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Old 11-22-2007, 09:03 PM   #1
crm318
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max hp with 2in ramhorns

i am tired of changing out gaskets with my lontube headers. i was thinking about going back to ramhorns. my engine specs are listed below. how much horsepower can 2in ramhorns support? i also plan or running vortec heads and it will have 350 hp with that setup in the near future. should i stay with the longtubes or will ramhorns flow that much?
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Old 11-22-2007, 09:32 PM   #2
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Re: max hp with 2in ramhorns

youll notice some loss across the board. maybe consider a good set of headers. I know there not cheap, but a quality built header wont give you problems like that. Ive got a set of Sanderson headers on mine. havent blown a gasket in the 4 years theyve been on it....oh did I forget to mention, they dont use any gaskets...at all, just a dab of silicone around each port. they make both long & short tube headers for our trucks with big & small block, they also have performance manifolds
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Old 11-22-2007, 09:36 PM   #3
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Re: max hp with 2in ramhorns

I've never owned a pair, but aren't shorty headers better about not leaking? Just not as much metal dangling down and vibrating around off of the heads.
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Old 11-22-2007, 10:32 PM   #4
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Re: max hp with 2in ramhorns

I think its just a matter of a good set of headers vs. a poorley made set
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Old 11-23-2007, 06:40 AM   #5
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Re: max hp with 2in ramhorns

All you have to do with cheap headers is go over the header to head bolts every now and then.By the time you hear it "tick" it`s usually too late.I check mine when I change the oil.
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Old 11-23-2007, 07:41 AM   #6
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Re: max hp with 2in ramhorns

You know that Corvette rams horn manifolds were 2 1/2" right? You get the best of both worlds, manifolds and flow.
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Old 11-23-2007, 08:19 AM   #7
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Re: max hp with 2in ramhorns

they do flow well....but not like headers
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Old 11-23-2007, 08:24 AM   #8
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Re: max hp with 2in ramhorns

Shorty headers are better about that. I goofed and got long tubes this time and I regret it. Had a set of shortys on the Elky and they were great.

The other thing is the thickness of the flange...mine's 3/16", but the 3/8" [like Hedman Elite Shorty] are much better. These are the ones I will be buying for both trucks down the road.

Very nice big block you have there!
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Old 11-23-2007, 08:34 AM   #9
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Re: max hp with 2in ramhorns

In his truck with a small block, vortec heads, Comp 268 cam and highway gears, the bigger rams horns will be ideal. He'll never turn enough RPM to realize any significant flow advantage of top of the line headers.

With that setup, he'll spend 99 percent of his time below 3000 RPM
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Old 11-23-2007, 09:25 AM   #10
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Re: max hp with 2in ramhorns

yea, i have heard of the 2.5 ramhorns. i would love to have a set, but everywhere i see them, they are super expensive.
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1972 Cheyenne
Chevrolet red and white
357ci, Vortec heads,
GM Performance high rise intake,
Comp 268H .454/.454 218/218 110 LSA
Quadrajet carb, Flowtech headers, 2.25 40 series
HEI, Curve kit, TH 350, 3.07 gears
275/60/15s on 15x8 rallies
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Old 11-23-2007, 01:23 PM   #11
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Re: max hp with 2in ramhorns

personally i would change to copper round port header gaskets. when i first put my headers on my 60 c10 the gaskets were fine until my passenger side went out on me. i haven't had a problem with my coppers yet. a good set will run you about a good $50 though
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Old 11-23-2007, 05:13 PM   #12
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Re: max hp with 2in ramhorns

the problem with my gaskets are that the outsides where the bolt holes go are really thin and they burn. the outside header bolts were covered in carbon. maybe ill give the copper gaskets look.
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1972 Cheyenne
Chevrolet red and white
357ci, Vortec heads,
GM Performance high rise intake,
Comp 268H .454/.454 218/218 110 LSA
Quadrajet carb, Flowtech headers, 2.25 40 series
HEI, Curve kit, TH 350, 3.07 gears
275/60/15s on 15x8 rallies
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Old 11-28-2007, 02:26 PM   #13
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Re: max hp with 2in ramhorns

they are worth the money and the best part is they are re-usable. the only way that you can blow them is if they get melted and if you are melting them then you have other issues you need to look at.
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-07 gmt900 silverado 1500 lt xcab z71, granite blue
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Old 11-28-2007, 03:12 PM   #14
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Re: max hp with 2in ramhorns

I bought mine new for $115 shipped. Is that too expensive? Everywhere else was much more.
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Old 11-28-2007, 03:36 PM   #15
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Re: max hp with 2in ramhorns

It seems that nowdays, 350 Hp is a pretty low HP rating. The factory crate engines with that kind of hp are using 2 inch exhaust manifolds. The ramhorns are in my opinion the best flowing manifolds that GM has ever made. It seems that 2 1/2 inch would work fine, they would be much quieter in the cab and last forever. Probably cheaper than a couple of more sets of headers that you may need before you eventually sell your truck and you get to skip one installation
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Old 11-28-2007, 05:41 PM   #16
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Re: max hp with 2in ramhorns

What year corvettes did the manifolds your talking about come from? I think I want to go that route but see different manifolds for different years...
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Old 11-28-2007, 06:46 PM   #17
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Re: max hp with 2in ramhorns

They are not only used on old Corvettes. Look for 1962-1964 Impala's with a 300 hp 327-they came with the 2-1/2" rams horn manifolds. Also the alternator mounts to the manifold with a bracket from the manifold to the water pump. These engines had the double-hump heads with no accessory holes in the heads.

Good Luck
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Old 11-28-2007, 06:51 PM   #18
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Re: max hp with 2in ramhorns

This is by far the best deal I could find. If you can find a new set cheaper, jump on it.

http://www.performanceexhaustplus.com/

Part number 674-504
Manifold - 1963-62 5.4L (327 CID) Corvette Ram's Horn, LH, 2-1/2" Dia. $57.45

Part number 674-503
Manifold - 1965-62 5.4L (327 CID) Corvette Ram's Horn, RH, 2-1/2" Dia. $57.45

Subtotal : $114.90
Shipping (Free Ground Service): $0.00
Tax : $0.00
Total : $114.90
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Old 11-28-2007, 11:15 PM   #19
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Re: max hp with 2in ramhorns

Go to www.partsamerica.com and look up manifolds for a '65 Corvette with 327 engine. They list them by Motormite and Dorman, for ~$80 each.
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