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451 stroker cam/rod clearance?

Posted By: polkat

451 stroker cam/rod clearance? - 07/16/09 06:57 AM

When dropping a 440 crank with the main journals, and counterweights (and block) clearanced to fit into a 400, has anyone also run into problems with rod (short) or rod bolt clearance and/or any problems with cam (MP brand) clearance? I haven't gotten this far in my build yet, so I'm just asking to know ahead of time. Thanks!
Posted By: JohnRR

Re: 451 stroker cam/rod clearance? - 07/16/09 12:17 PM

Not that I have ever seen posted about, if it were an issue it would have been in Andy F's 451 manifesto .
Posted By: bobbyb

Re: 451 stroker cam/rod clearance? - 07/16/09 12:43 PM

Good question, cause I plan on the same build this winter.
Posted By: Dcuda69

Re: 451 stroker cam/rod clearance? - 07/16/09 01:24 PM

I did a 470"/400....I had no problems with clearance.
Posted By: RodStRace

Re: 451 stroker cam/rod clearance? - 07/16/09 02:15 PM

I've got a 451 with aluminum rods and a roller cam that has over .600 lift (at the valve). No issues.
I've never heard of a cam/rod issue with a 451.
Posted By: 70Cuda383

Re: 451 stroker cam/rod clearance? - 07/16/09 02:32 PM

yea, I've not heard of cam/rod or cam/crank clearance issues on 451s...it's not THAT much stroke! the bottom half of the 383/400 is the same as the 440, right? don't they use the same timing chains? the differences in the block are all at the deck height aren't they?

if they are the same, then there should be no reason why a 440 stroke would run into issues with the cam in a block with factory dimensions--or for the most part, factory dimensions.

I may be wrong here though on the bottom half of the castings being the same.
Posted By: JohnRR

Re: 451 stroker cam/rod clearance? - 07/16/09 03:34 PM

Quote:

yea, I've not heard of cam/rod or cam/crank clearance issues on 451s...it's not THAT much stroke! the bottom half of the 383/400 is the same as the 440, right? don't they use the same timing chains? the differences in the block are all at the deck height aren't they?

if they are the same, then there should be no reason why a 440 stroke would run into issues with the cam in a block with factory dimensions--or for the most part, factory dimensions.

I may be wrong here though on the bottom half of the castings being the same.



No, the bottom of the cylinders are lower , the cam on the other hand is in the exact same location as the 440
Posted By: 70Cuda383

Re: 451 stroker cam/rod clearance? - 07/16/09 03:39 PM

Quote:

Quote:

yea, I've not heard of cam/rod or cam/crank clearance issues on 451s...it's not THAT much stroke! the bottom half of the 383/400 is the same as the 440, right? don't they use the same timing chains? the differences in the block are all at the deck height aren't they?

if they are the same, then there should be no reason why a 440 stroke would run into issues with the cam in a block with factory dimensions--or for the most part, factory dimensions.

I may be wrong here though on the bottom half of the castings being the same.



No, the bottom of the cylinders are lower , the cam on the other hand is in the exact same location as the 440



Thanks John! so then the only thing you should really have to worry about then, is clearance at the bottom of the cylinder walls? (until you get some really big strokes into the 400 block)
Posted By: JohnRR

Re: 451 stroker cam/rod clearance? - 07/16/09 03:44 PM

Yes and that's why a 440 crank needs the counterweights cut down , or the bottom of the bores notched for counterweight clearance .

I bought a crank from MP , it was on CLEARANCE , 5140 forged, 3.75 stroke, 8 BOLT for a LOW DECK . I get it , put it in the block ... DOES NOT FIT , after looking at it and thinking about it I determined it was the SAME crank sold as a REPLACEMNT for the 426 HEMI , all they did was spec the MAIN SIZE for low deck ... MORE from the ROCKET SCIENTISTS at MP ...
Posted By: polkat

Re: 451 stroker cam/rod clearance? - 07/16/09 06:55 PM

Allright, thanks guys! I won't worry about it. I also heard that sometimes the crank will hit the oil pickup tube boss, but that doesn't seem to be a problem with mine. Thanks again!
Posted By: Anonymous

Re: 451 stroker cam/rod clearance? - 07/16/09 07:51 PM

572 roller cam aluminum rods start looking you may have it close but most BME rods are "shaved" so you won't BUT cam must be degreed in to clear--if you are off by a little on a mock up well...they may be too close--check with a wire of known diameter--best way to check--degree most and they will clear--451 will never give you that problem--451 is the most under rated Mopar combo ever--I have made just crazy HP with one, sprayed the ever loving crud out of one , had customers ( 8secDart) go 8.50's with one and never ever had a problem with one--500 strokers break blocks, pull main webbs out by the root etc etc--a 400 block 451 is one of the all time easiest , best bob weight, fastest rev'ing, RPM dream machines you will ever build--a street 451 with a solid cam and aluminum heads will turn 7000 RPM and scare the pants off you and your passenger! and never give a minutes problem--they rev like a chainsaw!
Me likey! Can you tell? CHEAP EASY FUN--wait a minute I may have a new T shirt design! A back yard rookie can do one and they won't fail you! I like the long (440 length ) rod versions--the piston will slap but she will RUN BABY RUN !!!!!
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