odd stroker combo.

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Thenwhat85

Thenwhat85

built not bought
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north royalton, Ohio
im planning a new engine for my duster drag car. this with be a a bracket motor in a 2720lbs w/me in it chassis car. know parts.Virgin 400 block, enderal bird catcher, indy tunnelram alcohol injection for induction. heads will be (for now) promaxx heads ported to max wedge intake. external twin line oiling. BCR mains/girdle system .Now im thinking 512 or 470 but with 1.122 ch pistons. the 470 would use a 6.86 rod leaving .043 for decking. the 512 will use 6.7 rod and leaves .033 for decking. whats you take? i know the pistons or short but it is just a bracket motor. should i be worried about the skirts coming to far out of the bore at bdc? what other issues could i be over locking.
 
Thenwhat85 said:
im planning a new engine for my duster drag car. this with be a a bracket motor in a 2720lbs w/me in it chassis car. know parts.Virgin 400 block, enderal bird catcher, indy tunnelram alcohol injection for induction. heads will be (for now) promaxx heads ported to max wedge intake. external twin line oiling. BCR mains/girdle system .Now im thinking 512 or 470 but with 1.122 ch pistons. the 470 would use a 6.86 rod leaving .043 for decking. the 512 will use 6.7 rod and leaves .033 for decking. whats you take? i know the pistons or short but it is just a bracket motor. should i be worried about the skirts coming to far out of the bore at bdc? what other issues could i be over locking.
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Unless you already have crank or rods ,
you could also do a 499 - 4.15, 6.76, 1.122
 
Piston skirts coming out of the bore at BDC is not an issue since these designs have been in use for a long time proving themselves just fine.

IMO, the less you need to deck the block the better.
 
Stroker Kits-440 Source

2F564718-4354-485A-B01C-6B1ED3F31D26.png
 
the 470 deal i found new aluminum grp rods for a good deal at 6.86 length thats why i thought about that combo. i like the idea of a 512 but the 6.535 with 1.32 puts you at zero deck and we all know the block isnt square.
 
If you end up out of the hole a little just use a thicker head gasket
 
yeah id like to stick with steel shim is i could alot cheaper than cometic not against paying more just makes it alot easier on the wallet if the heads need removed
 
If you end up a zero deck I would use at least a .039 felpro, if your like .010-.012 out of the hole use .051 felpro
 
yeah but how much typically needs taken off to square the deck? i know it varies im not reasy to take to machine shop yet still in the planning stages
 
Thenwhat85 said:
yeah but how much typically needs taken off to square the deck? i know it varies im not reasy to take to machine shop yet still in the planning stages
Click to expand...

1966 440 BLOCK , TOOK .002-.003 , TO SQUARE THE DECK ------------
 
Thenwhat85 said:
yeah but how much typically needs taken off to square the deck? i know it varies im not reasy to take to machine shop yet still in the planning stages
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If you use aluminum rods you ain’t going to run .039 deck clearance. I’ve run as tight as .055 with them and I was cleaning off the little bit of carbon there was.

RPM, piston weight and how flexible all your parts are will determine minimum piston to head clearance but it won’t be much under .050 for sure.
 
yellow rose said:
If you use aluminum rods you ain’t going to run .039 deck clearance. I’ve run as tight as .055 with them and I was cleaning off the little bit of carbon there was.


RPM, piston weight and how flexible all your parts are will determine minimum piston to head clearance but it won’t be much under .050 for sure.
Click to expand...

I don’t know how I got away with it but years ago (still have short block) I bought a 498 short block with pistons .03 in the hole. 4.15 MP crank, 7.3 BME, 1.3 JE. I took it apart to freshen and had block decked .030.
Re Oringed block and Reused the .04 sce copper gaskets that it came with. Added 440-1 heads and a 200 shot and never had a problem. ......8.90s @ 150, Guess I was lucky

Just read .060 on BME site, I’m gonna have to take a closer look at the short block and gaskets. Heads are long gone.
Maybe I’m wrong
 
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604B1duster said:
I don’t know how I got away with it but years ago (still have short block) I bought a 498 short block with pistons .03 in the hole. 4.15 MP crank, 7.3 BME, 1.3 JE. I took it apart to freshen and had block decked .030.
Re Oringed block and Reused the .04 sce copper gaskets that it came with. Added 440-1 heads and a 200 shot and never had a problem. ......8.90s @ 150, Guess I was lucky

Just read .060 on BME site, I’m gonna have to take a closer look at the short block and gaskets. Heads are long gone.
Maybe I’m wrong
Click to expand...


Yeah, everyone says .060 but I’ve run it at .055 and there were some witness marks of blowing he carbon off the pistons so I didn’t push that any further.

In fact, that was when you could get Groden connecting rods. I don’t know what happened to that guy but his rods used dowel pins to locate the caps and not serrations. The BE stayed round much better and longer with the pins, and his were billet.

I may not push a forged rod beyond .060 but I might have when I was younger.
 
well i found diamond pistons with a 1.305 ch so that puts me .015 in the hole on 9.98 deck with the 4.25 stroke 6.535 rod. think this is the route im going to take granted the block doesnt need decked alot
 
Good choice, that should work real nice.
I have a .030 over 383 block that came with a 440source stroker kit. 4.25 with 6.535 and flat tops. I’ve been thinking about swapping out the block and pistons for a 400/4.375 bore before putting it together. Good luck with the build, ....keep us posted !
 
Fast01 said:
Or 517 with 4.250, 6.700, 1.122 and take .030" off the deck to bring it to zero. Kinda like I did.
Click to expand...
yeah i think thats the route im going. i like the light pistons i was just curious if they would stick out the bottom bore too much and rock excessively at bdc
 
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