400 block motor mount compatability

[Cranky]

Nothing runs like a mopar. Well....maybe OJ Simpson I guess.

Oh man, that was funny! You do plan on sticking around here, right!?

 

[Stroker68]

Oh man, that was funny! You do plan on sticking around here, right!?

Yeah...ill be around. Lots of stuff to click on.

 

[Cranky]

Yeah...ill be around. Lots of stuff to click on.

Just as long as you're using a scoop....or not

 

[1 Wild R/T]

It's not too hard to make a stock stroke 383 run pretty good and the same goes for a 400. Yes, the 400 was considered a smog motor with it's low compression but who these days is still running a stock 400? I know there are some out there but not many. 400's used to be cheap just because of that and most of them have cast cranks but Mom's cast cranks are much better than the GM cast cranks and don't fail like the GM stuff. A 383 forged crank will bolt into a 400 but yeah, needs to be rebalanced. I'll take a big bore short stroke engine with mayo any day! Too many think a 400 is worthless unless you stroke it.....and that's not true.
.

Thing is there's limited piston availability & the short stroke makes it hard to get a decent compression ratio without going to a domed piston....

Yes, the can run but it's easier & way more powerful when you slide a longer arm in the engine...

 

[1 Wild R/T]

Thanks Wild. I like the idea of the 470. Should be enough room for a half inch pickup. 4.25 stroke might get a little tight and require an external oil system. Good info on the true of the cranks. I've got a lot reading to do.

I like the 470 allot, and since it uses a 2.20 rod journal there's lots of room...

But the 512 also uses the 2.20 for journal & an internal pickup fits fine...

FWIW current thinking is the 1/2" pickup cause more problems than it solves..

 

[Stroker68]

Snipping a couple thou off the block and running a smaller cc chamber head can up compression for a stock rebuild. Painting it mopar orange adds at least 100 horsepower.

 

[Cranky]

I like the 470 allot, and since it uses a 2.20 rod journal there's lots of room...

But the 512 also uses the 2.20 for journal & an internal pickup fits fine...

FWIW current thinking is the 1/2" pickup cause more problems than it solves..

I like the 470 too...and am helping someone with that build now. Thing is, a stock stroke 400 will act very well with the right stuff in it and without slinging a big.....well, you know

 

[Stroker68]

I like the 470 allot, and since it uses a 2.20 rod journal there's lots of room...

But the 512 also uses the 2.20 for journal & an internal pickup fits fine...

FWIW current thinking is the 1/2" pickup cause more problems than it solves..

Yeah...a 2.20 is a standard chebby spec journal. That would help for clearance issues. With the 4.25 the 3/8 pickup will do just fine. Hemi use a 1/2 pickup. More oil on the twist. More rpm. More oil. I spin my junk to 6800. 1/2 pickup.

 

[Stroker68]

I like the 470 too...and am helping someone with that build now. Thing is, a stock stroke 400 will act very well with the right stuff in it and without slinging a big.....well, you know

Agree. Rotating mass isn't always your friend.

 

[1 Wild R/T]

Agree. Rotating mass isn't always your friend.

Thing is most of the stroker bob weights are significantly lower that the standard stroke bob weights... On my 440/512 the piston & rod assy is over a pound lighter that the original parts... At one time 440 Source was also offering gun drilled lightweight cranks...

 

[1 Wild R/T]

Actually they still do... But only for the 4.25 stroke... An additional 6.5 lbs off the rotating assy... For a $150 fee..

http://store.440source.com/Ultralight-Crankshaft/productinfo/44042506800-6-LW/

Correction, not gun drilled, but lightened

 

[Cranky]

How is it lightened? I've done a little bit of that over the years and the shops that have to balance it don't like it lol

 

[1 Wild R/T]

Follow the link..

http://store.440source.com/Ultralight-Crankshafts/products/184/

Thing is they know their rotating assy so it will still balance

 

[Cranky]

Price is up there....plus, what kind of twist do they have.....?

 

[1 Wild R/T]

Price is up there....plus, what kind of twist do they have.....?

I personally have no idea but there are plenty of them out there running well into the 9's & some are in the 8's...

 

[Stroker68]

Actually they still do... But only for the 4.25 stroke... An additional 6.5 lbs off the rotating assy... For a $150 fee..

http://store.440source.com/Ultralight-Crankshaft/productinfo/44042506800-6-LW/

Correction, not gun drilled, but lightened

They push it for the 4.25 because of the inertia of the rotating mass. Its a hefty assembly. Ok for a street motor, but a race application that sees over 6000 rpm, balance is everything. Brand new factory motors balance around 28 grams or more and run smooth. You'd never know. High end crates around 16 grams. NASCAR 4 grams and under. That's why they stay together at 8000. Tales a lot of work to make all that weight work in harmony. Lots of technicals umm hmm.

 

[1 Wild R/T]

They push it for the 4.25 because of the inertia of the rotating mass. Its a hefty assembly. Ok for a street motor, but a race application that sees over 6000 rpm, balance is everything. Brand new factory motors balance around 28 grams or more and run smooth. You'd never know. High end crates around 16 grams. NASCAR 4 grams and under. That's why they stay together at 8000. Tales a lot of work to make all that weight work in harmony. Lots of technicals umm hmm.

Have you found this chart yet?

 

[Stroker68]

Have you found this chart yet?
View attachment 829445

Bob weight for the crankshaft must be balanced with the bobweight of the piston, rod and rings. The number they show is for the overall assembly i believe. Lots of technicals. Have to remove weight from crankshaft to balance with others. The difference between is what matters. Like within 4 grams of each other for Nascar.

 

[Stroker68]

Is why some factory motors run strong and some don't IMO. I'm sure the 512 will buckle some pavement. Torque monster.

 

[cryplydog]

Some shops can balance the assy. with the flywheel/pressure plate and the balancer/pulley together. I like that idea.