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Mr Rose · 06-11-2001, 09:48 PM

I take my Pulley knowledge from the V-8 world of F-bodies, and Stangs. All I can say is that for a 3 pulley kit on most any Production V-8 that I have ever seen, the pulleys on 281cid and up, only netted about 8hp(flywheel), and about a .15sec., 1.5mpg increase 1/4mile wise
. Besides, you can not run a race pulley with N02, or any kind of forced induction. This set up can and will cause main bearing cap failure. Literally spinning the crank past revolution tolerences.
Most Cranks are run to very pricise balanced tolerences. I would promote NISSAN to be very precisely balanced. However even a world wide automanufacturer adds a harmonic balancer to keep the chances of rotational tolerences in check.
Cranks flex, It's a fact. How much they flex, and what harmonic distortion is given off, is what needs to be in check.
FORD and Chevy both have put out Service bulletins on aftermarket crank pullies: "Block failure in conjunction with aftermarket UNBALANCED/UNDAMPENED crank pulley."

Mr. Rose: ANTI PULLEY
No thanks, stock is fine.

06-11-2001, 09:48 PM	#5
Mr Rose Join Date: Jun 2001 Posts: 47 Trader Rating: (0)	I take my Pulley knowledge from the V-8 world of F-bodies, and Stangs. All I can say is that for a 3 pulley kit on most any Production V-8 that I have ever seen, the pulleys on 281cid and up, only netted about 8hp(flywheel), and about a .15sec., 1.5mpg increase 1/4mile wise . Besides, you can not run a race pulley with N02, or any kind of forced induction. This set up can and will cause main bearing cap failure. Literally spinning the crank past revolution tolerences. Most Cranks are run to very pricise balanced tolerences. I would promote NISSAN to be very precisely balanced. However even a world wide automanufacturer adds a harmonic balancer to keep the chances of rotational tolerences in check. Cranks flex, It's a fact. How much they flex, and what harmonic distortion is given off, is what needs to be in check. FORD and Chevy both have put out Service bulletins on aftermarket crank pullies: "Block failure in conjunction with aftermarket UNBALANCED/UNDAMPENED crank pulley." Mr. Rose: ANTI PULLEY No thanks, stock is fine.