Summit Underdrive Pulleys
 

I know we've talked about this set in the 04-08 forum, just thought I'd "rate" them over here.

Put about 600 miles on them already (had a couple long trips Sunday and Tuesday). Fuel economy is up, not quite a whole mpg but I've only put a tank and 3/4 on them so far. Could be coincidence, could be the pulleys.

As for performance, I'd like to think I can tell a difference. Not sure how much you can "feel" 15hp on a 3500lb truck, but when I stomp the gas to pass someone on a 2 lane I feel like I get up to speed and around them a little quicker.

Install wasn't difficult, maybe I have a good taste in my mouth because I virtually did the install twice and the last time was a breeze.

Summit's kit takes the stock length belt, Goodyear's website has a part number cross reference tool, use that, find you a Gatorback at stock length and IGNORE summit's recommendations. They don't have a clue what belt goes on an 04 4.6L. They tried 3 times for me, wrong all 3 times.

Price was GREAT at $134.

Glad they are working out for you!

Now if I can find the time to put mine on! I know it won't be this weekend.

Lars

**UPDATE**

Have put about 800 miles on my truck with the pulleys, and between both city, rural, highway miles, I'm consistently getting 1-1.5 more Miles per gallon. Didn't really want to comment that early, could have been conditions, but 800 miles of an extra MPG+ I think speaks for itself.

Very pleased.

wow. so $134 for an extra 1-1.5 mpg's. this mod sounds like it WOULD actually pay for itself within our lifetime. lol. can you explain again on the how the power gains felt? and also which part number this is. i've been looking at troyer's pulleys but they are about $100 more than the summits.

Are they starting to run summer blend in your area?

Lars

Last time I asked my contacts at a couple gas stations no, not yet. I only put gas in my truck from the same Shell Station (unless I'm out of town of course).

I'll double check again tomorrow night at softball.

so are the power gains mostly in the upper rpm range? due to the fact that you can feel it while passing

Correct me guys if I'm wrong, but I'd say it's across the board. You're spinning less for the same speed.

Seeing your thread about underdrives reminded me I picked one up a couple of years ago @ a going out of business performance shop sale. I forgot I had it! :doh:

If anyone is interested I'll sell this one for what I paid. 85.00 bucks plus shipping.

http://inlinethumb38.webshots.com/41...600x600Q85.jpg

http://inlinethumb50.webshots.com/30...600x600Q85.jpg

http://inlinethumb22.webshots.com/43...600x600Q85.jpg

http://www.dougherbert.com/underdriv...t-p-25782.html

That's a STEAL! Wish you had found them before I bought mine! :)