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HEMI Technical Info

Stroker (kits) - Chevy rods in a Dodge

This for Information Only
- there is advantages and disadvantages in using this information :
Basically the stroker kits available today (and older versions of this practice ),use a smaller diameter chevy rod bearing after offset grinding the rod journals of a stock (or stock style replacement ) crankshaft to achieve a longer stroke. You can also purchase new crankshafts with these dimensions.
Crankshaft Balance Factors         The long and short of it - Rod length Information

advantages

disadvantages
Cheaper than aftermarket crankshafts  
This is a way of resurrecting a badly damaged
but possibly very expensive used crankshaft		  
Lighter - revs higher Lighter - breaks easier

(note: I have always disputed this advantage because the
stock B/RB Blocks have a real problem here ,
the lifters are angled down , this geometry is corrected in
some aftermarket blocks )

Additional .050 side clearance on rods if the crank isn't first welded or rods custom made.
( note: new cranks can be made this way also )
The long and short of it:
Left - 500 ci - dodge based piston, rod and pin
Rod journal = 2.375"
Wrist Pin = 1.156" ( thick wall - Tapered )
Weight 2400 g
Note: this will survive a Top Fuel 4 sec pass
( although it usually bends the wrist pins )
and a 5 sec pass in a TAD , shifted at 10,700 rpm ?

Right : 527 ci - B block - Chevy rod
Rod journal = 2.2"
Wrist Pin = .990" ( thin wall )
Weight 1420 g

 

Left :
this appears to be a stock Hemi 8 bolt Mopar factory forged crankshaft that has been
1) ground down to "B" engine main journal diameter
2) offset ground to net a 4.375 "
3) then hand  ground to clear the pistons and the block
Note: The outside diameter of a Chrysler B crankshaft is 7.3", RB /Hemi is 7.4"

weld can still be seen here also after cutting from 440 to 400 journal size .125"

Edge of weld can still be seen after
cutting the crank down .175"

The crankshaft above appears to have been an original HEMI shaft because it has an 8 bolt flange. For that reason it has probably been repaired and abused many times over the last 40 years but
when resurrecting a badly damaged used crankshaft you have to make a decision as to when it is cost and time effective.

 

Crank
shaft  		Rod Journal Sizes Rod Width Journal Width Rod Length Rod Length
Ratio		 Main Journal Sizes Stroke Bore Bore Stroke Ratio counter
weight dia 		Wrist Pin Sizes
Race-hemi
500 Fuel
(small bore)		 2.375" 1.015" 2.060" 7.0"+ 1.55+ 2.750" / 3" 4.5 " 4.187" .93 7.4" +  1.156"
Race-hemi
500 Fuel		 2.375" 1.015" 2.060" 7.0"+ 1.6+ 2.750" / 3" 4.375" 4.25" .97 7.4" +  1.156"
Race-hemi
450 TAD		 2.375" 1.015" 2.060" 7.0"+   2.750" 4.1(+-) 4.38"
(+-)		 1.06 7.4" + 1.095"
Race-hemi
527 TAFC		 2.375" 1.015" 2.060" 7.0"+   2.750" 4.375
(+-)		 4.38
(+-)"		 1 7.4" + 1.095"
Race-hemi
572		 2.375" 1.015" 2.060"     2.750" / 3" 4.5 " 4.5" 1 7.4" + 1.095"
Race-hemi
604		 2.375" 1.015" 2.060"     2.750" / 3" 4.75 " 4.5" .947 7.4" + 1.095" / 1.156
Race-hemi
636		 2.375" 1.015" 2.060"     2.750" / 3" 5.0 " 4.5" .9 7.4" + 1.095" / 1.156
Dodge Hemi * 2.375" 1.015" 2.060" 6.860" 1.83 2.750" 3.750 " 4.250" 1.13 7.4" 1.0321"
Dodge RB-440 * 2.375" 1.015" 2.060" 6.768" 1.80 2.750" 3.750 " 4.320" 1.15 7.4" .991"
Dodge B-400 * 2.375" 1.015" 2.060" 6.358" 1.88 2.625" 3.380 " 4.340" 1.28 7.3" .991"
Chevy BB rods on aftermarket crank 2.20" .995" 2.009"     2.625"
/2.750" 		3.380 " /  max 4.75" 4.32+"   7.120 " +  
Chevy BB rods on reground stock 2.20" 1.015"
( ? )		 2.060"
( ? )		     2.625"
/2.750" 		3.380 " /  max 4.15"     ( ? )  
Chevy BB * 2.20" .995" 2.009" 6.865"   2.750"         .990"
Chevy SB - 400 * 2.10" .943"   6.865"   2.650"         .927"
Chevy SB - big * 2.10" .943"   6.865"   2.450"         .927"
Chevy SB - small * 2.00" .943"   6.865"   2.300"         .927"
* = stock Note after market rods may  have additional side clearance

Race - hemi/B/RB - not kits - varies from team to team
every part may be custom dimensions

 

Common Stroker
 Kit Dimensions		 Stroke Rod Length(s) Rod Journal Size Wrist pin Size Bore Oil Support Rings or Pin Buttons

440 Block

            
512 4.250" 7.100" 2.375" .991" 4.350" (.030)  
500 4.150" 6.760" 2.375" .991" 4.350" (.030)  
440 * 3.750" 6.760" 2.375" .991" 4.350" (.030)  
             

400 Block

            
512 Long Rod 4.250" 6.760" 2.20" .991" 4.375" (.030) yes
512 Short Rod 4.250" 6.535" 2.20" .991" 4.375" (.030)   
500 4.150" 6.760" 2.20" .991" 4.375" (.030) yes
470 Long Rod 3.915" 6.760" 2.20" .991" 4.375" (.030) yes
470 Short Rod 3.915" 6.535" 2.20" .991" 4.375" (.030)  
451 Long Rod (x) 3.750" 6.760" 2.375" .991" 4.375" (.030)  
451 Short Rod (x) 3.750" 6.535" 2.375" .991" 4.375" (.030)  
* = stock (x) = 440 crank ( mains cut down )      
Hemi- Block Race-not really a kit see chart above