dumb question about 390 GT heads

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69rangerf100
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dumb question about 390 GT heads

Post by 69rangerf100 »

ok so here is the deal i found a set of 390 GT heads on ebay that has local pick up here in GA. my question is will a standard 390 intake bolt to the GT heads. FYI i have an edelbrock 4 barrel intake on my 390
David

Dream as if you'll live forever, live as if you'll die today - James Dean

Daily Driver - 1998 Honda Accord
Wife's Ride - 2007 Ford Explorer Sport Trac
Project - My Dad's 1969 F100 Ranger 390 w/ 3spd manual coming soon PS, PB, A/C and alot of paint and body work - Miss you Dad
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BobbyFord
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Re: dumb question about 390 GT heads

Post by BobbyFord »

Yes, the intake will fit.
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69rangerf100
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Re: dumb question about 390 GT heads

Post by 69rangerf100 »

sweet thanks for the info Bobby. now i just have to hope that the sell will sell them for the starting price of $75

here is the description he posted

1968 Ford FE 390 Heads C8AE-H Ford , Fairlane, Mercury Cougar . This a complete set / pair of heads that i got off of a 68 mustang a long time ago. These are in the way on my work bench & i have no use for them at the present time. These have the 14 hole bolt pattern for the exhaust manifolds. Date code is 9017 . PICK Up Only, Email for phone number. Thanks for looking.
David

Dream as if you'll live forever, live as if you'll die today - James Dean

Daily Driver - 1998 Honda Accord
Wife's Ride - 2007 Ford Explorer Sport Trac
Project - My Dad's 1969 F100 Ranger 390 w/ 3spd manual coming soon PS, PB, A/C and alot of paint and body work - Miss you Dad
http://s936.photobucket.com/albums/ad208/69rangerf100/
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Re: dumb question about 390 GT heads

Post by onetuford »

I wonder if there is any difference between the C8AE-h's I found on a stock 360, other than the 8 hole exaust manifold pattern.
"I'm not saying, I'm just saying"

1972 Ford F250 C/S XLT 390 NP435, purchased from the son of the original owner, now named Yoda
1967 Ford f100, currently. (2nd Titled owner) Now named Captian Hook
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69rangerf100
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Re: dumb question about 390 GT heads

Post by 69rangerf100 »

well that is the casting number that is on the heads i am looking at getting
David

Dream as if you'll live forever, live as if you'll die today - James Dean

Daily Driver - 1998 Honda Accord
Wife's Ride - 2007 Ford Explorer Sport Trac
Project - My Dad's 1969 F100 Ranger 390 w/ 3spd manual coming soon PS, PB, A/C and alot of paint and body work - Miss you Dad
http://s936.photobucket.com/albums/ad208/69rangerf100/
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Re: dumb question about 390 GT heads

Post by onetuford »

I did a little searching this afternoon on the fe forum and found out they (ford) put these heads on everything. That would explain why I found a set originally installed on a stock 360 motor. I also have a set on a 1970 390 two barrell car motor. What would these heads be replacing?
"I'm not saying, I'm just saying"

1972 Ford F250 C/S XLT 390 NP435, purchased from the son of the original owner, now named Yoda
1967 Ford f100, currently. (2nd Titled owner) Now named Captian Hook
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My427stang
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Re: dumb question about 390 GT heads

Post by My427stang »

True statement, a GT head is better described as a "small port truck head drilled for unibody car exhaust manifolds"

They are absolutely nothing special. D2TE-A (truck only) and C8AE-H (truck and car) are identical and on almost every truck out there from 68+
71 F-100 SB 4x4, 461 FE, Edelbrock Pro-flo 4, 4 speed, 4 inch softride lift, all poly bushings, integral PS, most mods installed since the 80's
70 Mustang Sportsroof 489 FE, EFI, TKO-600 5 speed, 4.11s
Engine building by-appointment only--30+ years, specializing in strong street pump gas FEs
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Re: dumb question about 390 GT heads

Post by Hawkrod »

My427stang wrote:True statement, a GT head is better described as a "small port truck head drilled for unibody car exhaust manifolds"

They are absolutely nothing special. D2TE-A (truck only) and C8AE-H (truck and car) are identical and on almost every truck out there from 68+
I disagree with that statement completely. First off, the ports are smaller but it was an efficiency design, not a truck design. On a mild engine the smaller port made for better velocity and fuel atomization which makes for much more efficient engine operation. The smaller ports actually helped improve power in the lower RPM ranges that cars usually operate at. THe C8AE-H (and C8AE-I) heads are a very good mild head up to about 5000 RPM but at that point they fall off fast. The other thing I disagree with is the C8AE-H and the D2TE-A heads are only similar. The D2TE-A head is actually a significant improvement over the C8AE-H with slightly better port design and the chamber changes make for a significantly better combustion process. It is all about efficiency. These heads were a big improvement over the earlier larger port heads because they were designed to improve the combustion process and they do a great job. That is not to say that the earlier heads can't be better, it is to say that in stock applications, the later heads perform the task they were designed for much better from the factory. BTW, the D2TE heads are worth a few HP on the dyno over a C8AE-H with no mods at all! Finally, to the issue of GT heads, A GT head is the same as a truck head of the same year as far as the casting goes. It has the same ports and chambers, the same valve sizes etc... What makes it a GT head is the exhaust side is drilled with a different bolt pattern to fit GT manifolds (truck manifolds will not bolt on) and they have different valve springs. There is no potential power gain from running a GT head over the truck head. Hawkrod

As you can see in the pics below, the C8AE-H and the D2TE-A heads do have different chamber designs (it is a common misconception that they are the same, probably because very few people have actually bothered to look due to the lopo nature!):

Image

Image
39 Ford Dlx Cpe
59 Tbird 430
60 Lincoln
(2)62 Tbirds
(3)68 Cougar XR7-G's
69 Cougar 428CJ 4 speed
77 1/2 F250 4X4
86 SVO
76 F250 Crew Cab
67 F250 Ranger
http://www.supermotors.org/registry/veh ... 9&detail=1
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Re: dumb question about 390 GT heads

Post by onetuford »

I assume the bottom pic is the C8 version? So you mean to tell me that with a mild build, like say an Eldelbrock Performer 390 intake, 600 cfm 4bbl carb and proper cam choice I am better off going with the set of D2TE-AA's over good set of C8AE-H's I've got laying on the shelf? This would be for a .030 over 390. One more thing. If my cylinder walls are good on my 360, And I threw in my 390 crank and rods with the 360 truck pistons I would have a pretty high compression ratio. Would these D2TE-AA's be a better choice than the C8's? And since I'm on this topic, what advantage do I get with the 4v intake and carb over a say a 500cfm Holley two barrell.
"I'm not saying, I'm just saying"

1972 Ford F250 C/S XLT 390 NP435, purchased from the son of the original owner, now named Yoda
1967 Ford f100, currently. (2nd Titled owner) Now named Captian Hook
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Re: dumb question about 390 GT heads

Post by Hawkrod »

Actually, the bottom one is the D2 chamber. It may not be intuative looking at it but the D2 and C8 chambers are the same size but the C8 chamber is deeper and has a smaller opening which creates a larger quench that has blind spots (places where unburned gases hide). The deeper chamber also shrouds the valves reducing flow even though they are the same size. The D2 chamber is actually a much better design and is more similar to the old 427 chamber but with smaller valves. I will tell you that I have used D2TE heads on a number of projects that were not restorations (which I rarely normally do) and when numbers don't matter and the choice is from normal production low performance heads the D2TE is my first choice for street driven vehicles. Now, having said that, I would always choose properly ported heads designed for the applications when I am building something that is not so mild! LOL Hawkrod

427 chambers (sorry, could not find a better size pic!):

Image
39 Ford Dlx Cpe
59 Tbird 430
60 Lincoln
(2)62 Tbirds
(3)68 Cougar XR7-G's
69 Cougar 428CJ 4 speed
77 1/2 F250 4X4
86 SVO
76 F250 Crew Cab
67 F250 Ranger
http://www.supermotors.org/registry/veh ... 9&detail=1
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Re: dumb question about 390 GT heads

Post by onetuford »

Cool. Thanks for the insight.
"I'm not saying, I'm just saying"

1972 Ford F250 C/S XLT 390 NP435, purchased from the son of the original owner, now named Yoda
1967 Ford f100, currently. (2nd Titled owner) Now named Captian Hook
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