Head Questions
Thread Starter
|
Freshman User
Joined: Feb 2003
Posts: 40
Likes: 0
Head Questions
I am rebuilding my 1970 F100's 302 and I plan on upping the ponies a bit I am looking for around 300 horses, and similar torque numbers. I am told that these heads are brutal for exhaust breathing, so I was looking into alternatives. The ford guys up here want 1200 bucks for a set of GT40 p heads, so I was thinking a set of 289 heads with bigger exhaust valves for breathing, and the smaller combustion chamber for better compression. Any advice you could provide would be great!!
Scott
Scott
Posting Guru
Joined: Mar 2002
Posts: 2,070
Likes: 2
From: Boise, Idaho
Head Questions
Be aware that Ford switched from broached pushrod slot for guiding the pushrods, to slotted rockers. The slotted rocker setup uses longer valves.
C5AE heads have tiny combustion chambers. You can have them reworked with Ch@vy valves, 1.94/1.6 or maybe use slightly smaller Ch@vy 1.8/1.55 valves. The 1.94 are cheaper but you might get some shrouding. These (C5AE) heads have slotted pushrod holes - you'll need hardened pushrods. Again, Ch@vy rockers can be used.
You'll want to have the exhaust ports ported and hardened exhaust seats.
Good swirl, excellent quench, even with stock valves and ported exhaust, these heads would work great on your 302.
C5AE heads have tiny combustion chambers. You can have them reworked with Ch@vy valves, 1.94/1.6 or maybe use slightly smaller Ch@vy 1.8/1.55 valves. The 1.94 are cheaper but you might get some shrouding. These (C5AE) heads have slotted pushrod holes - you'll need hardened pushrods. Again, Ch@vy rockers can be used.
You'll want to have the exhaust ports ported and hardened exhaust seats.
Good swirl, excellent quench, even with stock valves and ported exhaust, these heads would work great on your 302.
Thread Starter
|
Freshman User
Joined: Feb 2003
Posts: 40
Likes: 0
Head Questions
Are the stock 302 heads really that bad or is this guy just trying to get me to pay a bunch of money to have him rework them?
If they are really bad breathing heads can they be ported and have larger exhaust valves put in?
I should tell you I am aiming for app 20-25 mpg and about 300 hp, with a nice flat torque curve, around 300 foot lbs.
Is this reasonable for these heads? How much work will it require of these heads without a large cam (I want to run a 204,214 duration cam) I do plan on a edelbrock preformer intake, headers and dual exhaust.
If they are really bad breathing heads can they be ported and have larger exhaust valves put in?
I should tell you I am aiming for app 20-25 mpg and about 300 hp, with a nice flat torque curve, around 300 foot lbs.
Is this reasonable for these heads? How much work will it require of these heads without a large cam (I want to run a 204,214 duration cam) I do plan on a edelbrock preformer intake, headers and dual exhaust.
Elder User
Joined: May 2002
Posts: 627
Likes: 0
From: Claremore, Ok 74017
Head Questions
you can order world products windsor jr's for around 800 from jegs and summitracing. They breath real good and I have not had a problem with them. You will need heads like this to produce hp # like your looking for. They have a 58cc combustion chamber
180cc intake runner
160?cc exhaust runner
1.94/1.6 exhuast valves.
180cc intake runner
160?cc exhaust runner
1.94/1.6 exhuast valves.
Elder User
Joined: Aug 2002
Posts: 662
Likes: 0
From: CA
Head Questions
Summit also has the GT40P heads for $538 American a set including valves and springs (at least they did in their October 2002 catalog on page 25), but when using these heads you'll have to search for the right headers. Hedman supposedly makes a set that are supposed to fit. You have to dimple one tube, but it's a major dimple.
Posting Guru
Joined: Jan 2003
Posts: 1,061
Likes: 0
From: Still under the hood in O
Head Questions
Summit used to have the 'p' heads (p/n FMS-M-6049-P303), I was going to order them this week and noticed they are no longer available!
Just found them here for the same price...
http://www.need-4-speed.com/fordracing.htm
Just found them here for the same price...
http://www.need-4-speed.com/fordracing.htm
Last edited by 90f150moneypit; Apr 9, 2003 at 09:35 PM.
Senior User
Joined: May 2002
Posts: 375
Likes: 0
From: nc
Head Questions
300 hp will be a pretty big task with the stock heads. the torque figure that you are after can be found in the stock head. i agree with the other guys, in terms of the gt 40 heads. i would not spend any money on trying to improve the stock heads. you can easily spend as much as an aftermarket set would cost and still not acheive your goal.
Thread
Thread Starter
Forum
Replies
Last Post
fireman660r
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
30
Feb 20, 2009 11:17 PM
Scott_McGee16
Performance & General Engine Building
7
May 16, 2007 03:03 PM
ScottP460
1987 - 1996 F150 & Larger F-Series Trucks
3
Mar 28, 2003 01:15 PM
