I have a 1965 289 that I bought 27 years when I was 18. I was told by the guy that sold it to me that it was a HiPo. I bought the bellhousing, flywheel, 11 in clutch and the pressure plate with it. Problem is that the heads do not have the cast in spring cups and are cast numbered wrong. Casting numbers are C5AE-B. But the heads do have screw in rocker arm studs and 1.78 in intake valves. From what I've read, standard 289 valves are 1. 67 in.
If I decode the casting number correctly. These are (C) meaning1960's, (5) meaning1965, (A) meaning Full size, Galaxie, (E) meaning engine.
Do I have somerare heads, or do the Galaxie heads come with the screw in studs and bigger valves, or do I have a good machine job that was done years ago?
Al

 

From what I have found, I have a 1965 4barrel, 225 hp, 289. The valves and ports are the same as the cupped HiPo heads. In 1965 both the HiPO and the 1965 4bbl had 10 to 1 compression. NHRA Super Stock cylinder head volumes list the C5AC-B as the best flowing stock 289 head made. No other head flows as well. As a matter of fact, after this head the flow goes down.
According to my MOTORS manuals, (I have 1965 and 1971), the 289 4bbl was never offered in a full size car. My C5AE-B heads don’t have the spring cups, but I never had a problem showing off with 8,000 rpm burnouts. I bought the motor from a guy that had built it just for drag racing. He said it was balanced, blueprinted, and stroked to a 302.
I know when I beat 383 Roadrunners and 428 SCJ Mustangs it sure felt like it was. I ran it with a 4 sp. in a 1969 Mach 1.
I bought the motor with the bell housing, flywheel, 11 in. clutch and pressure plate. From what I have found, these are special 289 HiPo pcs. The bell housing is different from standard to accommodate the 11 in. clutch and pressure plate.
I have kept the motor and clutch pieces stored in a barn for 25 years. Believe it or not, the top end looks like I just parked it and tore it apart. I will be looking for a 65 mustang to put it in.
Al

 

I have taken off my bellhousing and flywheel. After searching the part numbers online, these are not 289 HiPo pieces. The flywheel is a C5AE-6380-A/C7TE-A. I have not found this exact flywheel yet, but it does take an 11 inch clutch and pressure plate. I know, I have it and used it. The Bellhousing I did find. It is part number C5TA-6394-A, cast iron. This was used in the early 1971,BOSS 351, MACH 1's. So I have to assume this is where the flywheel came from. So I was sold a good motor, but not a 289 HiPo. What the heck, I was 18.

 

sounds to me like the heads were machined. especially since it has screw in studs.

 

I bought my stang when I was 13 with my dad. We didnt know anything about all the swapped parts from other year type cars. I thought i bought a v8 1965 Ford mustang coupe. And everything in it was 65. I am now getting a little bit smarter in the research and all. I have a 65 Body with a 65 Hood from another car I found out, and a 68' 302 V8 4bbl holley. However, all the breaks and etc are all manual. So at least I know that is 65. But as long as it runs WOO HOO!!!!

 

The heads could have been machined. The guy I boughtthe motorfrom said it was built by a Dana Corp. employee in his freetime. It is supposed to be balanced and bueprinted. I dont know what cam is in it, but with solid motor mounts it shook my car like a big block. With a family I've never had the money to get another car. Now my kids are older and I'm starting to look for a 65 to put the motor in. I want to get Alum heads for it, and I'll check the part# on the cam and see if I can find out who made it and what the specs are.
I had a stroke a year and a half ago and was out of work for 4 months, and part time for even longer. That drained the bank account pretty bad. I can use all my parts and hope to work on cars for a hobbie.

 

My 1965 "Motor's Auto Repair Manual" (p. 753) states that v-8 221 and 260 engines used press in studs and that 1965 289 engines used threaded studs.But my 1971 book states that threaded studs were used on HiPo 289 and HO 302 engines.
So either the 65 book is wrong or some 65 heads were threaded but most units went to push in studs.
If you check the NHRA head flow chart the C5AE-B heads I have are the best flowing 289 head. And the heads did come with the same size valves (1.78 intake) as the HiPo heads.

 

I think the 65 book is wrong. All but the K code heads were sposed to be push in. Its one of the key identifiers of k code heads that they have screw in studs.

I have a slightly different take
c5 as stated
A -FORD
E - Engineering Group (E for engine)
B- Second iteration. (Engineering changes made to the part. So the stock was C5AE-A (or C5 O Fairlane, D Falcon, Z Mustang E - Engine)...it is certainly confusing.

Re the bell housing...I'm pretty sure that the 11" clutch and matching housingis the larger bell housing and wont fit in a 65. I think you can onlygo to a 10.5 clutch and a smaller but samebolt pattern bell housing is needed.

 

I believe that if you look at the heads under the valve covers, it says 289 and there will be a "dot" or 2 "dots" right above the 289 lettering. 2 dots is for the HiPo.

 

my heads dont even say 289 underneeth the valve covers, thats weird...