You don't hear of too LT1s that have aftermarket underdrive pulleys? I know that every bit helps but is it worth it? At Summit BBK sells them for $75 and March is $105. How much horsepower would it free up on a H/C car like mine?
Thanks!

 

i have somekind of underdrive and sometimes have charging problems on short drives but i have a optima battery.. i dunno if this is hurting my horsepower due to undercharging

 

Thats what Ive been hearing is that the aftermartket pullies arent worth it $ to HP wise plus they cause problems with charging..

 

Ive had pullies on my car for 5 years. Never had a charge problem, never had any type of problem. Cost was probably 160 with the belt, it was worth it as i did notice a gain in hp.

 

What pullies do you run? How much HP did you notice?

 

pullies or PULLEY? i just have a crank underdrive

 

I had the BBK crank pulley and I recently (Last weekend) swapped back to stock because it had MAJOR charging problems. I was couldn't sit at idle with the Fan, AC, and blinker on without the volts getting LOW. The car even lost charge and wouldn't crank because it ran so low. With the stock pulley on, it hasnt had any charging problems whatsoever.

 

You don't hear of alot of LT1s running them because they are simply not a power effective mod for the money.

 

They cause charging problems, especially if you have an automatic. I sold mine. No noticable difference with or without them, except my charging problem is gone now.

 

Dyno showing 0.7 peak HP gain:

http://www.ws6.com/mod-2.htm

 

I think the "under the curve" gain is worth $75. Every bit helps. I have the BBK crank pulley. At idle in gear, the needle does dip, but not dangerously low in my car.

 

If you going to do it, you have to get the alt pulley as well! I have no charge problems.

In the study that was posted, it produced and average of 4.4hp and 5.8 tq.

 

I had the crank pulley back in '99 and I had charging problems.

I am about to buy a TPIS 2 pulley set and try again without the charging problems.

That WS6.com dyno was done like 8 years ago and everyone has been convinced that they do nothing since then. I don't buy it 100%. I watched Hot Rod TV where they put a 2 pulley set on an LT1 car a couple years ago. They dynoed right after they were installed and got about 8rwhp increase. Didn't take it seriously until I read an article in GM Hitech or something where they put some TPIS pulleys on an LT1 Camaro and dynoed like 8rwhp increase as well.

 

The ASP pulleys are some of the best ones.. A tad pricier but worth it.. If you need some pricing let us know.. we sell all the major brands just might not be on our site :-D

 

i think you might have had something wrong. i just put the tpis pulley's (two of them) on my car. i havent had it dyno'd to confirm the difference but SOTP feels a bit different. not alot and no one else but me could tell. it might have picked up a couple of horse at the wheels. what does seem different is the rev. it seems to flash a bit quicker.

i have no charging issues at all. the second pulley is on the alternator to keep it spinning at the same rpm but i think its too small. where i used to run at 14 ish V i am now at 15.5 to 16 ish V. i have done just about every other bolt on so the pulley was next. once i get the gtech and the drag radials back on it i can let you know if the 1/4 mile changed.

david