Hi, folks. For those running a +2 ATI crank pulley, did you find it necessary to swap the alternator pulley to prevent it from overcharging due to increased RPMs? Thanks.

 

No.

+2% at 7000RPM would only be equivalent to 7140 RPM . . . not enough to worry about.

 

I didn’t notice any adverse effects.

 

Mini_Crazy, nice mods. Have you dynoed it? If so, please share.

 

It’s an alternator with a regulator ... rpm would not have an effect on ‘overcharging’ ... the battery and system will only draw as many amps, up to the capacity of the alternator, as it can use.


FWIW


Edit: Too LOWof RPM WILL Affect your output tho... which will not be the case with the OP’s situation.




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285HP@7500 RPM, with a very flat torque curve: more than 210 foot pounds from 3500 to 7000 RPM. Perfect for street, with the occasional track-day. In understated Brit-speak, acceleration is brisk.
With a different cam, 300HP is very doable, but it would cost me the low-end torque needed to survive occasional stop & go traffic on steep hills with a clutch.

 

Some input from someone with a less extreme setup. I have the the 2% overdrive version with a JCW 11% pulley. Idling is just that bit better and I believe the aircon works a little better when idling.

It's a quality part and highly recommended. A lot of money, but worth the upgrade for me. I received a faulty one first, but it was replaced immediately by the seller.

More pics in my build thread (see signature)

 

i have 17% SC and 2% crank, all good on my end.. no issues

 

We've installed hundreds of the 2% dampers and never needed to install a larger alternator pulley. The ECU controls the Alternator with regulator so it will automatically reduce the charge as necessary so you don't have to change the pulley or worry about overcharging.

It is also a great mod to add to a stock JCW to get just a little bump in power and keep it all JCW. I run this on my GP 1

We keep the 2% in stock too
https://www.waymotorworks.com/super-...ulley-r53.html

 

I picked up my ATI from you guys (standard diam) and was really surprised at how fast it arrived. Install happened in November... (iirc, its all a blur lol)

 

FWIW, due the minimum size of the hub, center, or what ever it’s called, the “standard” ATI is actually about .8% bigger than stock so your boost should also slightly increase with one. Not sure why they just don’t market them as 1% or 2%.