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Topic Review (Newest First)
03-21-2018 04:28 AM
BuzzLOL
Quote:
Originally Posted by HotRodRay63 View Post
Rest assured Mr. Moderator that I will refrain from future posting on anything older than..... 3 days?

It might be expedient to put an automatic thread delete to threads older than 30 days.
[OLD THREAD]

Better to read a thread, check the dates, and make an intelligent guesstimate as to whether it is still active/applicable... whether the OP is still interested... any member can do a search themselves if there is old info they need...
03-20-2018 11:38 PM
4 Jaw Chuck We know who you are, just wanted to hear from you what your intentions are.

If your intentions are to cause problems we will solve them, I hope your intentions are otherwise...like helping others who post with your experience.

After all, thats what this place is for right, not for agendas or creating havoc or creating issues for the moderation staff right?

If you were a moderator what would you do?
03-20-2018 10:10 PM
HotRodRay63 Sir, i guess you are right.
Thank you for your candid observations.

I posted on this board for years and was asked to be a moderator. I declined.

Ive always been under the impression that people might actually read these threads to try to learn something. But I guess that I might be the only one that actually reads this stuff.

Rest assured Mr. Moderator that I will refrain from future posting on anything older than..... 3 days?

It might be expedient to put an automatic thread delete to threads older than 30 days.
03-20-2018 09:50 PM
4 Jaw Chuck HotRodRay63 You seem to be on a mission posting on old threads you dig up, how many pages back did you have to go to find this one...10?

Whats the point?
03-20-2018 08:57 PM
HotRodRay63 Gee Chuck. Looks to me that Nov 17, 2017 to Mar 20 is 4 months.

Ive been around 50 years and still learn some things.

Anyway, I look through oooold threads trying to learn something and sometimes post to help somebody else. Like starfish.

Maybe threads should be deleted completely when they get a few months old. Naw...

Today I looked at a freshly assembled 302 INstalled a car, not yet run, and the right head gasket is on backwards. They said I was nuts.
Yeehaaw.
03-20-2018 12:34 PM
4 Jaw Chuck Another old thread, look at the original posting date before responding.

A year old!
03-20-2018 10:15 AM
HotRodRay63 I conclude from the OPs rocker arm question that he has a pre 74 heads now... using either GT head will knock almost one full number off the compression, worse than the old 351 head swap of 40 yrs ago...

and the newer heads dont have the ports of the old 351W.
03-20-2018 10:08 AM
HotRodRay63 See Post #12 ..... 4 lines is the P heads.... therefore 3 lines are the plain gt40.

They have hard seats but around 63 cc chambers. 302 heads with the fat spark plugs are smaller.

302 heads with the 5.0 type rocker arms starting in 74 had small spark plugs and big chambers. The same head was used on the 351W.
03-20-2018 10:00 AM
BuzzLOL
Quote:
Originally Posted by RobbyDD View Post
I dont know what cam is in there.
6 years ago I put in a crane cam but I don't remember what it is now.
It has flat top pistons.
A lot of people tell us they have flat top pistons, then submit a picture and they have a large diameter shallow dish with 4 valve reliefs, that's why we always question/double check that statement... sorry... Has the engine been rebuilt? Pistons replaced?
03-20-2018 09:52 AM
BuzzLOL What HP engine was your 302 when new?

What RPMs range does the Crane cam pull in? 1000 - 5000? Up to 5500? Up to 6000? Up to 6500? Is it a solid or hydraulic cam?

GT40/GT40P heads are better than other 1970's heads... don't know if better than 1960's heads... there are instructions online on how to distinguish GT40 from GT40P heads...
03-19-2018 04:16 PM
HotRodRay63 97 was a split year. Lates had P heads with 4 bars lines cast on the end. Need different headers to clear plugs.

Big combustion chambers. @62-65 cc nominal. Compression?

The 68 302 4bbl had 54cc heads but a slightly dished piston. There 3 different dishes through the years and heads up to 65 cc on the smoggers.

Assuming stock lift cams, Flattops with valve reliefs with stock valves will clear ok unless you mill the heads, then be sure to clay them.

Milling the heads' deck requires also milling the head's intake surface, or .... you can ruin the intake manifold by milling it and making it unuseable on any other engine.

Sometimes you can squeeze by using extra thin intake gaskets to make up the distance shrinkage of not milling the head intake surface.

Stock Mountaineer rockers work fine with stock 302 pushrods... All this assuming youre sticking to a low lift - .478 cam.

You might expect 25 hp increase minus any compression loss.
11-19-2017 10:39 AM
OneMoreTime On any of my engine builds i use the clay. never mind do not argue with the old guy just do it. Only takes one blown motor to cure you...

A fellow can get by if he is just doing a valve job on a stock motor..

Sam
11-19-2017 07:35 AM
64nailhead
Quote:
Originally Posted by RobbyDD View Post
I'm thinking I might just leave the heads the way they are and just bolt them on.

Im not sure what rocker arm ratio to use. I was thinking I could use the stock ones on the gt 40 heads. Then use a dial indicator and see how much lift the cam has for intake and exhaust. Then look up the ratio of the stock rocker arms and calculate the valve lift. And see if that is too much for a 302? Will this work? Or do i need to use clay or something
You're in need of a cam degree kit, either bought or homemade. There is no better time than the present to learn. Also, aspects of degreeing a cam are a much easier task with the heads removed.

JEGS Precision Cam Degree Wheel Kit | JEGS

Putting this together and experiencing some piston to valve contact, broken valve train components due to coil bind or poor rocker geometry makes degreeing the cam seem like a function that cannot be excluded.
11-19-2017 01:44 AM
BogiesAnnex1
Quote:
Originally Posted by RobbyDD View Post
I'm thinking I might just leave the heads the way they are and just bolt them on.

Im not sure what rocker arm ratio to use. I was thinking I could use the stock ones on the gt 40 heads. Then use a dial indicator and see how much lift the cam has for intake and exhaust. Then look up the ratio of the stock rocker arms and calculate the valve lift. And see if that is too much for a 302? Will this work? Or do i need to use clay or something
The problem isn't one of maximum lift but rather too much lift on the valve as the piston closes at TDC. To do a computation you would need to know the lift in crankshaft degrees and the piston position in the bore at those degrees, you gotta know a lot about the cam timing and lift rates and be able to due a lot of trigonometry to find where the piston is in the bore to crank degrees, this is not linear because as the crank turns the apparent length of the stroke changes and the connecting rod whose length is important is opening and closing different forms of triangles. This makes pulling a head and sticking a blob of clay on a piston then reassembling everything then turning the crank around, then taking the head off again to measure the clay look pretty simple.

Bogie
11-19-2017 01:41 AM
JeffB28
Quote:
Originally Posted by RobbyDD View Post
I got a pair of GT40 heads out of a 97 mountaineer.

I'm going to put them on my 302 in 67 mustang.

I was thinking I should get the heads resurfaced to get a higher compression ratio?

What is a good ratio to use where I can have as much compression as possible on regular gas?
1997-2001 Mountaineer 5.0's used the GT40P cylinder heads if you have headers this can cause an issue with the spark plugs not clearing the tubes,the earlier GT40's are OK. Both the GT40's and GT40P's valve springs will not support a higher lift cam than stock so you need to address that also.
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