Hello Mustang fans,

I have finally removed my 289 from my Fastback and have it torn down ready for rebuild. It appears I will have to bore the cylinders. I have heard several different suggestions on how much you can bore a 289 out to.

It will have to be at least 40 thousanths but I could go 60. Some have said the walls are to thin to go 60, it this true? I plan to replace the rad with a larger 3 or 4 row, I am going up with the Edelbrock profermer package (Cam, lifers, Intake, and Carb) and the Edelbrock Performer Water pump. Out side of that it will be stock.

A friend of mine with the Mustang Club here in Abilene has a 289 block that came out of a 66 he will let me have for a buck and a quarter. I think if I go for it and keep my old block (matching number issue) I would be in good shape. The Block my friend has is at 30 now and there is plenty of room to go 40.

Any suggestions?

Thanks
Gary
66 Fastback

 

30 over is normal, 40 is pushing it, and 60 is radical. Talk to your machinist to see just how much you can push it, but if it were mine, I would not go over 40. The radiator upgrade/cooling upgrade you will like. Mine has the 4 row with a 5 blade fan and a recovery tank, and she runs cool enough during the hot summers in Texas with the air con on. I also added a shroud.

 

I thought you bought a stang that was in great condition already!? Are you just doing it for performance?

 

just remember the more you bore it out, the thinner the cylinder walls will get, and will heat up quiker. I suggest boring it on .30 over, and throwing a 3 row radiator in it, just to keep things "cool" as they say. You will almost have to bore out cylnders on a engine rebuild, so dont go overboard the first time around, it doesnt have to be extreme just streetable. I have that done in my Mustang and havent had a problem since. Good luck Gary!!

 

It is in great shape. But once I got the engine out I felt I should go ahead and do everything RIGHT. This way I know exactly what is in it. It will be beefy when I am done.
Gary

 

ya, if my dad and I can't afford a 351W thats what we were planning on doing. good luck man.

 

I talked to my machinist about the bore. He said that the culinders are at .40 now. We found a broken ring in #1. We feels with the condition of the walls now we would have to either go 60 or replace the block. Now the matching numbers issue come in. What do I do. As I stated above, I am upgrading the rad and going Edelbrok Performer all the way, but not sure if going 60 is a smart move. Thoughts?

 

Had a friend tried to bore a 289 .60 over and cracked the block. Think .60 is too much. Can't you just clean up cylinders and install sleeves?

 

.060 is way to much. .040 is ok. I ran a 289 for 6 years at that bore. .060 is a crack for sure and overheating. Use a 302 block, they are easier to find and usually in better shape. To my knowledge there is no matching number for Ford. GM used but not Ford. There is a date code but no where a VIN number, so that shouldn't be an issue. I do know where a complete 289 is. Quicker easier ting to do is find a 87 up 5.0 and bolt it in. They hardly wear and you have roller cam, forged pistons up to 92, they can be found from $250 AND UP.

 

Wouldnt do 60 over if it needs that much it should be sleeved. Sleeving is fairly pricy and only worth it if you want to keep that block for its date codes