I have an M90 Eaton supercharger that was currently rebuilt. The guy that rebuilt my supercharger told me my supercharger had the wrong generation of rotors and he told me he put the correct set of rotors in
my rebuilt supercharger. My question is if he did this, would this
most likely have an impact on my air/fuel ratio? My truck seems to be
running lean so I have not been driving it at all. Please let me know what you think.

bixbystx

 

what's your A/F???

are you throwing any codes???

 

I remember a post after the rebuild you said you were making more boost than before, and I guess with the other rotors installed it could up the pressure and then throw the A/F off.. Who did the rebuild ?? and what was you boost at before and now after?

 

could be that pulley change you did a while back before you got your m90 rebuilt.
Check to see if your bypass valve is hooked up if its pluged or not working properly it will cause your engine to run lean because its not getting rid of your back pressure.

 

Did you get your problem fixed?

 

I'd like to hear his whole story on this. If he put a set of 4 lobe TVS rotors in that thing then you can expect problems. Sounds like an excuse to charge you more money.

 

The rotors on my supercharger had big gashes on them, they had to be replaced. I'm wondering if the new rotors are taking in more air and causing my air/fuel ratio to be different. I guess anything is possible. I'm still running the same pulley as I did before my rebuild. I'm running a 2.5 inch pulley which is suppose to give me around 9 pounds of boost. I was wondering what other things can cause a motor to run lean.

bixbystx

 

My truck still isn't running very well at all. I took it out tonight and it really ran well until it warmed up and then it started cutting out with a decent amount of peddle. I wasn't running WOT because if I'm lean I don't want to have to get mean with a new motor.

bixbystx

 

If your running lean you will pop a code. If your not popping a code there is something else wrong like you might have a vacume line hooked up in the wrong spot. This happend to me when my bypass valve line was hooked up to the wrong valve cover. Also if your pcv valve is bad or not connected you will get a very bad idle and cut out. hope this helps.

 

I think I found my problem last night with a vacuum line. It ran fine last night at WOT. Thank God.

 

Thats good to hear man im glad everything worked out for you in the end.

 

my air/fuel is around 11.6 at WOT, which is very safe as I'm told. I guess I could be a tad more leaner but it probably is fine just like it is.

bixbystx