....never heard of anyone saying +40 is too much... .030 and .040 are just about your most popular oversizes on any engine

noone has said that would be too much...

 

It shouldn't be..... .060 is maximum overbore any machine shop will do.... so, you are still within specs..... Your engine builder should be aware of any deficiencies, and will more than likely check wall thickness before boring in any event.

 

the friend that originally helped me said they've done .120 on DART blocks before, but ik this is no dart block

 

Yeah, Dart makes good stuff. certainly FAR stronger than stock... parts for that size overbore are hideously expensive though, and make hen's teeth look downright common.

 

you would think, but i beleive he said they used like a .060 over piston from a larger bored engine, so i guess it depends on what your final bore size ends up at

 

Have em sonic check the block. You have to if you plan on going 40 over. Mopar blocks are famous for Core shift, and poor castings...Just like the Heads...Even some Magnum R/T Heads I've had were junk and had to be sent back. Some blocks are better than others.

When I do a stroker, it's gonna be on a stock bore, 20 over max. A Magnum block aint no 340 block, and a lot of machine shops don't know the diff...Figuring a small block Mopar is a small block Mopar.

 

now you have heard it 2x. 40 OVER on mag blocks is a no no. Thin walls=hot running motor.
When you use custom pistons to set the quench. Deck the block to zero is a much better way to set.
KB slugs need to adhere to there top ring gaps if you go with them. loose is the word here otherwise you will break the top ring land in no time.

 

im just not understanding this... there are plenty of MAGNUM 410 strokers out there.

you are saying dont go .040 period and adobe and HeyYou says as long as i get it sonic checked. if this is the case my project is over for the time being.

there is someone on this forum who went .060 no problems

 

That's why I'm saying to get the block checked out, they are all different, some better than others. You could be on the edge at 30 over...Mopar is famous for their core shift in everything they cast.

But personally I would not go 40 over on a magnum block....Go over to Moparts.com and do a search.

 

ok ill have it sonic tested. that will show whether or not i can go 40 over.

im not trashing the block on an assumption, so to speak