AMC race cylinder heads

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Holeshot

AMC heads

Post by Holeshot »

850 HP with Indy ported heads thru 1-4 bbl. isn't enough?

I don't think you'll find any better heads for AMC than the fully ported Indy race head.
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Post by Ken_Parkman »

How fast do you want to go? While the Indy -1 is still a true wedge head with a low port they do seem to work well - as good as any. To be honest I'm shocked how well they do work. I got a set on a friends very well thought out and executed car running 170 mph normaly aspirated at 2700 lbs. No matter how you cut it that's pretty good power out of a wedge head.
Holeshot

AMC race heads

Post by Holeshot »

That is VERY good, especially when you consider it is on an engine that was designed forty some years ago and out of production for decades!

The iron dog-leg heads are also very good when fully ported, capable of very good HP but at a step lower than the Indy race heads. 600 HP is fairly easy and 500 HP is a breeze with nothing but common hotrodding techniques. As good or better than most ported stock head castings, with a forty plus year old design! AMC did their homework on the '70 heads and their TransAm championships and some big Prostock wins proved it, causing the big three to retire from T/A competiion in embarassment. Beaten by your grandpa's Rambler! Boo Hoo Hoo
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Post by steve25 »

The AMC Edelbrock head should be able to hit 320 CFM@ 28" on the intake side with a bigger valve. Thta should make a easy 650 hp for you!
Holeshot

AMC race heads

Post by Holeshot »

I've been in contact with Edelbrock. They said that you can't fit any bigger valves in their head. Their head is designed to compliment their Performer intake and cam, putting it all at a VERY mild (for AMC) stock replacement performance level. Just saving a few pounds, whoopie. I now have 2.08 x 1.74s in my ported 291Cs that made 518 HP @ 6500 (on the traveling HotRod Power Tour chassis dyno) with a single Holley and stock valves. Should have picked up another 20 or 30 HP I'm hoping. (That's what Dyno 2000 says, anyway)
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Post by shawn »

The biggest problem with all of the "stock" type AMC heads is the pushrod pinch area. You can make those Edelbrock heads move a ton of air, but it puts your air speed into ballistic missle range. Yes, you can put a larger valve in them, but again, without opening up that pushrod area, your just waisting your time.
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Re: AMC race cylinder heads

Post by Jeff Lee »

Well after waiting for 13 years....how about this for an AMC V-8? Collaboration by Ken Parkman and Kevin Fontenot!

Image

Image

See the thread here:
https://theamcforum.com/forum/ultimate- ... 09913.html
NHRA SS/G
1970 AMC AMX - 390 4-speed
Advanced Clutches - Red Line Racing Cams
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Re: AMC race cylinder heads

Post by mag2555 »

What level of power are you looking for and how much added work are willing to put into any head?

In terms of avaible heads the Edelbrock if you install interlocking seats you can get that 2.02" Intake up to 2.19".

Heavy porting work done then on the heads should then net you 340 cfm@ 28" and then without going to a full on race compression of 14 to 1 still get you well into the over 725 hp range.
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Post by Walter R. Malik »

phoenix wrote: Thu Nov 02, 2006 9:00 pm Can BB Chrysler heads be modified to fit AMC blocks? The bore spacing is close. 4.75 (AMC), 4.8 (Mopar). I know Fred Brewer was doing this with his AMC/BB Mopar heads. Not sure if they were different castings or modified cores?
A Buick big block engine is exactly 4.75" bore center. Raised runner T/A heads are available.

Edelbrock also offers an AMC head which works well when moving the pushrod holes over.
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Re: AMC race heads

Post by Walter R. Malik »

Holeshot wrote: Mon Dec 08, 2008 9:54 am I've been in contact with Edelbrock. They said that you can't fit any bigger valves in their head. Their head is designed to compliment their Performer intake and cam, putting it all at a VERY mild (for AMC) stock replacement performance level. Just saving a few pounds, whoopie. I now have 2.08 x 1.74s in my ported 291Cs that made 518 HP @ 6500 (on the traveling HotRod Power Tour chassis dyno) with a single Holley and stock valves. Should have picked up another 20 or 30 HP I'm hoping. (That's what Dyno 2000 says, anyway)
You can buy a "raw" Edelbrock head and install bigger intake valves with a smaller exhaust valve.
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Re: AMC race cylinder heads

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