rect or oval port?
Thread Starter
Pro
Joined: Nov 2004
Posts: 575
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From: Nice Lake Ontario
rect or oval port?
I have an oppertunity at a set of 69 oval port cyclinder heads for a future BB swap in my car 
Should I pick them up or is a set of rec port heads that much better even if they are usually larger cc heads??
Whats the cost of valve seat hardening if they haven't been done!
Talk to me about heads, I'm just not in the know
I'm not after a big HP performance machine just a nice sporty driver, say 350-400hp with lots of torque
Thanks for all opinions
Should I pick them up or is a set of rec port heads that much better even if they are usually larger cc heads??
Whats the cost of valve seat hardening if they haven't been done!
Talk to me about heads, I'm just not in the know
I'm not after a big HP performance machine just a nice sporty driver, say 350-400hp
with lots of torque Thanks for all opinions
Safety Car
Joined: Jul 2002
Posts: 3,770
Likes: 3
From: St Louis MO
Ovals will be fine for what you want. The square ports are more "racy" and more $. I've had 2 local people call me about selling me their complete, assembled 990s...one wanted $900, the other $1100.
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
Originally Posted by Brettmc
Ovals will be fine for what you want.
Originally Posted by Brettmc
The square ports are more "racy" and more $. I've had 2 local people call me about selling me their complete, assembled 990s...one wanted $900, the other $1100.
Instructor
Joined: Dec 2004
Posts: 171
Likes: 0
From: Ontario
Oval heads
Hello
If you want bottom end torque and are not buzzing the motor, then go with the oval port heads
The heads should work in conjunction with your engine combination and if you want bottom end grunt, the oval heads will be the better choice.
Tom
If you want bottom end torque and are not buzzing the motor, then go with the oval port heads
The heads should work in conjunction with your engine combination and if you want bottom end grunt, the oval heads will be the better choice.
Tom
Team Owner
Joined: Jul 2004
Posts: 40,275
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From: Redondo Beach, California
I drove my rectangular large port heads on the street with no problem. This was an L88 clone with a Richmond 5 speed and a 3.08:1 rear end. My opinion is that if you're going with a big block you just might as well go for the max. With the rectangular intake ports, each cylinder intake is larger than most cars complete exhaust pipe!!
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Square port heads are really only effective where a hydraulic cam stops, just below 6 grand and up. However they do work ok. But as other posts indicate, they are worth much more. Might as well get a good solid lifter cam from a 435 HP engine and really make some black top ripping power. 
Race Director
Joined: Feb 1999
Posts: 16,978
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From: In Dreams There Is Truth Ohio
If you are going to use the factory oval port heads, you will spend more $$$$ in port work than if you were to buy square port heads. However, if you are going to purchase new heads from Edelbroch, the price should be comparable. If that's the case, I would choose the square port heads....sq. ports is all I know, never had a ovals on my BB. And speaking of grunt....I have more than enough at low RPM.
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Race Director
Joined: Dec 1999
Posts: 11,092
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From: Sierra Foothills CA
Originally Posted by sxr6
I have an oppertunity at a set of 69 oval port cyclinder heads for a future BB swap in my car
Should I pick them up or is a set of rec port heads that much better even if they are usually larger cc heads??
Whats the cost of valve seat hardening if they haven't been done!
Talk to me about heads, I'm just not in the know
I'm not after a big HP performance machine just a nice sporty driver, say 350-400hp with lots of torque
Thanks for all opinions
Should I pick them up or is a set of rec port heads that much better even if they are usually larger cc heads??
Whats the cost of valve seat hardening if they haven't been done!
Talk to me about heads, I'm just not in the know
I'm not after a big HP performance machine just a nice sporty driver, say 350-400hp
with lots of torque Thanks for all opinions
Instructor
Joined: Dec 2002
Posts: 222
Likes: 0
From: Leander TX
I have a pair of 840 rec port heads that came with the 427 I bought. It cost me just over $900 to get the seats and guides done for unleaded gas, which also included new stainless valves + springs to handle the extra lift of the comp cams magnum solid lifter cam I'm going with. I figure that I could always get the money out of them if decide to go with more modern heads at some point.
Thread Starter
Pro
Joined: Nov 2004
Posts: 575
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From: Nice Lake Ontario
Thanks for all replys!
And a special thanks to henny496 for the additional info
It's been since the mid 70s since I've been into or worked on these old girls, it's comein back just slowly 
I think these heads will be fine, as long as they are in good enough shape, I'll pick them up
And a special thanks to henny496 for the additional info
It's been since the mid 70s since I've been into or worked on these old girls, it's comein back
just slowly I think these heads will be fine, as long as they are in good enough shape, I'll pick them up
Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
Regardless of what head you choose you do NOT need to worry about the exhaust seats. Unleaded gas will not harm the old head seats. Don't waste your money. I do recommend good guides be installed in the head at the time of the valve job. The only need for hardened exhuast seats is if you are towing with the vehicle.
The oval ports will work fine and up to 6000 will outdo the rectangular heads.
The oval ports will work fine and up to 6000 will outdo the rectangular heads.
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Those 69 heads you are talking about will not flow as well as a later set of open chamber oval port heads. The early heads ahve a closed chamber that really kills airflow over the later versions. I have a set of the 291 oval ports (72 LS5 heads) that Lingenfelter really liked in his big block build-up series in Hot Rod Magazine. They are anyone's for $175 shipping included and I can provide 2.19/1.88 s.stl valves for another $85 plus springs, retainers, shop labor for anyone in the market for a set. Guaranteed to be crack free and in excellent shape with factory induction hardened exhaust seats already there.
Safety Car
Joined: Jul 2002
Posts: 3,770
Likes: 3
From: St Louis MO
Originally Posted by Solid LT1
Those 69 heads you are talking about will not flow as well as a later set of open chamber oval port heads. The early heads ahve a closed chamber that really kills airflow over the later versions. I have a set of the 291 oval ports (72 LS5 heads) that Lingenfelter really liked in his big block build-up series in Hot Rod Magazine. They are anyone's for $175 shipping included and I can provide 2.19/1.88 s.stl valves for another $85 plus springs, retainers, shop labor for anyone in the market for a set. Guaranteed to be crack free and in excellent shape with factory induction hardened exhaust seats already there.
3964291....69-72...rect..CLOSED..396, 402, 427, 454, 109cc chamber, Large or small hex spark plugs used, crate motor usage in years after 1970.
Can you verify?
Brett
Race Director
Joined: Feb 1999
Posts: 16,978
Likes: 7
From: In Dreams There Is Truth Ohio
yep...291 is a closed chamber, sq. port head with the narrow, tapered plug...last one produced by GM. Identical to the 66-69 heads, except for the spark plug.
Maybe he meant a 241 head
Maybe he meant a 241 head
Last edited by GDaina; Aug 26, 2005 at 11:20 AM.
Safety Car
Joined: Jul 2002
Posts: 3,770
Likes: 3
From: St Louis MO
SXR6 - Since this is your thread, I shouldn't have jumped in and said I would buy those heads without giving you first crack at them. Sooooo, go ahead and set up your deal if you want them. BUT I got game. If they are large port, open chambered oval ports I would like a chance at them if you don't want em. Sorry bout dat...
Brett
Brett
Instructor
Joined: Oct 2004
Posts: 118
Likes: 1
I dont think your lucky enough to find 291 heads for that price, sounds like they are either 292 or 241 going by the year and the application he has listed, either way that is still a pretty good deal, I have a set of the 292 on a motor Im building for my 70 camaro, you can make over 400 hp with the heads bone stock, if you want to make over 500hp you can install larger valves and do some porting in the bowl under the valves. 3999241 1972 402 240, 300, 330 LS-3
454 Open 365 LS-5 113.0cc
6272292 1971 402 240, LS-3
454 Open 270, LS-5
454 Open 365 LS-5 113.0cc
6272292 1971 402 240, LS-3
454 Open 270, LS-5
Thread Starter
Pro
Joined: Nov 2004
Posts: 575
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From: Nice Lake Ontario
"SXR6 - Since this is your thread, I shouldn't have jumped in and said I would buy those heads without giving you first crack at them. "
Ahh Brettmc.... a man of integrity
I appreciate the gesture but unless Solid LT1 is in Kanada they are yours
If Solid LT1 is in Kanada however, Send me your address a money orders is on the way
Appreciate the help guys
Ahh Brettmc.... a man of integrity
I appreciate the gesture but unless Solid LT1 is in Kanada they are yours
If Solid LT1 is in Kanada however, Send me your address a money orders is on the way
Appreciate the help guys