hey guys im lookin at a 64 390 outta a t-bird. guy claims its 10.5:1 cr all original. are these good heads on the 64 t-bird 390? whats the valve size? he sez I need to run 91 octane or else itll knock....it only has 2 engine mount holes so thats early FE right?

 

Probably 10.1 on the CR as OEM.

Yes, premium fuel, and lots of it....

2.02/1.55 on the valves. Most FE heads are "good" and will support a fair amount of power over the stock outputs. However, your heads will have the buttery valve seats of yesteryear, when manufacturers relied on lead in the fuel to protect the seats--sorta. Valve jobs at 40,000 miles were not unheard of in the day. Most lasted much longer, of course, but remember, in '64 a car was pretty much junk at 100k.

The cork in an FE motor like that is the exhaust manifolds. Look at 'em. They look more like plates bolted to the ports to keep them closed up than manifolds....

Yes, 2 bolt mounts are early mounts, '65 was the change.

This thread is going the other way--truck FE into 'Bird, but it has a lot of info:

https://www.ford-trucks.com/forums/1...-a-t-bird.html

FE info, some typos:

FE Series Engine Specification Chart

 

Ditto all the above...

The 10.5:1 CR may be correct though, those early FE's ran on the "good gas", not the crap we have today.

Do you have the numbers on the heads, just cuz it's a '64 block doesn't meant the heads are '64....but if they are they're pretty decent heads.

 

Octane requirement will depend on the cam used. If you keep the stock cam, then yea, it'll need 91-93 octane. Swap the cam to something like Crane's 272* Energizer and it'll be fine with 89 and 12* initial timing.

 

I was told it has 268h cam. he showed me the cam card. it idles real nice. kinda aggressive but not to radical you know. im just spooked bout needin to run 91 or 93. can I get away with runnin 87 or 89 on this engine? moneys tight so every penny counts and 87 is $3.69 91 is $3.99

 

That's a decent cam...

My junk is 390 10:1 CR and I run 87 octane without issues (pinging)

If you want, buy it.

 

The 268H is made for engines with the compression ratio down around 8 to 9 to 1. You can try 89, but I don't think it'll like the lower octane. You can also try it while also dialing back the timing too, to see if that helps.

 

I realize it's a long shot on a 50yr old motor but is the engine ID tag still intact? the seller claims "all original" so maybe it is....

If it's a "P" code '64 390 the CR will be 10.5:1

If it's a "Z" code '64 390 the CR will be 10.1:1

This is assuming it's all original and stock.

 

it does have the tag on the coil bracket. the seller emailed me what the tag reads... 1st line....390 64 11.....2nd line....8 M K 373 P

I know what the 390 and 64 is but whats the other stuff mean?

 

The data I have shows that being a '64 390PI (police Interceptor) 330hp, 4bbl, 10.5:1cr, assuming that tag came off that motor.

What car does the seller claim the motor came from?

 

you could always swap heads to the 72 cc later heads , that will drop your C/R

 

Not relevant to this thread, but that "good gas" just had it's sins covered by adding lead

 

It's funny that aside from having to deal with ethanol blended gas,(and the problems that brings) the "crap gas" we have today seems to work fine with 9-11 to 1 compression ratios, and at a lower octane than the "good gas" of the 1960's

 

Montana does that mean it came out of a cop car? the seller said a t-bird. were there any t-bird cop cars?

 

I seriously doubt it's a "P" code 390 if it came from a T-Bird.