I noticed while pricing out some parts on Rockauto today that they list a different alternator for the ITR. Checking the Acura fiche I see that the ITR had a Mitsubishi unit while the other trims all shared the same Denso unit. Both appear to be typical 90A units. Aside from the ITR's alternator being from a different manufacturer, are there any differences in fitment (pulley size maybe?) or can I grab whichever one is cheapest?

 

I've ran both units in mine with no issues.

I believe the Mitsu is a bit different inside to compensate for the slightly higher RPM's, but that's just what I heard in passing, so don't quote me on it.

 

Thanks. I figured that was the case, didn't want to get one and find out I need a new bracket or something weird.

 

Was always under the impression the itr alternator was different to all other integras due to the higher rpm. Have always rebuilt my alternator to ensure its the right one going back in.

 

Does anyone know if the shift width where the pulley goes varies between models?

Asking because I'm JRSC and I had to specify when ordering an aftermarket pulley.

 

Yes, from my reading, the shafts are in fact different sizes.

I don't think that the argument for the different alternator due to higher revs holds a ton of water. The ITR crank pulley is smaller than the GS-R (which I believe is smaller than the LS, but don't quote me), so the alternator is already underdriven compared to the C1. Also, there are several examples of Honda using multiple suppliers for alternators and/or AC compressors, even within the same model/trim level.

Fact is, only they know why they are different.

If I pick one up I'll probably just get the Denso. It's not even going on an R, I just so happen to have a Mitsu on there because I stole it from my dormant race car project for which I bought it used from an R swapper.