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4-3/8" crank in a 440 anyone run one?

Posted By: RTSrunner

4-3/8" crank in a 440 anyone run one? - 02/24/17 08:27 AM

Just wondering how one of these is compared to the more common 4.15"/500" combo.The idea of a 526"+ BB sounds cool,I'm thinking low RPM street vs race,3.54 geared,four speed etc. Any opinions on cylinder heads or flow needed for this type setup?
RT
Posted By: Cab_Burge

Re: 4-3/8" crank in a 440 anyone run one? - 02/24/17 09:00 AM

I've put two 4.375 stroke 440 motors together for bracket racing, the first one was with a single 1050 Holley Dominator carb on a Indy 440-3 intake and a set of Indy SR M.W. heads. It made 775 HP at 7000 RPM on a DTS engine dyno in Klamath Falls,OR at 4300 Ft. elevation shruggy
The same short block, intake, carb and a set of CNC ported 440-1 heads made 845 HP two weeks later on the same dyno with very similar weather, the motor had a interment miss starting at 5200 RPM and missed all the way up to 7500 RPM due to the dyno header flanges where smaller than the exhaust ports whiney realcrazy
On your deal a set of 440-1 heads that are mildy ported and make the short block have less than 10.8 to 1 compression for pump gas should be a real tire spinning rascal, in any gear work 750 + HP easy with decent heads, intake, cam and carb up shruggy
The SR M.W. port heads lowed 340 CFM at .700 lift on the intake side and the CNC ported 440-1 heads with 2.250 intakes flowed 370 CFM at .700 Both sets had 1.65 ratio Harland Sharp single shaft rockers and both had solid roller lifter cams that had .700 net lift at the valves with both sets of heads. The other 440 motor had smaller heads and a smaller cam and made right at 700 HP also shruggy
I really want to warn you that most factory 440 blocks may have a main web failure around 700 + HP with bad gas or a bad tune on pump gas whiney work
If you are willing to build a 400 short block with the same parts, you can beat on it harder without worry work twocents
Posted By: gregsdart

Re: 4-3/8" crank in a 440 anyone run one? - 02/24/17 01:47 PM

I built a 4.5 stroke motor with only about 270 cfm head flow (iron heads), made lots of low end grunt but was all done by 5700 rpm. Cab hit the nail on the head, 440 blocks are known to not last well over about 650 hp. If you do build a 440 block motor, shoot for a very light rotating assembly and a very safe tuneup. Personally, if it were my deal I would look for a good set of small port heads that flow around 290 to 300 cfm and cam it to pull from about 3500 (260@ .050 duration?) to 6,000 max, and enjoy it for a long time.
Posted By: Stanton

Re: 4-3/8" crank in a 440 anyone run one? - 02/24/17 03:56 PM

I used the 4.375 crank in my RB street motor but in hindsight should have gone for 505 or 512 instead of the 526 c.i.. I think you can get just as much power with the fewer cubes and you don't need to bore .060 over. Some will argue but you pretty much need to go with the external oiling with the 4.375 crank.
Posted By: cudadoug

Re: 4-3/8" crank in a 440 anyone run one? - 02/24/17 08:49 PM

Originally Posted By Stanton
I used the 4.375 crank in my RB street motor but in hindsight should have gone for 505 or 512 instead of the 526 c.i.. I think you can get just as much power with the fewer cubes and you don't need to bore .060 over. Some will argue but you pretty much need to go with the external oiling with the 4.375 crank.


Why do you have to bore .060 over?

I just mocked up a 4.375 crank with 2.200 rod journals and it fit okay, will clear a 3/8 pick up although it was close. I also realize that every block is NOT identical...

***edit: not identical
Posted By: Stanton

Re: 4-3/8" crank in a 440 anyone run one? - 02/25/17 01:06 AM

To get the 526 c.i. the op is talking about you need the 4.375 crank and a .055 overbore (I said .060 ... sorry my bad !!)

And I did say "some will argue" !!!
Posted By: FastmOp

Re: 4-3/8" crank in a 440 anyone run one? - 02/25/17 01:07 AM

Put the 4.5 in it
Posted By: cudadoug

Re: 4-3/8" crank in a 440 anyone run one? - 02/25/17 02:36 AM

Originally Posted By Stanton
To get the 526 c.i. the op is talking about you need the 4.375 crank and a .055 overbore (I said .060 ... sorry my bad !!)

And I did say "some will argue" !!!


I wasn't arguing, just tossing in my findings on ONE example.

I skipped over the OP talking about bore size. I thought you were saying it had to go .060 like maybe that was only piston available or something.
Posted By: RTSrunner

Re: 4-3/8" crank in a 440 anyone run one? - 02/25/17 03:28 AM

I didn't do the math to figure the 526",maybe it is closer to 520 with a more standard .030 overbore. I saw a few sets of pistons for sale with the correct CH for the 4.375 stroke which is what sparked an idea.Only speculating at this point,and Cab,I do have a low deck as an option wink Thanks for the info guys.
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