i am currently in the process of rebuilding my 66 mustang. it has what i think the original 289 v8 4c engine in it. it is the original engine, however it has been overhauled sometime in the past. my mom is the original owner and she never mentioned this. i came to this conclusion due to the fact that the pistons were stamped w/ the number 30, whick i assume means the block was bored .030 over and the pistons are no longer the original ones (also, they have a criss-cross pattern on the sides, is this normal for original pistons?). also i believe some of the rods were changed out. i read in a book that a 289 block will tolerate up to a .040 bore.

so, my question is, should i bore it to .040? put in sleeves? pros and cons? what are the alternatives if i want to use the original block? do i need to buy another new or used block? any suggestions? how much of the value of the car is lost if i find a used block built around the same time or put a new block in? just trying to narrow my options to make a decision. thanks.

 

How much do you want to spend??? That is the real driving factor.

A block with the correct casting date will not change the value at all. As for the rest, I am not sure on the spec's of the pistons/rods/block. Good luck [sm=smiley20.gif]

 

40 over is fine. It will run alittle hotter.

 

Does it need to be bored again? Are the cylinder walls damaged or ridged? What was the reason for the current rebuild?

 

Yea you could get away with a cleanup hone and just refinnish the jugs . As long as the piston to wall clearnce is in service limmits you are fine . thare is also a coupple of size pistons betwen .030 & .040 olny take out what you need

I would not sleave a 289 thare is to many of them out thare it would be a wast of money . If it was a 312 Y-block that might be your olny choise

Are you building this engin your self

 

the reason for the rebuild was because i thought it needed it since it's been 40 years, and it's a daily driver. i didnt know a rebuild had been done before. but i think it was time because bearings were worn, piston rings were cracked and other things. i basically just want it to run well for another 40 and also for the learning experience. i am doing the engine rebuild myself. i am just trying put a game plan together as far as what needs to be machined, what needs to be replaced and what i need to buy new. the cylinder walls seem to be in farely good condition, no severe scratches. i still need to mic them out to get more info. im gonna go as stock as possible this time around. cost is not really an issue yet, im just waying my options and seeing what makes the most sense.

 

If I was you I would take the worst looking pistons mark what cylinders each one came out of because its all balanced and take thim to the lokel parts store or machine shop too see what they say. As far as your block it would't be a bad idea to have the block check out to see if it needs any work at all but if you got broken rings I would definately have them checked out....... oh and if you have a 289 you can tele by the size of the sparke pluges they are much fater than a 302....

 

J i'm sorry, but you need some spelling help come on: lokel (not even close), wouldt, tele, sparke, pluges, fater? i hope this was late at night. The advice could use some help to!

 

Is there any wonder why potential employers question our educational system?

 

Leave him alone , this ant english class