[BillH]

Just got a 66......I'm trying to figure out what engine it has in it....it has been modified or maybe even swapped.....Holley 4 barrel, Weiand intake manifold, Mallory distributor and Mallory Promaster coil.....none of the original stickers are on it...the door plate says its a 289....obviously no longer correct...the engine compartment has been redone...I can't find the plate that identifies the engine........I took the plugs out...they are Autolite 25's....the valve covers say "Powered by Ford"....

can you engine experts venture a guess as to what I've gotten into??

Thanks much...

[Cracker289]

Well there is not much information to go on, although I am curious as to why you say the 289 is obviously not correct. Could just as easily be a 289 with a Weiand intake and 4 barrel carb as a 302.

[krankieone]

There should be some casting numbers on the side of the block

[GBCityRestomod]

Cast Mark should be behind starter on block

[BillH]

Thanks for all the information.....I'll check and see if I can find the casting number.....I'm hesitant to work on it til I know for sure what it is....

Bill

[rodbender]

Maybe pop a vavle cover off and (if there's not a bunch of muck in the engine) check the inside for 289 or 302 casted somwhere There should be a date code on it too. This is considering the heads are original with the motor.

[wilit]

Originally posted by BillH
Thanks for all the information.....I'll check and see if I can find the casting number.....I'm hesitant to work on it til I know for sure what it is....

Bill

Why does it matter? Any part that will fit a 302 will fit a 289.

[BillH]

I didn't know that.....I really am novice I guess....the other oddity is that i purrchased new spark plugs ....told the guy 66 mustang 289 4 barrel...I saw him look it up on the computer and the plugs I got aren't even close to the old ones.........they won't fit the holes... the old ones are much smaller diameter on the part that threads into the head. What does that mean?

Thanks....

Bill

[Illuminati]

i say rip off a valve cover, it will say,

[rodbender]

What that probably means is ,at least the heads are later model. I'm not sure exactly when Ford changed to the smaller(5/8 socket) plugs. I'd say around early to mid seventies. My 69 351W still has the big plugs. But my 73 351C has the smaller ones. Hope this helps.

[BillH]

Every little bit helps me....thanks for your attention to it....what should I look for after I take off the valve cover?

[Acooljt]

They are incorrect for whoever said that everything is the same for a 289 and 302. They are the same engine, same block, etc. etc., but different stroke. You can't use any crank or rods or anything like that from a 302 and use them in a 289. Well, you can, but then it's no longer a 289. Just thought I'd throw that in.

Just check the casting numbers on the block. I don't remember exactly where they're at but I believe someone else above said where you can locate them. Take a wire brush and take any gunk off there and see what it says. You get those numbers and we can tell you everything you wanna know about that engine.

[68 GEE TEE]

you probably have a late model 302 engine, or at least the heads from one. Thats why the plugs are smaller. It's not a problem, as long as the engine is running good. As previously stated, crawl underneath the car and look in between the starter and oil pan at the bottom of the engine block. There will be a long part number starting with the letter C, D, or E. Copy down all the numbers and letters, post it here, and you will find out what year your engine is.

[BillH]

I'll post it as soon as I can so the experts can fill me in...thanks,....