Venomantidote95

Ok so these are supposed to be the stronger blocks??? can they be bored to .090 and be good to go?

I want to get 406 cuin with a shorter than 4in stroke!

On the other hand might go more than a 4in stroke! like a 430!

Need block limits for the D blocks?

uedlose

dont think they will go 90 at all, but yes they are stronger there seems to be more metal in the main bearing area. Lots of turbo guys are saying 800+ if you keep the rs down. I guess you can sonic test it to see how much you could safely bore it. I have seen 40 on lots of w motors and a few 60 but never 90

Venomantidote95

Ok was wondering i will be having that done to make the final decision though!

Wanted some insight from fellow engine guys, have only done 1 351 build and it was only 410 but only a .030 bore!
next question would it be worth going forged crank in this type production block, unlike the 302`s?

sn95_331_GT_ yellow

any regular SBF will only go to .040" SAFELY, yes you can go .060" but its a crap shoot. a 351C can go to .060" all day long, but thats the only one.

is the block bored over yet? usually going from .030 to .040 cleans it up...

D4 and earlier are the strongest in theory, about the only downside is not having a 1pc RMS, other than that they're good.

nothing wrong with a 4" stroke, just keep the rpms down and get ready to yank the front end lol

AdderMk2

I had a D4 block back a few years ago. It was already .030 and the machinist said he couldnt clean it up without going .060... then did it without asking me.


I no longer have a D4 block....

sn95_331_GT_ yellow

meh you dont need that extra 100lbs anyways...

AdderMk2

had they been able to clean the block at .040, I would be running that right now... with a B&G turbo kit...


this thread is making me sad....

uedlose

find someone that can sonic check the cly. walls before it is bored that will take all the guess work out of it period..

uedlose

LOL, I have seen many Cleveland blocks split down the cly. bore at 30 over, That is one of the main issues with Cleveland engines thin cly. bore walls due to core shift I have even seen a few that would not even go 30. and a small issue with a oiling problem at the mains at high rpm. That is some of the reasons they came out with the Clevor intake so you could use the W block with the Cleveland heads.

uedlose

it would be cheap insurance if gone with a big stroker and gone to spin it up and race it or use a power adder on it IMO. I have a few friends that run cast crank strokers with power adders that have been in the 9s and they have had no issues but it is gone to come down to your call. From cut up 400 cranks to cast steel Eagle and Scat and RPM stuff. I have a Forged crankshaft for mine with the hopes of when I go to a good block if I ever need to I will have the thing turned down on the mains to fit the 2.75 Cleveland style mains. and wont have to worry about upping the cash for a forged crank later if it will work out. That and I got a deal on the kit as the guy dropped a valve at 1200 miles and holed a piston and scared the cly. wall all up. Told me he was gone to put a Chevy engine in his car like it was a Ford problem that it dropped a valve. LOL good for me bad for him know what I mean..