NFLblitze1

hey guys,

i have a really important question, being that the Unorthodox Crank Pulley claimed 20 lost horsepower top the engine on a V6 Accord. i am interested in getting it for the TL as some others on the forums had done. But what im worried about is, being that the new UR Crank Pulley will make the RPM's rise faster, does this affect the Automatic Shifting at all? or will it just automatically shift as it calculates...i don't want to screw up my car because of the ECU. any help would be great! thanks!

rbf351

the pulley doesn't make the crank turn any faster, all it does it make you accessories turn quicker. those are the AC, alternator and power steering. it has no effect on the engine speed

KJSmitty

Actually, to benefit from a different crank pulley you normally install a smaller pulley on the crank. The reason for this is it spins the accessories "slower" thus less HP is required/used for the accessories. Think of the smaller pulley being like first gear and a larger pulley being like third gear.. Takes less HP to start out in first than it would in third. Same principle.

The difference would not effect transmission operation at all.

NFLblitze1

thanks guys

SouthernBoy

I had a UR UDP (Unorthodox Racing Under Drive Pulley) on my 2002 Altima SE. I can show you dyno charts (not my car) where this pulley resulted in a gain to the drive wheels of 6.5 horsepower and 3 lb/ft of torque. You can "just" feel this.. as in barely.

I installed a two-pulley kit on my 1988 Mustang LX 302 and the result was 11 more wheel horsepower. That one was felt a little more from the small block Ford V8.

The one thing most people tend to worry about is the damping affect from the pulley being lost. I'm not sure if the crankshaft pulley on the TL is a harmonic balancer or not. If it is, do not install an under drive pulley that does not have crankshaft damping.

The UR pulley I put on my Altima SE was 15% smaller in diameter and weighed 21 ounces as opposed to 6.5 pounds with the stock pulley.

Be careful and do your homework before installing a pulley.

KJSmitty

Interesting,

Guess I never came across an engine that had the Harmonic Balancer and pulley as a single unit. Most engines with harmonic balancers/dampening devices have a removable drive pulley. Thus all you would change is the pulley which would have no effect on balance/dampening etc.

SouthernBoy

I agree with you and that has been my experience, too. That's the way it was on my Mustang.. separate belt drive pulley from the balancer. I seem to remember that BMW has the two components in one piece, but I'm not sure. I weighed the stock pulley I removed from my Altima and it was quite heavy. There was quite a discussion on the gearhead Altima site about pulleys and harmonics and whether or not the VQ engine was internally balanced (which people were saying).

What a lot of people don't realize is that you can do serious damage to your crankshaft bearings and piston/connecting rod parts (bearings, wrist pins, etc.) if you remove a pulley that also acts as a damper.

Until I learned a little more about how Honda set this up with our engines, I'd be reluctant to replace the stock pulley with an after-market unit.