Ram Horn Exhaust Question

[TonyJohnson]

The Dorman 2.5" ram horns work fine on the Vortec heads, with the exception of a little grinding on the top square casting lugs so the centerbolt valve covers will fit properly. The straight down exit works fine on my 4 wheel drive Blazer.

[mr_earnhardt1]

Any thoughts on the "limit" of the ram horn manifolds compaired to headers as far as engine mods and performance? Larger cams and such?

[Lee H]

Originally Posted by woodfork1

Which after market ram horns do you recomend for SBC 350 to go into my 71 C10? Straight dump or should I get the curved dumps?

C10 with the engine in the standard location need the curved, C10 and Ks in the 4x4 location can use the straights. I would look in the classifieds for OEM manifolds before going after market unless you need the 2.5 inch versions. Probably Dorman if after market.

[Lee H]

The rams horn exhaust manifolds were designed by Zora Arkus-Duntov in the early 50s for use on the corvette. They will fit all G1 & 2 SBC heads. They were later adapted for several other platforms. Most were 2 inch with 2.5 inch used on corvette 350, 365, and 375 HP solid lifter 327ci engines in the mid to late 60s. Like all GM performance engines of the late 60s and early 70s these HP ratings were very conservative. While headers typically add about 20-25 Horses to a small block, switching from rams horns will only add about half that. My blue printed 30-30 solid lifter cammed 365hp 327 only gained 7 ponies on an engine dyno going from rams horns to headers.

Duntov was the father of GM racing and was the chief designer from mid 50's through the hay days of the 60s and early 70s. In the 40s his company pioneered the ford V8 flathead aluminum head design that later turned into Offenhauser. As a designer and driver he won several class divisions at Le Mans in the early 50s driving a porsche. Soon after he joined GM and laid the foundation and strategy that Chevrolet has used ever since to create the most successful performance parts programs in the industry. In the process, he would change the Corvette from mundane into a formidable sports car that challenged Porsche, Ferrari, Maserati, Mercedes-Benz, and won.

[mgchevyparts]

Originally Posted by Lee H

C10 with the engine in the standard location need the curved, C10 and Ks in the 4x4 location can use the straights. I would look in the classifieds for OEM manifolds before going after market unless you need the 2.5 inch versions. Probably Dorman if after market.

Looking at my 71 they look like they may fit, the driver side might be close to the engine mount. Harpie, a few replies back says he has them on his 71 C10 2wd without an issue.

[slikside]

Originally Posted by Lee H

The rams horn exhaust manifolds were designed by Zora Arkus-Duntov in the early 50s for use on the corvette. They will fit all G1 & 2 SBC heads. They were later adapted for several other platforms. Most were 2 inch with 2.5 inch used on corvette 350, 365, and 375 HP solid lifter 327ci engines in the mid to late 60s. Like all GM performance engines of the late 60s and early 70s these HP ratings were very conservative. While headers typically add about 20-25 Horses to a small block, switching from rams horns will only add about half that. My blue printed 30-30 solid lifter cammed 365hp 327 only gained 7 ponies on an engine dyno going from rams horns to headers.

Duntov was the father of GM racing and was the chief designer from mid 50's through the hay days of the 60s and early 70s. In the 40s his company pioneered the ford V8 flathead aluminum head design that later turned into Offenhauser. As a designer and driver he won several class divisions at Le Mans in the early 50s driving a porsche. Soon after he joined GM and laid the foundation and strategy that Chevrolet has used ever since to create the most successful performance parts programs in the industry. In the process, he would change the Corvette from mundane into a formidable sports car that challenged Porsche, Ferrari, Maserati, Mercedes-Benz, and won.

Cool history lesson. Brings more "life" into these parts we talk about so much. Thanks for posting.

[Stu Pidd]

And here I've been thinking I'd toss out the rams horn manifolds on my truck and install headers before long.
Had no idea they were from the brilliant mind of Zora Arkus-Duntov

Time for a re-think......

[Already Gone]

I started this thread and really like the way threads can weave and bob and still keep to the original theme. Thats one of the things that makes this site super.
Posted via Mobile Device

[samkost]

Once again, Great site!

I decided to remove my Hedman Headers and install the original Ramshorns on my 72' C-10 1/2 ton.
I have read other forum discussions about not using gaskets or Grade 8 bolts.
I don't have the bolts for mounting and need to get the correct hardware.
Can someone please tell me if there is a specific manifold bolt kit you would recommend or lets say NAPA parts have the correct length bolts, washers and copper nuts for installing?

Any advice and feedback would be appreciated.

Thanks, Sam

[jocko]

I've had ram's horns and headers. Realistically, headers are only a horsepower maker in the higher rpm range, but they may help a little on the lower end of the range. They should be considered for an engine upgrade if the intake (carb, valves, cam (especially) are non-stock, performance oriented. Not much point to them on a bone stock engine as ram's horns are pretty efficient. Used to think everything needed headers, but got kinda tired of the extra noise - prefer stock for the most part now. And they don't eek as much heat into the eng compartment either. My 2c! And thanks for the cool info Lee.

[g mcmaine]

Did all the small block trucks use the heat riser?Is there any way to delete it?
Thanks.

[leftybass209]

Originally Posted by g mcmaine

Did all the small block trucks use the heat riser?Is there any way to delete it?
Thanks.

No, there are many small block trucks without the heat riser.

[michael bustamante]

I picked up a nice setnof ramhorns angled off a 69 el camino with a 307. It has the emission rods sticking out of them. Can they be easily removed and then plugged?

[mechanicalman]

Originally Posted by woodfork1

Can Ram horns fit on 96 -20 vortec heads?

Yes

However, I prefer LT-1 iron manifolds.

[mechanicalman]

Originally Posted by Already Gone

Do the ram horn exhaust manifolds work like headers and are they factory? Were they available for big blocks?
Posted via Mobile Device

Check out these bad boys

http://www.speedwaymotors.com/Tru-Ra...Iron,3823.html

[TonyJohnson]

check this thread: http://67-72chevytrucks.com/vboard/s...d.php?t=404828

[mechanicalman]

Originally Posted by TonyJohnson

check this thread: http://67-72chevytrucks.com/vboard/s...d.php?t=404828

Used ram's horns on my 72 since 83, when I was still a bachelor. I painted them in my self-cleaning oven and they stayed white until I removed them last year and installed hooker headers. Best mod I ever made performance wise (feels like 40 extra HP on 2 1/2" existing single exhaust using flowmaster Y adaptor and flowmaster 50 that was always on there), and no trouble getting them to seal using MLS gaskets on the heads and copper on the collector. Hooker the only header manufacturer I know that sells an a/c bracket for the 67-72 C10 for the passenger side A6 compressor that fits.

I've tried cheap headers before and they are a waste of time. If I went back to cast iron I'd want either the LT-1 manifolds or the Speedway ram's horns. I'm convinced that the factory ram's horns are likely better in dual exhaust configuration, the factory Y pipe is poorly designed, and even worse if the reversion cones are gone. I'm only speaking of the 2" outlet that angles out I've never used the Corvette style with 2 1/2" outlets that go straight down; I've heard they are better. I'm installing a SWB frame soon, and will likely upgrade to 3" pipe.

What I've done, and my experiences.

Have fun and be safe.