Raised Exhaust Ports?
Thread Starter
Safety Car
Joined: Aug 2000
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From: Clymer PA
Raised Exhaust Ports?
I have Hooker Header Side Pipes for my big block. They are 2 1/8" header primaries. I know Steve Straus went through a lot of trouble having his headers modified for use with his Canfield heads with raised exhaust ports.
Would I run into issues with my headers if I were to go with say Merlin heads with raised exhaust ports? It seems like almost every aftermarket head has raised exhaust ports so my choices are kinda limited.
Any help is greatly appreciated!
Would I run into issues with my headers if I were to go with say Merlin heads with raised exhaust ports? It seems like almost every aftermarket head has raised exhaust ports so my choices are kinda limited.
Any help is greatly appreciated!
Race Director
Joined: Dec 1999
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From: Forked River NJ
Re: Raised Exhaust Ports? (bence13_33)
Can't help you here but it seems every time you replace one part for more HP 3 more parts need to be modified to make everything fit. Good luck with this
Race Director
Joined: Dec 1999
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From: Sierra Foothills CA
Re: Raised Exhaust Ports? (bence13_33)
bence,
I've looked at that issue too. In my case it just isn't worth the extra hassle & expense. It's hard enough to find headers that fit our cars well, let alone adding the raised port issue. However, if you feel that you have enough to gain by doing so, go for it. There's always somebody that can make custom headers. Headers by Ed is a name that I've heard good things about- just be prepared to crack open your wallet. :cheers:
I've looked at that issue too. In my case it just isn't worth the extra hassle & expense. It's hard enough to find headers that fit our cars well, let alone adding the raised port issue. However, if you feel that you have enough to gain by doing so, go for it. There's always somebody that can make custom headers. Headers by Ed is a name that I've heard good things about- just be prepared to crack open your wallet. :cheers:
Burning Brakes
Joined: Aug 2001
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From: Bay City MI.
Re: Raised Exhaust Ports? (bence13_33)
Bence 13-33, I went through some trouble with my Merlin rectangular port heads because of the raised port design. The brackets for alternator and power steering pump had to be modified, and as you know the headers were slightly off too. My Sanderson headers actually are designed for the 502 motor with raised port heads, but the primary tubes are only 1 7\8. Even though it was a pain in the but, the big Merlin heads are awesome! Now that I put on the 850dp carb my motor spins to 6k rpm with ease. Good luck... Tom
Safety Car
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From: Allen TX
Re: Raised Exhaust Ports? (bence13_33)
Can't help you except to confirm the research you've done. My side-exit Hookers will not allow _any_ raised port on the exhaust...not without significant modification.
So, yes, this definitely limits us as to what heads we can run. If I swap heads, I'm probably going to go with some Edelbrocks, but my HP goals may be a lot less than yours. I'm shooting for 500-550hp using a hyd. roller cam and low-rise intake. The Edels (and other stock exhaust port locale heads) should handle this.
So, yes, this definitely limits us as to what heads we can run. If I swap heads, I'm probably going to go with some Edelbrocks, but my HP goals may be a lot less than yours. I'm shooting for 500-550hp using a hyd. roller cam and low-rise intake. The Edels (and other stock exhaust port locale heads) should handle this.
Le Mans Master
Joined: Mar 2001
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From: Watkinsville, GA and Glen Cove, NY
Re: Raised Exhaust Ports? (bence13_33)
Bence, I really fought this decision myself before deciding to go with the Brodix head for my 502. I think every car is different. I really had to bash my drivers side header to get it to fit with the standard head but the passenger side fit perfect but I know with the new head based on the visible clearance it won't fit. My solution will probably be to sell the Hookers and go to a set of Stahl's made specifically for the raised port head. I just don't want to leave any horsepower potential on the table. Now having said that, the Merlins only have a 1/4 inch raised port and the Dart's I believe are .3 so they could fit your car. One advantage of the Stahl's is equal length and shorter primaries so the bundle of pipes does not come out from under the car like the Hooker. Not sure which look I prefer but I guess they would build them any way you like. Now I haave another issue as I need a new crank so I will build a 533 so I am trying to sell my brand new in box Brodix BB+2's and get a bigger head. Bill.
Thread Starter
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From: Clymer PA
Re: Raised Exhaust Ports? (69ttop502)
Tom:
Do you think it would be possible with my 2 1/8" primaries to use the Merlin heads without modifying them?
Bill:
Do you think the Merlins would fit without modifying the headers? I really don't want to have to mess around with modifying the headers. I most likely will end up going with a set of "990" heads with lots of port work, 325cc runners and 2.25/1.88 valves to avoid the header issue. The 8-71 blower motor will most likely have more power than I'll ever be able to put to the ground anyhow. But if at all possible I would like to go with Merlin heads without modifying the headers.
Do you think it would be possible with my 2 1/8" primaries to use the Merlin heads without modifying them?
Bill:
Merlins only have a 1/4 inch raised port and the Dart's I believe are .3 so they could fit your car
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From: Charles Town WV
Re: Raised Exhaust Ports? (bence13_33)
Would I run into issues with my headers if I were to go with say Merlin heads with raised exhaust ports? It seems like almost every aftermarket head has raised exhaust ports so my choices are kinda limited.
Any help is greatly appreciated!
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Pro
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From: North Port, FL
Re: Raised Exhaust Ports? (bence13_33)
You might take a look at Edelbrock Victor Jr. CNC rectangular port heads. They were the only decent flowing head I could find with exhaust ports in the stock location.
Thread Starter
Safety Car
Joined: Aug 2000
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From: Clymer PA
Re: Raised Exhaust Ports? (ZL1powr)
ZL1powr:
The Edelbrock Victor Jr.'s with CNC porting have the stock exhaust port location? If so, I think I'd rather go that route than trying to get a set of "990" heads to flow. Are those the heads you are running?
*EDIT*
I just put the Victor Jr. heads into my engine combo on DD2000....MAN what difference! If these heads do indeed have the stock exhaust port location, I am definitely going with them.
[Modified by bence13_33, 7:55 PM 2/9/2003]
The Edelbrock Victor Jr.'s with CNC porting have the stock exhaust port location? If so, I think I'd rather go that route than trying to get a set of "990" heads to flow. Are those the heads you are running?
*EDIT*
I just put the Victor Jr. heads into my engine combo on DD2000....MAN what difference! If these heads do indeed have the stock exhaust port location, I am definitely going with them.
[Modified by bence13_33, 7:55 PM 2/9/2003]
Pro
Joined: Jul 2002
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From: North Port, FL
Re: Raised Exhaust Ports? (bence13_33)
bence13_33
The Victor jr CNC's definitly have the exhaust ports in the stock location. I have been real pleased with mine. No problems at all with mounting the Hooker header side pipes.
ZL1powr:
The Edelbrock Victor Jr.'s with CNC porting have the stock exhaust port location? If so, I think I'd rather go that route than trying to get a set of "990" heads to flow. Are those the heads you are running?
*EDIT*
I just put the Victor Jr. heads into my engine combo on DD2000....MAN what difference! If these heads do indeed have the stock exhaust port location, I am definitely going with them.
[Modified by bence13_33, 7:55 PM 2/9/2003]
The Edelbrock Victor Jr.'s with CNC porting have the stock exhaust port location? If so, I think I'd rather go that route than trying to get a set of "990" heads to flow. Are those the heads you are running?
*EDIT*
I just put the Victor Jr. heads into my engine combo on DD2000....MAN what difference! If these heads do indeed have the stock exhaust port location, I am definitely going with them.
[Modified by bence13_33, 7:55 PM 2/9/2003]
Burning Brakes
Joined: Aug 2001
Posts: 1,002
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From: Bay City MI.
Re: Raised Exhaust Ports? (bence13_33)
Bence, If you are interested in the Merlins, check them out on the web, World products, here in Michigan. My friend who built my motor last year just built a very strong 540 with a set of Merlin rectangular port heads, with hydraulic roller cam and big Demon carb. Its going in a Chevelle race car, the owner of the car has been in the drag racing scene for over 35 years, I think his choice says something? After all of that, as cool as the Merlins are, and I love mine, the raised port design does make life interesting, they are 3\4 of inch over stock not 1\4 too. You might be in for a lot of headaches so it would be easier to stay with the stock type heads and work with them. But hey who said making big HP would be easy?
Le Mans Master
Joined: Mar 2001
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From: Watkinsville, GA and Glen Cove, NY
Re: Raised Exhaust Ports? (467-Ratman)
Bence, call World Castings and ask for Corvette Mike. He will give you some ideas. I called a few months ago and at the time all they had available was the 350cc intake port head. He is also the one that told me that that particular head only had the ports raised 1/4 inch. This was an aluminum head. The 350 is too big for my needs but he is a good guy to talk to as he knows Corvettes. Sorry I don't have the phone number handy but I believe it was on the website but when I called the number it was NY not Michigan. Bill.
