GT40P vs. E7TE
06-28-2006, 05:55 AM
#1
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GT40P vs. E7TE
Alright, here's my question. Many people on these forums go bananas over the GT40P heads. I have a set of E7TE heads on my rebuilt motor and absolutely love them. What are the advantages the GT40P heads over the E7TE heads? I thought the GT40P heads had slightly larger combustion chambers than the E7TE heads. So if that's the case, why use them?
06-28-2006, 06:49 AM
#3
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RE: GT40P vs. E7TE
From what I understand, the E7TE's have 60-62cc combustion chambers and the GT40's have something in the neighborhoods of 64cc combustion chambers. As for the flow of the heads, IDk... but wouldn't a good pocket porting even that up?
06-28-2006, 07:01 AM
#6
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RE: GT40P vs. E7TE
Its not opinion its a fact. Better flow means better HP.
I also read this chart. : http://www.corral.net/tech/powerplant/head_tech.html
And this little article I had saved when I was shopping for heads http://www.stangpro.com/html/article...les/gt40p1.htm
I also read this chart. : http://www.corral.net/tech/powerplant/head_tech.html
And this little article I had saved when I was shopping for heads http://www.stangpro.com/html/article...les/gt40p1.htm
06-28-2006, 07:22 AM
#7
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RE: GT40P vs. E7TE
If you know the reason why then you know facts. If you "know" they are and don't know why then all you have is an opinion because you have no proof or evidence to support your claim. The flowchart only shows the GT40 heads to have slight gains over the E7TE and the E7TE has smaller cc combustion chambers. I'ld rather not pay any money for heads and port what I've got then to go out and buy some used GT40s, port them and have a 2CFM advantage but a slightly lower compression ratio. Seems obvious to me.
06-28-2006, 11:06 AM
#8
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RE: GT40P vs. E7TE
are you talking about GT-40's or GT-40P's they are different.
there are several types of GT-40 heads........ GT-40's, GT-40P, GT-40Y and GT-40X
there are several types of GT-40 heads........ GT-40's, GT-40P, GT-40Y and GT-40X
ORIGINAL: sgt_pepper17
If you know the reason why then you know facts. If you "know" they are and don't know why then all you have is an opinion because you have no proof or evidence to support your claim. The flowchart only shows the GT40 heads to have slight gains over the E7TE and the E7TE has smaller cc combustion chambers. I'ld rather not pay any money for heads and port what I've got then to go out and buy some used GT40s, port them and have a 2CFM advantage but a slightly lower compression ratio. Seems obvious to me.
If you know the reason why then you know facts. If you "know" they are and don't know why then all you have is an opinion because you have no proof or evidence to support your claim. The flowchart only shows the GT40 heads to have slight gains over the E7TE and the E7TE has smaller cc combustion chambers. I'ld rather not pay any money for heads and port what I've got then to go out and buy some used GT40s, port them and have a 2CFM advantage but a slightly lower compression ratio. Seems obvious to me.
06-28-2006, 01:17 PM
#10
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RE: GT40P vs. E7TE
1st, both flow much better than the E7's. 2nd, the P heads flow better (up to .500 lift) than the GT40's due to changes in the exhaust port (removal of thermactor bumps for one). Above .500 lift, the GT40's will outflow the P heads. A little work on the exhaust ports on the GT40's will make them outflow the P's b/c they actually come w/ a larger exh valve...the thermactor bumps create a lot of restriction.
Click HERE and HERE
Click HERE and HERE