ram horns on my 4x4 with a 383. I built the 383 to pull my boat, push a snow plow, pull fish houses around the lake, push/pull boat docks out of the lake, etc.
In my opinion, unless you are having a NASCAR exhaust specialist building you a custom set of exhaust manifolds for YOUR truck, I'd stick with rams horns.
And oh by the way, if you stick with stock rams horns you can order a COMPLETE exhaust kit shipped to your door from Heartthrob exhaust via LMC for around $200.

On one hand:
Flows as good or probably better then headers, no burnt wires, leaks, headaches, $200 to complete the pipes out the back.
On the other hand:
A ton of money, tons of leaks, tons of headaches, custom (expen$ive) exhaust to finish it off.

No brainer.

Originally Posted by oldblue1968chevy

whats the best way to clean these things minus sandblasting?

rusty stock ramhorns? heard of people puttin' em in vinegar or something...

Thanks!!! Glad to hear ramhorns ftw! lol headers are more $ lol

I built my 383 about 6 years ago. I ordered the Eastwoods exhaust manifold coating kit after seeing a guys old Caddie with brand new looking exhaust manifolds at a car show. He said you order the kit, follow the directions, then touch it up when rust starts to show. After 6 years they still look good but could use that touching up he said I would need.

[storm9c1]

Originally Posted by mrein3

I'm using stock 4x4 (center dump) ram horns on my 4x4 with a 383. I built the 383 to pull my boat, push a snow plow, pull fish houses around the lake, push/pull boat docks out of the lake, etc.
In my opinion, unless you are having a NASCAR exhaust specialist building you a custom set of exhaust manifolds for YOUR truck, I'd stick with rams horns.

Man, talking about headers vs ramhorns is like talking to democrats and republicans. People are either polarized one way or the other. I've seen dyno tests comparing these (can't find the link right now), but only on mocked up engine stands and jigs with perfect headers and perfect exhaust conditions. Of course the headers won. But stuffing that setup into these trucks is a whole different story.

I put my truck to work, and I just want the least amount of headaches while maximizing the performance. That's why I ordered the Thorleys, but it seems like it's hard to get them these days. I also don't want massive amounts of heat in the engine compartment, and I have a large PTO hydraulic line running against the frame on the passenger side. So I'm thinking that keeping the ram horns (and maybe having a local machine shop port them) is a better shot. Things happen for a reason and I'm thinking that my bad experience with ordering Thorleys is telling me something...

And oh by the way, if you stick with stock rams horns you can order a COMPLETE exhaust kit shipped to your door from Heartthrob exhaust via LMC for around $200.

Well exhaust isn't a big concern because I will need a custom dual exhaust anyways. If you look at the truck in my avatar, it's not exactly a pickup.

On one hand:
Flows as good or probably better then headers, no burnt wires, leaks, headaches, $200 to complete the pipes out the back.

I see others taking aim at the flow statement there.

I'm not gonna say manifolds of any kind flow better than long tube headers. That's the science of fluid dynamics. What can be said is that some headers (ie: shortys and cheap headers) may not flow any better than ramhorns. The issue is finding a GOOD header that drops in on these trucks without ANY problems.

On the other hand:
A ton of money, tons of leaks, tons of headaches, custom (expen$ive) exhaust to finish it off.

No brainer.

Now those are my biggest concerns -- initial cost, reliability, durability and compatibility without sacrificing performance.

I built my 383 about 6 years ago. I ordered the Eastwoods exhaust manifold coating kit after seeing a guys old Caddie with brand new looking exhaust manifolds at a car show. He said you order the kit, follow the directions, then touch it up when rust starts to show. After 6 years they still look good but could use that touching up he said I would need.

If I get my ramhorns ported, I'll get them coated then. Seems like alot of money to spend on ramhorns, which is what initially brought me to get the Thorleys. Just shoot me now... LOL.

Thanks for the feedback.

[Murphy IRE]

I'm piggy backing on this old thread. I need to replace my broken Rams Horn. The GM casting number is 3797942 (A 63-65 327 Vette). I've gone to several places and no one has that number. They are suggesting 3797901or 3846563. So I can't find how to cross match. The port holes are 1 x 1.
I need a Rams Horn to match up with the 2 1/2 SS exhaust pipe. I'm running a Chevy 400cid. So does any one have:

1) A - 3797942 (drivers side LH) manifold?
2) How to reference these other numbers?
3) Where to buy a 3797942? ( If it references to the other numbers there are a ton of places)


Thanks in advance.

[jaros44sr]

Thoght i bought mine from dorman, ended up cutting off the generator mount, then it doesnt matter if you buy a right or left.....could be wrong on that

[Shaky]

An attempt at the best of both worlds would be opening-up your manifolds. Not sure how much it costs, but you could extrude-hone them (don't look at this if you are eating):

http://www.gethoned.com/process.html

[redmonster]

are ram horns also on I6 250 motors or just small blocks if so i need to replace mine, one of the bolts is cracked along the side and i have a slight leak..;

[kcsa75]

Can these mainifolds be welded or otherwise repaired? I have a pretty good sized crack in one of my and a hairline crack in the other.

[oldblue1968chevy]

i scrapped all my crackedones...

[passthebuck]

Just looked at the Speedway stainless ramshorns - very nice. Two questions:

1) Is there anybody here using them in our trucks?

2) They are center-dump. Will they work with a sb in the stock location?

http://www.speedwaymotors.com/Tru-Ra...301#tabcontent

[1972RedNeck]

I have these on my 383 They even had the right notch for my A/C bracket.

I recently found these results too.

[Murphy IRE]

OK I have found a few things. The Dorman part is 674-502 (2 1/2") and it does have the alt/gen bracket ($70). It might have to be cut off? I found a manifold at Stevens for $149. The dorman appears to have the same tube on the inside. What does that do???? The one from Stevens doesn't have it. Stevens said the hole is for a tube which is for a pre heat on the choke. He said "The holes are there but you won't have any exhaust leak"??? Isn't a hole a hole??? Unless the tube is inserted or the hole filled, won't exhaust leak?

[jaros44sr]

e

Originally Posted by Murphy IRE

OK I have found a few things. The Dorman part is 674-502 (2 1/2") and it does have the alt/gen bracket ($70). It might have to be cut off? I found a manifold at Stevens for $149. The dorman appears to have the same tube on the inside. What does that do???? The one from Stevens doesn't have it. Stevens said the hole is for a tube which is for a pre heat on the choke. He said "The holes are there but you won't have any exhaust leak"??? Isn't a hole a hole??? Unless the tube is inserted or the hole filled, won't exhaust leak?

Just drill and tap for a 3/8" NPT and plug after you knock out the tube. Use a 1/8" cut off wheel on a angle grinder to clean up the alt. mount...thought Dorman's were 49.00 on that site up top

CORRECT on the hot air for the choke
Actually,now that think about it, you don't even have to drill it

[bcutt]

Are these the Ram horn manifolds you guys are talking about?

[Murphy IRE]

Yep! What size are the intake (square or round) and exhaust ports?

[bcutt]

Not sure, never removed them from the engine. It's funny cause my Dad has been telling me "them are good manifolds, you want to keep them", my response to that is, heck no I'm getting rid of them and getting some headers first chance I get Now I am thinking maybe I should take his advice...LOL

[406 Q-ship]

I know this is an old thread but here is my take on the manifold/header debate. If your looking for 100% no mainetance system then manifolds are the only answer, but if you have a engine of any HP then you can be leaving as much as 50 hp on the table. Stock engines are not loosing with manifolds unless you have an 370 HP LT-1. Ram horns are the best of the SBC manifold hands down for performance. BTW the later log manifolds fit the 67-72 frame just fine, mine has them. Now if your willing to spend a little money along with sometime during oil changes and tune ups, then headers are not that big of a hassle. If the engine is over 350 CID and the cam has more than 220° duration at .050 along with everything to support an engine of this performance level then headers will have a gain most of the RPM range (not just above 3000). In a truck that actually works as a truck (tows and haul heavy loads) I would keep the ram horns (I also would build a 400 SBC that was under 220° and 9.0 compression) but a set of small headers would work. Headers will radiate heat faster and the tune needs to adjusted to suit the headers (this is why most complain about the header making the engine run hot). NEVER wrap the headers unless you like replacing headers alot, it will embridle the metal and they WILL crack (I know this cause I have worked with header company on warrentys). I have a 406 SBC in a Monte Carlo that was dynoed with ram horns (2 1/2" Corvettes ported) that put out 370 HP/420 lbs ft but after the engine was in the car the cast iron logs were tossed in favor of 1 3/4" primary 30" long 3" collector Hookers Super Comps. The car used to run 14.10 at 99 MPH, after the headers (along with a retune) Monte went 13.50 @ 104MPH (this 406 is out of steam by 5500 RPM) and the driveability is so much better with the headers. It is like anything else you need to descide how your going to use the vehicle and how much work your willing to do to achieve a level of performance.