underdrive crank pulley - Ranger-Forums - The Ultimate Ford Ranger Resource

2.9L & 3.0L V6 Tech General discussion of 2.9L and 3.0L V6 Ford Ranger engines.

LinkBack Thread Tools Search this Thread
Old 10-23-2014
zbott93's Avatar
Thread Starter
Join Date: Oct 2014
Location: College ststion, Tx
Posts: 9
underdrive crank pulley

Where can i buy an underdrive crank pulley? I know DZK used to sell them but I can't find one of those. Where else can I get one? and are they worth the money
Reply With Quote
Old 10-23-2014
RF Veteran
iTrader: (1)
Join Date: Jan 2014
Location: Vancouver, BC
Posts: 7,582
On a 3.0l, no, really not worth it, even on a stock V8 it would be marginal.

Underdrive pulley will free up some horse power, about 3%, probably closer to 2% under 250HP
On a stock 5.0l V8 that would be about 7HP, 220hp x .03 = 6.6hp
On your 3.0l rated at 180HP it would be 5.4HP

The claims of 10 and up HP increase are true but for higher HP engines, it is a percentage, not a straight increase
350hp x .03 = 10.5hp

The downside is alternator pulley may need to be changed if you do alot of idling, i.e. stop and go traffic.
And power steering might not work well under 1,000rpms, i.e. parking lots.

Electric cooling fan might be a better start, it frees up a few HPs with no real down side, except cost, but undersize pulleys are not cheap either.

Look at summit racing they have a large selection of underdrive pulleys
Reply With Quote
Old 10-24-2014
veNom_bz's Avatar
Join Date: Jan 2009
Location: Belmopan, Cayo
Posts: 57
$100 plus a belt

They are worth the money. Perhaps not from a peak horsepower perspective. In terms of responsiveness and general change in nature of the engine underdrive crank pulley is one of the best budget mods I've experienced and I've done a few.

This is what I wound up with in NA trim (comprised of throttle body, maf, intake manifolds, under drive pulley and custom sct flash). All induction noise, stock exhaust.

I suspect an auto would lessen your experience with under drive pulleys (I don't know that for sure).

In that case perhaps you're better off in first investing in a flash tuner (sct or the like).
Reply With Quote
Old 10-25-2014
RLong31's Avatar
The Ban Hammer
iTrader: (5)
Join Date: Jul 2009
Location: Monrovia, IN
Posts: 2,629
I bought mine (for 4.0L) from Underdog (no longer in business if I recall correctly). I also installed a Taurus E-fan. With either one you MIGHT notice minimal gains in responsiveness but it's nothing substantial. I ended up developing a bad belt squeal and removed the e-fan and went back to the stock fan. Either way I went with the under drive pulley because my stock crank pulley had this metal ring thing separate inside and rattle a lot, so I figured while I was replacing it I might as well try out the underdrive pulley for not too much more at the time. Can't recommend it, because it's not a significant enough gain, but it definitely won't hurt if you need one to try it.
Reply With Quote
Old 10-27-2014
iTrader: (2)
Join Date: May 2014
Location: Lake Mary, Florida
Posts: 349
How does a belt squeal tie in with the E-fan? Puzzled as to why you removed the e-fan because you developed a belt squeal.
Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Underdrive crank pulley zbott93 General Ford Discussion 1 10-24-2014 02:50 PM
Underdrive crank pulley - power results wydopnthrtl 4.0L OHV & SOHC V6 Tech 88 10-06-2010 03:18 PM
Those of you thinking about doing crank underdrive pulley eddiefromcali 2.9L & 3.0L V6 Tech 26 10-22-2009 06:27 PM
3.0L Underdrive Crank Pulley + O/D Alt Pulley & Belt Goodysgotacuda Engine & Drivetrain 6 05-17-2009 01:58 AM
Crank, crank, crank xXcecinestpasXx86 General Technical & Electrical 7 05-08-2009 11:35 AM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -6. The time now is 01:13 PM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.