Author Topic: 1968 gt 500 heads  (Read 2330 times)

427heaven

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1968 gt 500 heads
« on: June 27, 2020, 11:36:30 AM »
What would the casting numbers be on a set of 1968 thermactor heads?

The Going Thing

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Re: 1968 gt 500 heads
« Reply #1 on: June 27, 2020, 11:41:26 AM »
There would be two possibilities.  It would depend if it was a KR or not. 428 Vs. 428 CJ. I have seen C8AE-H on Non-CJ engines and C8OE-N on CJ engines. I wouldn't be surprised if there were others.

427heaven

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Re: 1968 gt 500 heads
« Reply #2 on: June 27, 2020, 04:26:48 PM »
Non KR standard GT 500- With thermactor holes for air pump. Approximate value ?

Coralsnake

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Re: 1968 gt 500 heads
« Reply #3 on: June 27, 2020, 07:29:20 PM »
About a $100 each

There is a large supply, because its the same as 390

427heaven

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Re: 1968 gt 500 heads
« Reply #4 on: June 27, 2020, 08:28:40 PM »
Ok thanks. Nothing on the left coast goes for a 100, but I get they must be common.

The Going Thing

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Re: 1968 gt 500 heads
« Reply #5 on: June 28, 2020, 05:27:49 AM »
They are probably the most common head out there. They were used on everything.  Low performance standard fe valves. They're on ebay and Craigslist for 1-200.00 a pair.
The N heads are actually a performance head and fetch 1,000 to 1500 a set. Most unless looking for date code correct run Edelbrocks. Cuts 50 lbs off, runs better than the N head and can be bought for less than proper reconditioning of the iron heads.

shelbydoug

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Re: 1968 gt 500 heads
« Reply #6 on: June 28, 2020, 09:27:06 AM »
They are probably the most common head out there. They were used on everything.  Low performance standard fe valves. They're on ebay and Craigslist for 1-200.00 a pair.
The N heads are actually a performance head and fetch 1,000 to 1500 a set. Most unless looking for date code correct run Edelbrocks. Cuts 50 lbs off, runs better than the N head and can be bought for less than proper reconditioning of the iron heads.

So you would recommend the Edelbrocks?
68 GT350 Lives Matter!

Royce Peterson

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Re: 1968 gt 500 heads
« Reply #7 on: June 28, 2020, 11:10:59 AM »
They are C8AE 6090-H drilled 14 bolts on the exhaust pattern and drilled for Thermactor. I see them for sale at $300 - $400 a pair. They were the same part used on 1968 390GT Mustang / Cougar / Comet / Fairlane so not only were lots made like that, lots of people still need them. If I had a 1968 GT500 I would be looking for a properly date coded pair. This would narrow the field significantly and it might make you consider paying a higher price for the right part.

The same castings were used on all sorts of low performance Ford, Ford truck, and Mercury products so a clever machinist can make the less valuable 8 bolt / non - Thermactor versions fit and work.

If you need more performance these heads respond well to larger valve sizes and porting.


Ok thanks. Nothing on the left coast goes for a 100, but I get they must be common.
1968 Cougar XR-7 GT-E 427 Side Oiler C6 3.50 Detroit Locker
1968 1/2 Cougar XR-7 428CJ Ram Air C6 3.91 Traction Lock

427heaven

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Re: 1968 gt 500 heads
« Reply #8 on: June 28, 2020, 01:03:09 PM »
Much appreciated, Thank you.

The Going Thing

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Re: 1968 gt 500 heads
« Reply #9 on: June 28, 2020, 01:52:17 PM »
They are probably the most common head out there. They were used on everything.  Low performance standard fe valves. They're on ebay and Craigslist for 1-200.00 a pair.
The N heads are actually a performance head and fetch 1,000 to 1500 a set. Most unless looking for date code correct run Edelbrocks. Cuts 50 lbs off, runs better than the N head and can be bought for less than proper reconditioning of the iron heads.

So you would recommend the Edelbrocks?
Yes, without a doubt. These are the ported heads done at KBE. The valves were changed to 2.25 Int 1.75 EXH.

shelbydoug

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Re: 1968 gt 500 heads
« Reply #10 on: June 28, 2020, 02:10:16 PM »
how did you use those with a 428 block? The 427 blocks were notched to clear the intake valve at 2.19". A 428 is only 4.13 bore vs 4.23 stock.
68 GT350 Lives Matter!

The Going Thing

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Re: 1968 gt 500 heads
« Reply #11 on: June 29, 2020, 02:08:16 AM »
The valve angles are changed in the Edelbrocks.  They clear with the HR/TP valve size on a 4.155 or larger bore.