289/302 heads.

Dave Moors · Mar 19, 2007

HI all,
I've been offered a pair of 302 heads in better condition than my existing (i think) 289 heads that will allow me to get back on the road quite a bit quicker but can anyone tell me where I can find info on the differences between the 2 head types and if I need to do anything to the block?
Thanks

danny clemens · Mar 19, 2007

Depending on the year 302 heads it could lower your compression quite a bit and hurt performance.

toolwench · Mar 19, 2007

Yeah, it depends what the heads are out of/what year they are. If you just wanna get the car running, that's a whole other ball of wax, too.

I mean, after toasting a motor, I cleaned the rust off an old shortblock and went to the junkyard to get heads out of anything 302 just to get back on the road. I ended up with heads from a 70-something T-bird and that motor ended up lasting me five years. I saw about 120 on the freeway one night and it didn't sound like it was going to explode. When I swapped it out for a crate motor, the only thing wrong was a leaking front main. It has now been cannibalized into two other motors.

streetdemon70 · Mar 19, 2007

so if i put 289 heads on my 302 will it bump compression?

D.Hearne · Mar 19, 2007

streetdemon70 said:
so if i put 289 heads on my 302 will it bump compression?

Depends on what 289 heads you're talking about. They're not all the same. The early ones had a small 54 cc chamber. The later ones grew to 58 or 60 I think. The so called 68 Stang "J" code 302 heads were simply recast early 289 heads (C6OE) and had that same small 54 cc chamber, hence the 10.5 to 1 comp ratio. 302 heads had 54, 58, 60, 64 and 79 cc chambers, depending on the head casting.

mustangguy289 · Mar 19, 2007

Ive got some hopped up 65 yr model casting 289 heads. larger valves dobl springs port etc. Pm me if interested also have the cam and lifters that match springs.

streetdemon70 · Mar 20, 2007

pm sent

Dave Moors · Mar 20, 2007

I spoke to the seller and they are allegedly from a 91-94 302 motor. The existing engine i am told came out of a 67 cougar. Can handle the loss of some performance esp if it helps me get on the road sooner. Plus our gas prices are going up again as our government goes all "green".
Thanks for assistance.

toolwench · Mar 20, 2007

I could be wrong, because I honestly don't remember for sure, but when I was junkyard-hopping for a set of heads I could use, the later ones had some sort of smog inlet or something. It wasn't that they wouldn't mate to the block, but that there was essentially a hole in the head that needed to be addressed. I chose the oldest set in the yard so that I wouldn't have to deal with any oddities like that.

Once again, I could totally be wrong because I don't remember for sure, but it'd suck to get all the way into it and excited about getting the thing together only to find out you've got another thing to deal with. I hope I'm either wrong or that it's not a big deal.

Soaring1 · Mar 20, 2007

Heads

What you really want to find are some gt40 heads.

D.Hearne · Mar 20, 2007

If you 67 heads are the following casting numbers : C7OE-B, C7ZE-A, C8OE-D, L, OR M, These have 63 cc chambers, E7's are 64cc. Mill them up to .040 and you'll gain some compression.

streetdemon70 · Mar 21, 2007

so if i put some 65model 289 heads on my stock 70 short block 302 what compression ratio would i be looking at? what was stock for a 70 302?

Pakrat · Mar 21, 2007

IMHO if you really want to wake up a 289/302 with a stock head than you should be looking for a set of 69-74 351W heads. If a port is too small it may yield velocity from low end torque but it has no performance when it is time to open the throttle, the engine just struggles too much to breath. The 351W's are a great compromise and if you bother with a good port and bowl job it's an outstanding stock head.

D.Hearne · Mar 22, 2007

streetdemon70 said:
so if i put some 65model 289 heads on my stock 70 short block 302 what compression ratio would i be looking at? what was stock for a 70 302?

Depends on what pistons you have now. This combo is essentially what the 68 4 bbl 302 was (J code) 10.5 to 1.

mustangguy289 · Mar 22, 2007

Posted this same question about the 65 head on a 70 302 on corral.net here was one the only answer so far.

If it is a true 1970 piston, the one with the small dish (not a flat top 4 eyebrow), then the 54cc 289 head is going to bring it up to around 9.5:1. The 1970 set-up would have been using the 58cc head and had around 9:1. So for this geometry, the 4 cc smaller combustion chamber is going to increase Cr by ~ 1/2 a point. this is for the stock configuration and a gasket thickness around .040, deck clearance .012.

streetdemon70 · Mar 23, 2007

thanks man. pm sent back

jeffnoel · Mar 23, 2007

Check out this chart for compression ratios when swapping heads.

http://www.mustangii.net/headswapcompression.asp

289/302 heads.

Dave Moors

New Member

danny clemens

Member

toolwench

New Member

streetdemon70

New Member

D.Hearne

New Member

mustangguy289

New Member

streetdemon70

New Member

Dave Moors

New Member

toolwench

New Member

Soaring1

Banned

D.Hearne

New Member

streetdemon70

New Member

Pakrat

D.Hearne

New Member

mustangguy289

New Member

streetdemon70

New Member

jeffnoel

Similar threads

289/302 heads.

New Member

Member

New Member

New Member

New Member

New Member

New Member

New Member

New Member

Banned

New Member

New Member

New Member

New Member

New Member

Similar threads

Privacy & Transparency

Privacy & Transparency