I recently picked up a D4AE 351w Block and crank for a rebuild. When I torn it down it was .060" over already. The cylinders looked to be in good shape. It had a .0025" ridge at the top. The Shop Manual specs the bore to be 4.0000 - 4.0048. I have measured 4.063 on most , but have one at 4.065. These measures are after final honing. Used a ridgid hone to make round.

So it appears the block is still in spec to put new pistons in. However I think I heard .030" - .040" was about all a 351W wanted to go. Although You can get pistons.

Current build plan is for a 79 150 4x4 - Speed pro hyperutechtic pistons flat top, reconditioned stock rods, Stock crank .030" under, D0OE heads, Performer intake, Comp 4x4 cam .477/.493" lift, holley 750 dp. And very rarely a shot of 100 hp nos. This motor is short term - just a couple of years, Then maybe a 427W.


I am just looking for input as to whether or not this block will work for me. or if I should keep looking for another.

Thank You

 

30 over is the factory recomendation,but some blocks can go more.My buddys has a 302 with 60 over pistons in his stang.

 

More than 30 over and they tend to run hot.

 

I've heard about running hot, and was think that I have a three core truck Radiator. But I don't know if it would help or Not. If I Had it sonic check for wall thickness what would be a good measure of thickness?

 

If worse comes to worse you may think about having the block sleeved.

 

Have the block sonic tested to see if the walls are too thin.

 

.060 over on a 351w is fine, especially the older blocks. You have to be careful with the later, US blocks because the main webbing is thinner and the walls are a little thinner, I believe. .060 is fine and .030 is about as much as you want to grind off the crank mains. If you only intend to have the block perform for 2-3 years, you shouldn't see any issues if the machining is done correctly and the pistons, rings, wrist pins and bearings are new. Make sure the machinist pays strict attention to the cross hatch put on the cylinder walls. If they do not hold oil well they will fail much more quickly expecially bored out that much. Racers will bore many 351w blocks out to .120 over and get many runs out of them. I am finishing a .060 351w right now. I'll have pics up on my site and I fully expect to get 100k out of it or more. with thinner walls, I also recomment running minimal water as coolant...you want to de everything possible to minimize corrosion on the other side of the cylinder wall. The suggestion to sleeve the block is not a bad idea either, but you are getting to the point where rebuilding and doing that much work is about the same as getting a fresher or new block. Good luck! http://hometown.aol.com/auxpower

 

i had a .060 over 5.0 in my 89 stang and it was a 90 truck block so it was a weaker block and it worked just fine. i put a 3 core truck radiator from my 82 supercab in the car and the temp stayed around 230. no big deal, the stock gauges show that 270 is overheating. i then got a 2 core aluminum radiator but the bearings went before i could use it. anyway. it is not too bad but it would cost more money to sleeve the block then you may want to spend on it.

 

Honestly, I see little reason to bother going .060 over. I myself, wouldn't want one that is more than .030 over....the blocks are pleantiful enough still, you can just get another block and bore that .030 over and be good to go....

It may cost you a little more time/effort that way, but atleast you're getting something you will know is going to be ok.