Under Drive Crank Pulley
I'm coming up on a big service I'm going to do and am considering some "while you're in there" upgrades if possible.
If anyone has, what benefits have you seen? Have you seen the benefits that they claim?
Also, does anyone have a video or instructions on doing this? Is this something I can do myself with basic tools or will the engine need to be out to do it?
Thanks in advance!
Oh, my! 10-20 hp for $550?
But, based on your comment, I don't know whether to pull the trigger or not. There is also a thread about the UPD offering having the OP have some sort of issue that puts him into weird shifting at 5th gear. BUT, other posters in that thread said that it worked awesome for them when installed.
So, I had hoped that given it's been some years since that thread there might be more users or at least some long term users of them who could chime in.
People who usually spend a lot of money on something that doesn't work are reluctant to admit it.
Last edited by JettaRed; Jan 4, 2024 at 10:15 AM.




stay away from VRP at all costs. Trash company, Trash people.
They're worth about 5-10rwhp but it's pretty hard to notice on a high HP engine.
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im surprised you run that given it robs boost from you and changes your pulley ratio. But yea those crank pulleys come with a damper plus the m157 are internally balanced not external where crank pulley weight and size are vital
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The perfect person to stumble upon my thread 🙏🏼.
So would you recommend trying one? I'm at ~715-725WHP (depending on Dyno) right now and want to go higher once you get your intake system to market. I'm looking to do mods that maintain the health and longevity of the engine, especially when I'm driving her hard or racing.
If you have any other recommendations that'd also be awesome, as I have a big service to do the rear main seal and turbo coolant lines + a bunch of other "while your in there's" coming up in the next 6-12 months.
You know I thought I had replied to your thread on your build with the questions I wanted to ask you and was wondering why I never had a response... Turns out my dumb*ss never sent the reply in the thread 🤦🏼.




So would you recommend trying one? I'm at ~715-725WHP (depending on Dyno) right now and want to go higher once you get your intake system to market. I'm looking to do mods that maintain the health and longevity of the engine, especially when I'm driving her hard or racing.
If you have any other recommendations that'd also be awesome, as I have a big service to do the rear main seal and turbo coolant lines + a bunch of other "while your in there's" coming up in the next 6-12 months.
honestly I haven't installed mine yet, my drivetrain and trans are shifting so insanely fast I figured the best way for me to see if the crank pulley has any gains/benefits in the rev/ or even just some improvements, I wanted to wait until I'm fully dialed in with a new tune that I rarely have time to work on. I haven't even done one pass in my car yet I've been so swamped at the shop. Sicksvt would have a better take on it . But my opinion is there's no reason not to try it . I'd definitely suggest doing some data and logs and perhaps post it on the thread. That way perhaps anyone on the fence can make an informed decision based off what you find.
Last edited by Cifdig; Jan 4, 2024 at 11:30 PM.
Second benefit is weight and looks, the billet pulley is lighter and looks prettier than the stock heavy cast pulley.
For only $400, I think it's worth it for a potential 5-10rwhp. Every little bit counts when you're trying to squeeze more horsepower.
Second benefit is weight and looks, the billet pulley is lighter and looks prettier than the stock heavy cast pulley.
For only $400, I think it's worth it for a potential 5-10rwhp. Every little bit counts when you're trying to squeeze more horsepower.
BY the way, where do you see it for $400 at? Lowest I found was $425 I think.




that's also the way I look at it, Id like to keep the car as health as she can be.
So I looked at it as:
1. Remove stress from accessories.
2. Weight savings (best and easiest way to go faster lol)
3. The claim of increased throttle response.
4. The claim of increased power.
Sounds like I should put in an order. Do you know if I can get this done myself without removing the engine? Someone in an old post said they got to it from below without a lift but it took awhile.
that's also the way I look at it, Id like to keep the car as health as she can be.
So I looked at it as:
1. Remove stress from accessories.
2. Weight savings (best and easiest way to go faster lol)
3. The claim of increased throttle response.
4. The claim of increased power.
Sounds like I should put in an order. Do you know if I can get this done myself without removing the engine? Someone in an old post said they got to it from below without a lift but it took awhile.





