Crank talk
- Thread starter cruzinbill
- Start date
No. The later cranks are fully counterbalanced on all locations and are not stamped, these are the 7M crank.
lol yah my eng was swapped sometime in the past it has a 6m stamped crank in it hmm wonder why tho to an older one my car is a 90
GrimJack said:Not to worry. The 6M version weighs less and can be revved higher.
Oh wise one tell us more...
seriously, how much lighter? stronger? weaker? Why higher revs, is it just the lighter weight? Love to know any info you might have on crank differences. :icon_conf
Actually, I don't really know that much about it. The rev limit was dropped with the heavier crank, but the reason behind it really is a guess on our part - more rotational mass means it't tougher to spin up and down in speed.
It should be several extra pounds, as the 7M has 2 extra counterweights.
It should be several extra pounds, as the 7M has 2 extra counterweights.
you know whats funny? my early 88 has a 7m crank in it.....and my rev limit is 7100 rpm....for some unknown reason?
I agree, I am about 97% sure the 6m crank weights in at 52 lbs and the 7m weights 57 lbs. Although, I have heard that the 7m, due to the extra counter weights, is better balanced. I run a 6m tho :icon_razz
eric
well im actually glad i have the 6m crank now since im building a hi reving application well now to get some rods and get the whole assembly balanced yessssss
it should still help being lighter, plus what is anyone 2 cents on knife edging the crank has any done it with this eng
It's been done, although rarely. If you are going to fully balance it, might as well do this as well.cruzinbill said:
While you are at it, think about adding a crank scraper as well...