Question about 258 crank for comanche stroker

[SGTJHALL]

I'm having problems finding a 258 crank and from what I understand is that the Cherokee had the crank needed all the way up to 1990, so my questions are as listed

 

Do all jeep cherokees up to 1990 have the 258 crank in them?

 

I heard the cranks out of 87-90 cherokees don't require the snout to be trimmed for fitment into a later model motor, is this true?

 

I also heard the cranks out of the 87-90 with the snout trimmed already have a different weight and does this matter when doing a stroke on a 4.0.

 

I have a few junkyards around me with some 87-90 cherokees but nothing earlier that might have a 258 crankshaft, and this is one of the last parts I need to figure out before I can start my stroker build on my comanche.

[reece146]

XJ Cherokees never had a 258 crank.

 

I don't know where you got your information but I would not trust that source with anything as potentially convoluted as building a stroker and sourcing parts.

[SGTJHALL]

Ok so what is the latest year vehicle I can get this crank out of and what models?

[SGTJHALL]

The 258 (4.2) crankshafts we use as the basis of most of our stroker builds can be found in two basic forms, twelve or four counterweights. The heavier 66 lb., 12 counterweight, with it’s 64mm nose, was in use from 1971 to 1981 and the lighter, 46 lbs., four counterweight crankshafts, in use from 1982 through 1990. This four-counterweight crankshaft can be found in early form with a 64mm nose or in the later 54 mm nose. Both 258 crankshafts use a 3.895" stroke. Many feel the 12-counterweight design is the stronger of the two.

 

All 4.0L crankshafts utilize the same main journal and rod journal sizes as the AMC crankshafts. All 4.0L

Crankshafts are nodular iron, use only 8 counterweights and have the 54mm nose. The stroke in the 4.0L engine is 3.44".

---------------------------------------------------------------------------------------------------------------------------

Year_____Crank Casting No._Part No.

1971_____3199738________4488665 For Borg Warner automatic, small pilot

1972-74__3214723________8120508 12 counterweights, 66lb, 64mm nose

1975-79__3214723________8125450 12 counterweights, 66lb, 64mm nose

1980_____3214723________8132619 12 counterweights, 66lb, 64mm nose

1981-86__3235477________3235444 4 counterweights, 46lb, 64mm nose

1987-90__3727___________53005535 4 counterweights, 46lb, 54mm nose

 

258 block casting numbers

70-'72: 3199962

'73-'74: 3218618, 3222380, 3213867

'75-'79: 3227445, 3224098

'80: 3235077

'81-'89: 3235444

[wallisek]

Jeepstrokers.com forum is a great resource, enough information to make your head spin.

 

Sgt beat me to it on the crank info. :D

[jimoshel]

I'm having problems finding a 258 crank and from what I understand is that the Cherokee had the crank needed all the way up to 1990, so my questions are as listed

 

Do all jeep cherokees up to 1990 have the 258 crank in them?

 

I heard the cranks out of 87-90 cherokees don't require the snout to be trimmed for fitment into a later model motor, is this true?

 

I also heard the cranks out of the 87-90 with the snout trimmed already have a different weight and does this matter when doing a stroke on a 4.0.

 

I have a few junkyards around me with some 87-90 cherokees but nothing earlier that might have a 258 crankshaft, and this is one of the last parts I need to figure out before I can start my stroker build on my comanche.

 

 

 

Don't forget that there were two different Cherokees'. The FSJ and the later Cherokee XJ. I'm not sure of the years involved. Only the FSJ had the 258. I have several 258 but shipping would be the killer.

[SGTJHALL]

Comanche Addict:

 

How much are you looking to get for one of your 258 crankshafts? I might have to spend the money because I can't seem to locate one in my area and they have been really pricey on ebay of late.