Few questions
 

Ok, you guys are a lot more savvy than a lot of people so I'm curious what you guys think. What are your thoughts on underdrive pulleys and the material they're made out of for a street/strip build? I've seen aluminum, steel, and iron pulleys. Also, I've seen 50% for and 50% against running an electric water pump. I'd like to free up a little more hp.

as for an electric water pump, at least on an LSx based motor, i say do it. I have one in the SS and will soon be swapping it into the V. Just make sure all connections are done right, solid, and with proper size relays and wiring. I did it to free up as much little hp i could find.

as for underdrive pulleys, i never got into those. I never found a solid argument for them. It was always so mixed it seemed it didnt really matter and then paired with complaints of charging issues, and then possibly having to get a new alt pulley, just wasnt worth the trouble imo. Id rather take the money id spend on that and put it towards another bolt on, or a higher quality bolt on than i would have bought, to see additional power gains from there.

And on a side note, do NOT ever get a professional products balancer(or anything by them for that matter)... sure some people may have good luck with them, but my "SFI" one got tore up in less than 500 miles on my brand new motor.
http://i32.photobucket.com/albums/d5...S/balancer.jpg
http://i32.photobucket.com/albums/d5...ancer2part.jpg

EWP yes, UD pulley no

Steve - I ran underdrive pulleys on a Sonoma for years without any issues with belt wear or otherwise. With very minimal HP increase felt from the change. I did it after a chip, cold air intake, TB spacer, and exhaust. If you are looking at more HP then the electric water pump is the way to go. I've read that they have better flow than a belt driven water pump and are just as reliable as long as they are from a quality manufacturer and all connections are made correctly.

I like the EWP, but I had issues with my first one not always running (turned out to be a faulty relay), so I added a small LED so I can see the pump is getting power/running.

Personally, I've never really seen the UDPs make a big difference, and you need the full set so the Alt. works properly ( I'm talking from my expereince with LT1s, I can only assume LS1s would be the same?) So for the cost I'd use the money for a different mod.

My .02

yes i said this many times. For the cost of the pulleys vs the gain you get out of them, its not worth it I think. Unless you have done every bolt-on you can possibly think of, and have 100-150 bucks burning a hole in your pocket, I would do something else.

Did that happen at Island? I think Melissa and I were on the starting line when that happened.


So the overall consensus is that UDs are not worth it? I see manufacturer's claims of 8-12 RWHP but no actual dyno results to prove it from anyone.

Same thing for an EWP. I see claims of 11-25 RWHP but not much to back it up. I do hear a lot of people that like them though. One complaint I hear is that with a high volume pump like a 55gph Meziere there tends to be an issue with some cars with too much back pressure in the system and people have to remove their thermostats. Anyone hear about that?

no, do not remove your thermostat

The UDP on my G8 was worth 7 rwhp on a dynojet.

Yup. Do not remove your thermostat. You can drill some holes in it, or "gut" it, but do not remove it entirely.

I like both the EWP and UD pulley. The EWP did not make any noticeable difference, but it is nice to have the option to run it with the car off. I wouldnt pay more than 400 bucks if your looking at getting an EWP. The UD pulley made the car rev up faster, idk if power was gained from it. Its an ASP 15%, aluminum.

Both these together do come with a price, with just bolt ons and the stock idle, I was having charging issues where the battery would dip low at idle. I now have the idle rpm raised for the cam and all the charging issues are gone.

I see the EWP as a convenience and the UD pulley as a performance mod.

If I do UDs I'll leave the alt pulley off. I hear people have had charging issues at idle with it. What about damper vs piggy back?

Here's another question, what about a kick out oil pan and a windage tray? I hear the tray alone is worth 15hp and the pan will reduce oil temps.

For the thermostat issue with the high flow EWPs, I found a place that makes high flow thermostats for those pumps.

I was thinking about doing cams but the cost is pretty high for the hp/money ratio.

I've had a slp up for about a year now and have no complaints. If you check tech sponsors always have them on sale. Once installed the car did rev quicker which I liked. Only did the under drive and didn't bother changing the alternator pulley. No charging issues since I don't have a system and car is just bolt ons. I would definately agree with kirk evil.