L83 Underdrive crank pulley installed!

8thsense · March 1, 2015

I put the under drive pulley on a couple weeks ago and was a pretty easy install. The new Under drive balancer was a lot smaller and little lighter than the stock unit. Engine revs quicker and mpg seem to be about 1.5-2 mpg better and seat of pants power also feels stronger. I always ran under drive pulleys on all my GM trucks in the past and had good results, so was happy to get the new L83 kit on.

Mike1220 · March 1, 2015

Got a link to this part? I've never heard of it but am open to anything that can help MPG

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bdbake01 · March 1, 2015

Any accessory issues thus far? AC, alt, etc?

8thsense · March 2, 2015

Any accessory issues thus far? AC, alt, etc?

No issues at all. AC and charging are normal, even at idle. Alt. charging was first thing I checked and did that by turning on lights, AC , etc and look for a charge drop at idle but all is good.

Here is a link.

http://www.amazon.com/UPD-Chevrolet-Truck-Underdrive-Pulley/dp/B00U4F1Y5G/ref=sr_1_1?ie=UTF8&qid=1425254472&sr=8-1&keywords=2014+GM+truck+underdrive+crank+pulley

TJay74 · March 2, 2015

I have ran UDP on all of my previous GM performance vehicles, always had great luck with them. How hard was the install? I still have the long bolt that I used to pull the new crank pulley onto the crank. In the past the UDP is usually good for 7-10rwhp or so.

bdbake01 · March 2, 2015

Wow. That's...that's...not cheap. Nope.

vettelovralexand · March 2, 2015

About as cheap as anything else that gains you an honest 5-10 hp. If you have the tools to do the work its an easy one.

Mike1220 · March 2, 2015

About as cheap as anything else that gains you an honest 5-10 hp. If you have the tools to do the work its an easy one.

What tools are necessary? Just curious. I'd be willing to drop the money for it if it will actually improve hp and hopefully MPG

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Spurshot · March 2, 2015

10% fuel economy boost. That's saying a lot.

07Softail · March 2, 2015

I have personally seen those installed and put on the rollers and haven't seen any claims close to those numbers. Although I did see improvement but no where close to 12-14 HP!!

RT

07Softail · March 2, 2015

I have personally seen those installed and put on the rollers and haven't seen any claims close to those numbers. Although I did see improvement but no where close to 12-14 HP!! And you can go to your local parts house and rent a balancer puller to do the job.

RT

07Softail · March 2, 2015

Edit: Double post!

RT

TJay74 · March 2, 2015

I have always used Powerbond UDP in the past. Install is not usually hard as long as you can get to the crank area. If you can get an 3/4 impact in there you can remove the TTY bolt pretty easy, then you just need to use a crank pulley removal tool to pull the old one off.

To put the new one on there is a little trick you can do with a butane torch. Heat up the center of the new pulley and then slide it onto the crank snout. You can also warm the pulley up in an over to 350° for about 30 minutes as well. I personally do the torch trick. Then use the original TTY bolt to 240ft/lbs to seat the pulley. Then remove that bolt and put in a new TTY bolt, seat it to the required ft/lbs. From there you have to turn the bolt some many degrees. I think it is something like 120° after you hit the torque setting. You will be lucky to get 70° from the ones I did in the past.

TJay74 · March 2, 2015

.

vettelovralexand · March 2, 2015

I dont buy a noticeable mpg increase but i do believe a 5-10 hp improvement at high rpm which is all you should expect. You need a damper puller and some way to reinstall the damper to do the job.