Moparts Tech Archive
BB Stroker Motor Q's & A'sOur member 451boy has a good article on the BB low deck stroker motor combo. One that has been kinda the base line combo for years.
Author Topic: 470 rod & crank recommendations
I'm interested in putting together a 470 using a forged 440 crank stroked to 3.90" in a 400 block. I would like to hear any recommendations or suggestion from those using either a 6.385" or 6.535" rod with the 2.2200 " journal and 0.990" pin such as if there are any advantage or disadvantage to using one or the other length rod and which off-the-shelf piston work well with this combination. Last, when preparing the crank, the Chevy width rods are narrower, therefore what is the proper way to have the crank prepped to accommodate the difference in rod/journal width and what clearance should I adhere too? Does any one routinely prepare these 3.90" cranks or should any competent crank shop be able to properly prepare this? My intentions are to keep this as a street motor running on pump gas. Thanks for your input.
I'd highly recommend the Manley rods which are 440 length and width but use the 2.200 and 0.990 pins.
This pic shows the internals of my 470 combo. More details in the article section at www.ARengineering.com
I'm running a C.A.T. rod, 6.385 long, with a Diamond flat top, 1.628 comp ht.
400 deck height 9.917*
BTW: Mine is for Drag Racing so I am not too concerned with the .050 side clearance on the rods.It will just toss around a little more oil.~Mike~
With all this 470 talk. What is the going price for the work on the crank. I have a std/std 440 crank and would like to make a 470 If the cost wasn't to high.
It cost me $250 for turning the mains and offset grinding the rod journals. I turned the counterweights myself in a CNC lathe.
Pricing? Good question but it seems to vary by region!
451 boy- if Moparts members send you their cranks, would you be able to perform the work? I have wanted to do the 470 combo for ages but, the crank shops in NY want way too much! And Todd440- how much for the Diamond pistons? Possibly using a set of NOS big block Chevy rods a friend will sell me CHEAP.
I can't see how it would make sense to send a crank across country twice just to be ground. There is no magic to it, crank grinders in NY operate the same as in OR.
The shop that does my stuff out here is a tiny hole in the wall this crankshafts piled up like cordwood. It is a dump. You would be embarrassed to ship a crank all the way from NY to this shop! I have to belive there is a shop just like it somewhere in Detroit, Buffalo, etc.
I called several machine shops in the area and they all use one crank grinder called Storm Crankshaft. The local shops quoted from $550.-700. I can ship it from my work for no charge and issue a call tag for pick up. Or if any of the guys reading this know of someone closer to me that would do the work reasonably. Taking the mains down is only $120., it is the offset grind that they want the big bucks for.
Some guys stroke to 3.915". I stopped at 3.900". I wanted to get rid of more of the groove Chrysler cut at the fillet area. 3.900' almost makes it. Just my opinion.