Hulk0202

Im a little confused if I'll have any problems here. Thanks

RB83L69

That would depend on what pistons you use. If you put stock 400 pistons in there, they will poke out the top of the block about .125", so there will be a minor clearance issue between the pistons and the heads. Other than that, no problem.

They do make pistons for that combo, but they're not cheap.

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"So many Mustangs, so little time..."
ICON Motorsports

AlkyIROC

The aftermarket pistons move the wrist pin up into the oil control rings.

There's nothing wrong with using the 400's 5.56" rods. Polish the beams and install ARP bolts.

The 5.7" rods need to use the 400's style of rod bolts and clearances need to be checked at the bottom of the cylinder and at the cam.

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zroc

if I remeber correctly the rod journals for a 400 crank are larger than the 350 journals so you may have to have the rod journals cut down for the 5.7 rod unless you go w/ an aftermarket custom rod...

zroc

AlkyIROC

Journals are the same size. The mains on the 400 crank are larger.

Damon

Steve's right. Also, if you use 5.7" rods you use standard rod bolts, not 400-style. They're totoally different bolts and they are not interchangable. Yes, you will have possibly some clearance issues at the bottoms of the bores where the rod bolt nut will come close to striking (not nearly as big a deal as it would be if you were building a 383 from a 350 block, though). Also, the HEAD of the rod bolt may have interferece problems with a few of the cam lobes, but this varies from cam to cam so it's difficult to say for sure.

Again, this is minor-league grinding compared to building a 383 with 5.7" rods.

prscarf

stick to a 5.7rod or 6"rod and go with aftermarket pistons. shorter rods have increase rotational angles from the wrist pin to the crank journal. longer rods are better, just searh any stroker website.

i just built a 383 complete with all the goodies.

crazeinc

a 383 is just a little different than a 400 though...

jcb999

drop me email if interrested. I have a set of 030" over Kb139s (400 w/5.7 rods), that have 20 hours on them.

[This message has been edited by jcb999 (edited November 21, 2001).]

Ed1LE

iTrader: (39)

I had a 406 in my old 84 SS monte. 400 + .030". I was running stock (reconditioned) 5.7 rods w/ KB 125 pistons (10.1 compression w/ 76cc heads-fairly inexpensive but nice). The rods did need some grinding for block clearance by the rod bolts (don't remember exactly where b/c it's been 4 years) but it was nothing major. Your machine shop would figure it out I'm sure when doing the machine work & balancing. Also, as mentioned above, you need 5.7 rod bolts, the 400's are to short (I remember finding out the hard way). It's an awesome way to go....awesome displacement, power range & performance. The motor dyno'd around 460hp @ 6200RPM's & 450lbs. of torque @ 3500RPM's (guess-tamits based on memory, got specs at home somewhere) making it an incredible street motor!!! Drop me a line if you want more info...I still have all the paper work & specs on the motor.
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'91 Z28 1LE; 355, Sportsman II heads, Edelbrock TPI w/ 58mm TB, Tremec TKO 5-speed, 3.73's & much, much more

[This message has been edited by Ed1LE (edited November 21, 2001).]