thump

I have a CAI, exhaust and programmer.. Looking for a few more performance mods to gain HP short of dumping 3K+ into a supercharger.

For folks that have done underdrive pulleys and/or efans:
1) What brand would you recommend?
2) Did you see a noticeable gain (or any negative side effects)?

thump

bump.. no one running underdrives out there?

Keeblerz28

I have the Troyer e-fan kit that I bought from a member. Decent kit, although he said Troyer's way of mounting the fans on 'nails' really sucked, and he had a hole in his radiator after awhile. I made my own mounting brackets that hook onto the radiator top and bottom to avoid any problems. I could feel the difference after I installed it with the butt dyno. I think the Troyer kit has brackets now, so if you buy it new, you shouldnt have any issues. Luckythirteen has a writeup on making his own E-fan kit in the How-to section.

I am thinking about UD pulleys now too... Do I need any special tools other than a pulley puller?

azmidget91

i have both, it will gain a bit but just a little, id look for a used set of ud's and make your own fan kit, and dont use the rods through the radiator to mount it

Franchi

Pulley's do add power but not enough to where you really tell a difference in drivability. I have them on my Mustang and couldnt feel a difference in how it drove although dyno said it added 7 hp. For a baseline mod, I wouldn't recommend them, but if you are going to do an all out build, then yes they are good.

I would suggest looking into gears possibly. Those don't add actual power but the truck WILL feel faster as it ramps up thru thr rpms quicker.

Depending on how steep you go though, it will negatively affect gas mileages.

thump

Thanks all.. I'm wasn't expecting it would give me a ton, but for a relatively easy mod it seems like it may be worthwhile. Good idea about looking used.

Franchi - I'm currently running 4.56 yukon's with a Trutrac. I have 37' tires so it'll never feel like a racer, but every little bit helps.

I seriously considered doing an SC, but I just can't justify dumping another 3-5K into an '05 truck... I was also thinking about headers, but the install sounds like it's brutal.

ONELOWF

I have had these fans on for four years, and they work great.
http://www.summitracing.com/parts/DER-16516/

You can use plastic "nails" instead...Hayden fan mounting kit.

The Derale probe controllers are garbage. I went through several. I use a Spal dual fan controller, works well.

thump

Thanks, ONELOWF. I'll check those out.

azmidget91

i dont even use a controller, i have a little relay setup i did that turns one on with the ac and the other useing a probe thermometer thingy from autozone

BigRedXlt

So you guys are running dual 16" fans? What is the difference between a controller and the thermostat that comes on the fans from derale?