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Discussion Starter #1
Hey Fellas

Have a few questions ... Had a 390FE built and the guy put a C1AE 6090-A head and a C4AE 6090G head on it. The car is a 69 Torino GT convertible...

1. OK to put mismatched heads on?

2. I'm kinda pissed cause I cant use my 69 exhaust manifolds. The bolt pattern is not the same... The newly build is an 8 bolt pattern.

3. I'm not sure what to use for exhaust now... The engine builder is telling me to get him the measurements of each head port so that he can help me to find a manifold or header... I spent a lot of cash... not feeling very happy ...

Any comments would be appreciated.
 

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The pair are pretty different. If you paid for this work, you got ripped off. I've attached 2 links showing the cylinder side, you can see the differences which will show in performance and probably longevity. You need to get the correct pair (or at least matching).

C1AE-6090-A

C4AE-6090-G
 

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I agree with CatSkinner. They could of at least matched the heads up. I hope the combustion chamber volumes match as quite often that varies from older to later model heads. Usually the later heads have bigger volumes for lower compression because of lower rated fuels.

I don't know if that is the case here but it's a worry with two different heads like that.
 

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Discussion Starter #4
The pair are pretty different. If you paid for this work, you got ripped off. I've attached 2 links showing the cylinder side, you can see the differences which will show in performance and probably longevity. You need to get the correct pair (or at least matching).

C1AE-6090-A

C4AE-6090-G


Appreciate the reply!

I'm looking for differences... I don't see any. Where in particular? The cylinder heads are turned opposite sides in the pics. Again appreciate the comments.
 

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It could be the carbon, but to me, it doesn't look like the chambers are identical. The casting on the C1AE is listed as 71cc, what isn't written on the C4AE is that it's chamber could be 71.2 to 74.2 depending on casting. Is it workable? Of course, but Ford had a reason for changing the design. In all actuality, the heads on a 69 Torino with a 390 are probably a C8AE-H... which are also 8 bolt.

I'm a stickler for a drive train being symmetrical. If you look up the horsepower ratings on an engine, you'll often see changes from year to year, one of the most common ways to gain power is through the heads. The 63 to 65 version of the engine was rated for 250 to 266 HP with a 2 barrel and about 330 with a 4 barrel, depending on which car or truck it came from. The later versions had about a 10 horse gain across the board. The primary difference is air flow through the engine since the bore and stroke really doesn't change, but the compression ratio probably does. For short cruises it probably won;t make a difference, but if you run a couple of long hauls or some extended periods of aggressive driving, one side may run hotter than the other.

I could be wrong on this, but I thought that FE's all had 8 bolt exhaust manifolds that were top to bottom. The Windsors were 8 side to side. How many bolts are on your exhausts and what pattern?

Cool car, BTW.
 

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Slightly off subject .There was an episode on Misfit garage when Thomas rebuilt the engine with two different heads .Apart from the problems they had on starting / running it , when the others guys seen the different heads they refused to use the engine as it was unprofessional and would look bad on them as a garage .Engine was pulled .
 
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