Anybody ever put 440 Chrysler or 426 Hemi rods in a 385 series?

Just thinking. I know there's cheap offshore aftermarket rods now that will cost less and give more stroke.

But has the RB Chrysler rod been done? Is widening the journals on a cast factory 460 crank a problem? With offset grinding the stroke could end up around 3.97" and I think (?) you'd have a rod significantly stronger than the stock 460 passenger car rod? Custom pistons are no big deal these days IMO. Again, not looking for best bang for the buck with this idea.

any thoughts,

paulie

Before the cheap bbc hbeams were around it was done quite alot.

Its still more than some think......

It has been and IS done "all the time".

Before there were good cylinder heads readily available for a 385 engine it was common practice in a 429 to be able to use floater 460 pistons by just bushing the small end of the rods.

'Er, Changing the rods center to center length will NOT increase displacement....without other changes.

chuck stevens wrote:'Er, Changing the rods center to center length will NOT increase displacement....without other changes.

Was talking about offset grinding to 2.375" rod journal.

paulie

Thanks guys. I guess I'll never think of anything new!

I like the idea anyway.

paulie

plovett wrote:Just thinking. I know there's cheap offshore aftermarket rods now that will cost less and give more stroke.

But has the RB Chrysler rod been done? Is widening the journals on a cast factory 460 crank a problem? With offset grinding the stroke could end up around 3.97" and I think (?) you'd have a rod significantly stronger than the stock 460 passenger car rod? Custom pistons are no big deal these days IMO. Again, not looking for best bang for the buck with this idea.

any thoughts,

paulie

guys around here used to use 300 6cly rods in 429s

BOSS 429 wrote:

guys around here used to use 300 6cly rods in 429s

Wasn't it the 240 6 cylinder rods (6.78" bushed) they used with a factory offset ground crank you could get close to a 540" ??

The 240 rod is just under 6.8" in length, (6.7947"), and the 300 rod is a bit longer than 6.2" in length, (6.2097").

What's the rod journal size on the 240 rod? What about the big end width?

paulie

Looks like the rod journal for the 240 rod is 2.1236" or thereabouts. I haven't found the big end width yet.

paulie

chrysler rods are also .015 wider!

Hemi rod is a slightly different length than the 413,426,440 rod. Also these rods are all pretty heavy and a 6 Pak or Hemi rod is ABSURDLY heavy.

Proper use of a mopar 6 pak rod.

DaveMcLain wrote:Hemi rod is a slightly different length than the 413,426,440 rod. Also these rods are all pretty heavy and a 6 Pak or Hemi rod is ABSURDLY heavy.

They're lighter than the 1/2" thru-bolt 429 BOSS hemi rods, LOL.

I built a Boss 429 for a guy one time who had a set of those rods and the ones he had even had a pressure feed hole up the middle to feed the wrist pin, heavy duty.

DaveMcLain wrote:Hemi rod is a slightly different length than the 413,426,440 rod. Also these rods are all pretty heavy and a 6 Pak or Hemi rod is ABSURDLY heavy.

The RB 440 wedge rod is 6.76". The 426 Hemi rod is 6.86" and is exceedingly heavy. Even the 440 wedge 6-Pac rods are kinda heavy for most applications, so just use the standard 440 LY rod if you're building a BBF stroker with them. By the way, there are aftermarket I-beam 6.76 rods for a competitive price these days (versus reconditioning an OEM BBM rod).

Paul

the 440 rod doesnt have enough meat in the wrist pin end to bush for a floating piston, one major draw back

cooter wrote:the 440 rod doesnt have enough meat in the wrist pin end to bush for a floating piston, one major draw back

Nevermind floating the 1.094" pin bore, yikes. Instead, bush the 1.094 pin bore down to a 0.990" pin. And here's the beauty of it: Today there is a shelf piston available--the KB 856 & 857 pistons work perfectly with a 3.95" stroke.

Paul

p.s.: And the aftermarket I-beam rods are already bushed.

That's cool! It seems like this combo might be used in a lot of mud pit and/or pulling trucks. I think the cubic inches for a lot of those classes is in the 480-490 inch range? Right about where a 3.95" stroke gets ya.

paulie

paulie...back in the 80's I ran a 491 with offset stock crank to 3.965" and chrysler rods,ross pistons...it ran about 1500 quarter mile passes with both iron and alum heads before a rod broke mid beam,then we got some BME alum rods and ran it another 850 runs before the crank showed cracks at freshen up...max rpm was 6800 if I recall correctly..brian

birdracer wrote:paulie...back in the 80's I ran a 491 with offset stock crank to 3.965" and chrysler rods,ross pistons...it ran about 1500 quarter mile passes with both iron and alum heads before a rod broke mid beam,then we got some BME alum rods and ran it another 850 runs before the crank showed cracks at freshen up...max rpm was 6800 if I recall correctly..brian

Thanks for the feedback. Any idea what power it was making?

paulie

Gary Varney has ran a 490" BBF w/440 rods for years. If you know Gary,you know it's won it's share of races over the years. His bird runs 8.60's.