TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > AMC V8 Engine Repair and Modifications
  New Posts New Posts RSS Feed - 327 Question: Will heads support 300 HP?
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

327 Question: Will heads support 300 HP?
 Post Reply Post Reply Page  123 5>
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
Buzzman72 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Sep/15/2009
Location: Southern IN
Status: Offline
Points: 2725 		Post Options Post Options   Thanks (1) Thanks(1)   Quote Buzzman72 Quote  Post ReplyReply Direct Link To This Post Topic: 327 Question: Will heads support 300 HP?
    Posted: Apr/29/2022 at 6:54pm
I know there's not a lot of go-fast parts available for a 327. I know the valves are rather small, and the combustion chambers aren't optimal for performance.

But I'm not looking to twist the needle off the dyno [I know they're digital these days]. But I'm curious whether mildly modified 327 heads can support 300 HP, using the stock 9.7:1 high-compression pistons and a relatively mild reground hydraulic lifter cam. And I'm talking naturally aspirated, of course, with 9.7:1 static compression. 

Ken Parkman, you likely can tell me off the top of your head. Rick Jones, I'd bet you could give me a few ideas. I know several others of the professional builders on this site could weigh in. 

The later AMC engines are more popular, but some of us are old-school and want to walk the road less traveled. Heck, if I wanted the latest and greatest, I'd be considering a late Hemi or an LS. But I've located almost enough parts to build an old-school Rambler, and I'd like to keep the engine Rambler. My goal with 300 HP out of a 327 would be a weight-to-power ratio of around 11 pounds per HP.


Edited by Buzzman72 - Apr/29/2022 at 9:04pm
Buzzman72...void where prohibited, your mileage may vary, objects in mirror may be closer than they appear, and alcohol may intensify any side effects.
Back to Top
SC397 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Apr/30/2009
Location: Michigan
Status: Offline
Points: 5480 		Post Options Post Options   Thanks (1) Thanks(1)   Quote SC397 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/29/2022 at 9:18pm
Kenny is the expert on the 327 cylinder heads and what they can flow. 
300 Hp is a stretch but not out of reach in my opinion. I would be more curious of the torque curve myself. Just a observation. In riding in my Buddy's 57 Hornet with a 327 in it, that thing pulls exceptionally well.  Granted, with the right gearing and the Hydromatic 4 speed trans the combo is pretty impressive - for the times. If you do some dyno pulls please note the torque curves.
Back to Top
PROSTOCKTOM View Drop Down
Supporter of TheAMCForum
Supporter of TheAMCForum
Avatar

Joined: Jun/20/2010
Location: Indiana
Status: Online
Points: 2458 		Post Options Post Options   Thanks (0) Thanks(0)   Quote PROSTOCKTOM Quote  Post ReplyReply Direct Link To This Post Posted: Apr/29/2022 at 11:07pm
Using a simple, small centrifugal supercharger with just a few pounds of boost will get you to 300 the easy way. Smile

Tom
Molnar Technologies Full Service Dealer - Crankshafts & Connecting Rods

1969 AMC Rambler Rouge Race Car
1974 AMC Hornet Hatchback, Wally Booth Outlaw Nostalgic Pro Stock Race Car Project
Back to Top
Rebel 327X View Drop Down
AMC Apprentice
AMC Apprentice


Joined: Mar/09/2021
Location: Toledo Ohio
Status: Offline
Points: 118 		Post Options Post Options   Thanks (1) Thanks(1)   Quote Rebel 327X Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2022 at 7:15am
The heads can improve with larger valves and removing casting issues. A reground cam with -+.480" lift and more duration lets it breath.  They next key is intake manifold. The stock cast iron intake is a restriction. Converting a Gen 1 or 2 aluminum intake to the 327 will get you to 300 hp easily as long as you have decent dual exhaust.  Fabbing up.some headers will help.  
Back to Top
Boris Badanov View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Dec/14/2013
Location: NH USA
Status: Offline
Points: 4210 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2022 at 9:39am
I agree, belt driven supercharger.

This will place the power in the driving range.
Gremlin Dreams
Back to Top
Buzzman72 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Sep/15/2009
Location: Southern IN
Status: Offline
Points: 2725 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Buzzman72 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2022 at 12:09pm
Originally posted by Rebel 327X Rebel 327X wrote:

The heads can improve with larger valves and removing casting issues. A reground cam with -+.480" lift and more duration lets it breath.  They next key is intake manifold. The stock cast iron intake is a restriction. Converting a Gen 1 or 2 aluminum intake to the 327 will get you to 300 hp easily as long as you have decent dual exhaust.  Fabbing up some headers will help.  

This is the kind of information I'm seeking. If you have a cam in the .480" lift range, is there a problem to fix in relation to piston-to-valve clearance? I'm thinking maybe 206-208 degrees @ .050" intake duration and 212-216 degrees exhaust duration @ .050, with about a 112-114 degree lobe separation angle so it will idle smoothly.

[I've also located a clutch bellhousing and fork, as well as a 3 speed trans with OD in case I decide to mate it to a manual transmission. Obviously, lacking a flywheel and ring gear, as well as pedals and clutch linkage, may "put the quietus on that notion." Looking to put this in a pre-62 Rambler. While the OD trans is set up for the torque tube, I'm also looking at converting to a '67-up "big car" 4-link 20-series rear end with Dr. Diff axles.]
Buzzman72...void where prohibited, your mileage may vary, objects in mirror may be closer than they appear, and alcohol may intensify any side effects.
Back to Top
SC397 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Apr/30/2009
Location: Michigan
Status: Offline
Points: 5480 		Post Options Post Options   Thanks (2) Thanks(2)   Quote SC397 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2022 at 12:27pm
I made these headers for Kevin by chopping up a set of 3 tube Pontiac headers.
It was my first attempt and building headers.  You will probably be better off starting from scratch.
 

This is the intake we made out of a Torker.
I was running the Sawsall and Kevin was holding the intake. LOL.


Edited by SC397 - Apr/30/2022 at 12:32pm
Back to Top
Buzzman72 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Sep/15/2009
Location: Southern IN
Status: Offline
Points: 2725 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Buzzman72 Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2022 at 12:35pm
Originally posted by SC397 SC397 wrote:

I made these headers for Kevin by chopping up a set of 3 tube Pontiac headers.
It was my first attempt and building headers.  You will probably be better off starting from scratch.
 

This is the intake we made out of a Torker.
I was running the Sawsall and Kevin was holding the intake. LOL.

Thanks so much for the visuals.
Buzzman72...void where prohibited, your mileage may vary, objects in mirror may be closer than they appear, and alcohol may intensify any side effects.
Back to Top
n2ojoe View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: May/04/2016
Location: Tecumseh, MI
Status: Offline
Points: 717 		Post Options Post Options   Thanks (1) Thanks(1)   Quote n2ojoe Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2022 at 1:02pm
Great info from the guys who have actually "been there, done that". 
Back to Top
amxron View Drop Down
AMC Nut
AMC Nut
Avatar

Joined: Nov/18/2011
Status: Offline
Points: 295 		Post Options Post Options   Thanks (0) Thanks(0)   Quote amxron Quote  Post ReplyReply Direct Link To This Post Posted: Apr/30/2022 at 11:41pm
Back in the early 60's Hot Rod mag had an article on the 327 in a 63 Ambo 2dr.

I seem to remember the car was in the low 13's with a mild build.

Ron.
AMXron
Fleet/Jeep Mgr.
Orbit AMC/Jeep
50-1787
Back to Top
 Post Reply Post Reply Page  123 5>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.141 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or