Gents,
I found a pretty good deal for an eaton m112 from a 4.2 that is low mileage in good shape. I've read the available threads on the topic but the response varies from minorly noticeable to really nice improvement, especially on the top end.

My blower seems fine, maybe a little noisy despite a replaced coupler but nothing crazy.

Would you say for roughly $450 including gaskets and such, this is worth doing?

Thanks!

 

When my blower brokes up to unrepairable state I will switch to gen 5. Mainly only due to helix cut gears. I do have solid coupler what do increase blender sound and so great sound when in boost. But replacing working gen 4 to gen 5 is not really worth it.

 

You’ll have to drill and tap holes so the 4.0 TB elbow can be bolted on a later 4.2 blower.

 

TLDR it's not worth it. Also you absolutely need the gasket for the 4.2 blower to tb elbow, to space it out properly above the needle bearing caps, and maybe a bit of gasket maker around those to be safe due to the differences in elbow flange shape. There was no need to machine any mounting holes when I did mine, everything bolted right up.

I managed to score a gen v blower insanely cheap from the junkyard, with the intent to swap it in until I realized the amount of work needed to do so, and it sat for a few years. Eventually I rebuilt it (new needle bearings and front coupler, as well as a thorough cleaning) and swapped it in when my factory sc started to leak from the pulley seal and blew its coupler shortly after.
The silence from the helical cut gears is nice, the everpresent subtle mild hum of the straight cut gears is gone. It still makes supercharger noises under load as expected. That's really the only reason to swap it in, is the silence. I don't think it provides any meaningful improvements in power.

 

Interesting. From my reading they should be much more efficient but that seems not to be the case. I made an insultingly low offer and they took it so i guess i will be doing the swap. Can likely come close to breaking even if i sell the old one.

Thanks for the input

 

If they are a lot more efficient you might see some MPG improvement?

 

Good Morning

I just completed the SC overhaul/rebuild/upgrade last year. I spoke with all of those SC rebuild vendors for price and timeframe comparison.

they all say in stock form. Gen 5 may not have much or if any performance advantage over Gen4. so replacing a functional Gen 4 SC to a Gen5 is not really a performance upgrade.

if you want so serious upgrade, do the porting which I did.

 

I love the supercharger whine. Sticking with my gen 4 eaton!

 

I agree Brandon. At full tilt with my mods, the sound is intoxicating with a gen 4.

 

My understanding is that the original blower was a gen 3.

Either way, job is done. Had to trim the bypass hoses a touch but nothing hateful to get elbow to bolt up.

Blower whine is still there, so no issue there.
Havent had a great opportunity to test power but the car is fast regardless. Will update after some power evaluation.

This is with a 1.5lb upper and 4.2 (8% larger) lower, so not spinning the blower super hard.