Porting & Polishing Gen III Blower

Karma has a wife that can run a lathe?

All done with the porting. I plan on buying some new short bolts, but for now they will stay blocking 1mm of air in the blower.
here are some final shots:


I went with a gloss black, and plan on doing the snout some other time too. didnt come out perfect, but for the time i put into the prep and paint it came out pretty well. next time i'd strip it and prime it for better coverage.

I think you did pretty well for a home port job. Good work.

thanks! the blower seems to feel cooler to the touch with the car at operating temp. I dont notice a difference in sound, but the car seems to pull easier, especially for 80* weather.

Codith, Is this CNC work or home tools?

Looks like it. I would be really impressed if someone could knock out the "H" and open up the triangle so cleanly with hand tools.

I'm still looking for a housing to try porting. My idea (not really MY idea, saw somebody on the Grand Prix forums do it) is to create a block off plate that covers the whole rectangle. This way I could still keep a clean triangle and not have to worry about any JB weld falling out of the ports if I filled them that way. I hope this makes sense.

Weird that this came back from the dead... I pulled my blower off and started (further) porting it today. So far I have the triangle smoothed out, and most of that bar taken out. I'm using a dremel with various bits. I will be posting pictures! I will also be doing what Matt said about making a block off plate.

Here's that thread I was talking about:

http://www.grandprixforums.net/threads/65065-Safely-Filling-Silencer-Holes-on-ported-Eaton-M90-Gen-III-Supercharger-with-(PICS)?highlight=port

I believe Karma does something similar.

charlieRobinson wrote:

Codith, Is this CNC work or home tools?

That's CNC.   

Gen V's are getting cheaper and cheaper (so I hear), so depending on the time invested I wonder if it just makes more sense to look at a V these days than putting the time into porting a Gen III? ...unless of course you just want to do it youself for essentially $0 and your own time.

The limited research I've done seems to indicate that the Gen V flows equiv to a ported Gen III, and also runs a bit cooler (seems like a big plus). And also that there is no addtional benefit to porting a Gen V as it seems Eaton got the most out of the M90 by the Gen V.

Not sure I am 100% correct on all points, but that's what I've read.

Al

Porting a III is a better option in my mind because I like the added noise and the ability to drop a pulley size or two. When you price it out it's about 1/4 the price to do a Gen III and LIM (prices include new gaskets, dremel bits, etc.) vs buying a Gen V, LIM, gaskets, and messing with the vacuum lines and what not. Overall, you really want a fully P&P Gen V but there's a lot of compromises for price vs performance.

I finished my port/silencer block off today. Tomorrow I will get everything smoothed out and post pictures!

matt270avian wrote:

Here's that thread I was talking about:

http://www.grandprixforums.net/threads/65065-Safely-Filling-Silencer-Holes-on-ported-Eaton-M90-Gen-III-Supercharger-with-(PICS)?highlight=port

I believe Karma does something similar.

ugh, please don't compare me to the hack job in that thread.   (I guess you work with what you got.)
And I first did it 2 years before that thread was even created.   

I do things like this:

and this:

and thermal coatings:


and other fun things.

Your blower jobs are works of art, Karma

Karma wrote:

ugh, please don't compare me to the hack job in that thread.

I wasn't saying your QUALITY was of his. It's so far beyond what even professional companies will do for you. I'm just saying you made a plate to match the outlet so that the danger of anything going into the engine is next to nothing.

How do you do your coatings by the way?

matt270avian wrote:

Karma wrote:

ugh, please don't compare me to the hack job in that thread.

I wasn't saying your QUALITY was of his. It's so far beyond what even professional companies will do for you. I'm just saying you made a plate to match the outlet so that the danger of anything going into the engine is next to nothing.

How do you do your coatings by the way?

Coatings are from Tech Line Coatings, I use their thermal barrier on the inlet and outlet, and their DFL on the bores. Both get baked on.

Got my blower on the car last night.

To anyone who is considering plugging the silencer ports just for the added noise, I would say it's not really worth it. The blower whine is louder, but not considerably. Like, I thought it sounded a bit louder, but none of my friends said they could notice a real difference.

Sir Psycho Sexy wrote:

Got my blower on the car last night.

To anyone who is considering plugging the silencer ports just for the added noise, I would say it's not really worth it. The blower whine is louder, but not considerably. Like, I thought it sounded a bit louder, but none of my friends said they could notice a real difference.

Don't forget Eaton themselves claim it improves efficiency to plug them. They're just there to meet OEM specs. It also apparently helps with heat.

I've heard both ways. I've heard that it hurts and that it helps, so I don't really know. I doubt it's significant either way though

matt270avian wrote:

Sir Psycho Sexy wrote:

Got my blower on the car last night.

To anyone who is considering plugging the silencer ports just for the added noise, I would say it's not really worth it. The blower whine is louder, but not considerably. Like, I thought it sounded a bit louder, but none of my friends said they could notice a real difference.

Don't forget Eaton themselves claim it improves efficiency to plug them. They're just there to meet OEM specs. It also apparently helps with heat.

I think I read somewhere that Karma said this too, but I could not find anything on the web that comes from Eaton saying the same. Can you find anything?


Conversely, Turbo Tim @ ZZP told me it hurts efficiency and best to just leave the ports open.

charlieRobinson wrote:

matt270avian wrote:

Sir Psycho Sexy wrote:

Got my blower on the car last night.

To anyone who is considering plugging the silencer ports just for the added noise, I would say it's not really worth it. The blower whine is louder, but not considerably. Like, I thought it sounded a bit louder, but none of my friends said they could notice a real difference.

Don't forget Eaton themselves claim it improves efficiency to plug them. They're just there to meet OEM specs. It also apparently helps with heat.

I think I read somewhere that Karma said this too, but I could not find anything on the web that comes from Eaton saying the same. Can you find anything?


Conversely, Turbo Tim @ ZZP told me it hurts efficiency and best to just leave the ports open.

It was on the Eaton online forums that an Eaton rep popped on and said that, dunno if the thread still exists as it was many many years ago. But they stressed that it should never be welded(bore distortion), or just dabbed with JBweld.(it can come loose)  They said they were ONLY there for OEM sound control when the rotor pulse waves bounce back from the LIM.  Since it introduces a controlled air leak at a brief point in the rotor timing cycle with the holes, you do lose a little efficiency in stock form.  Plugging them properly gets that back and reduces temps very slightly since its no longer a hot spot/air shear.  You will notice that aftermarket castings of Eaton blowers didn't have("Had" because I believe most have moved onto the TVS design now which is wayyy different.) the air leak ports.(Magnum Powers, Magnuson, etc.)  

If you can do it right, sure plug them. If you want max effort, sure plug them.  If you want the sound, sure plug them.  But there is a good argument to be made that any gains are not worth the effort.  The little m62 needs all the help it can get for heat. the gen 3 m90, not as much.  And you will notice that by nature of the design differences in the air leak holes between them(thin slits on G3 m90, vs large ovals on m62), the increase in scream will be much less on the gen 3 m90.  The genV, well you can do it for fun(its holes are oval like the m62 since it wines more by nature than the g3 m90.) but you will get more sound difference by pulley-ing down in a performance build.

So:
m62 - needs the help and will make a noticeable diff in scream
G3 M90 - much less room for improvement and as a result won't scream much more after doing
GV M90 - doesn't really need the help, should be noticeably louder due to design diff, might as well for max effort, if you are doing this you better be dropping pulley anyway
* - proper plugging is not bad, aftermarket castings didn't have the holes since OEM sound was not an issue. (early gens did. last gens didn't)



*Edit* More fun from Eaton's Dev Chief Mike Sitar:
"Backflow is the method of compression within a Roots device. Air enters the inlet port, gets closed off by the rotor faces, then transfers to the outlet at inlet pressure. As it hits the outlet port, if you didn't have backflow slots, the air would immediately rush backwards, through the outlet port, to bring that cavity up to outlet pressure, then the rotors would come into mesh and force the air back the other way, through the outlet. That's a full, air flow reversal in the outlet port.

That reversal creates a high level of pulsation and noise. Backflow slots allow the air from the outlet to begin pressurizing that closed chamber before it moves to the outlet port. They allow air flow, into the supercharger, through those ports, then out the outlet port, maintaining one-way flow through two different ports. We took a percent, maybe a percent and half hit in adiabatic efficiency, but it, also, allows a one to three decibel decrease in noise. It does impact efficiency of the supercharger, but our biggest goal was noise reduction."

Flap wheels should here today/tomorrow. Gen V polishing will then commence.

yeeeeeah

Flap wheels aren't gonna cut it yo. Trust me, I've done it. I bought "flap wheels" for that purpose. I didn't even use them. Using those sanding wheels, you're going to sand ruts and grooves into the flat surfaces. You won't notice them until you get to the final polish. Then allllll the imperfections and dimples go HEELLLLOOOOO!!!!!!!

Just buy my already polished GenV   

Cool!  You're going to have fun!  The GenV is made out of a slightly different cast than the Gen 3, so you will notice its a bit denser, and takes a bit more to take material off.  That said, it can be made to have a *very* smooth finish. Just ask turtleman, his inlet was baby-butt smooth.

What are your plans for the outlet?

Edit... Are you doing the outside?(IE visual polish?) or inlet and outlet porting?  I assumed inlet and porting seeing what thread this is, but now Abaddon has me second guessing myself..

Abaddon wrote:

Flap wheels aren't gonna cut it yo. Trust me, I've done it. I bought "flap wheels" for that purpose. I didn't even use them. Using those sanding wheels, you're going to sand ruts and grooves into the flat surfaces. You won't notice them until you get to the final polish. Then allllll the imperfections and dimples go HEELLLLOOOOO!!!!!!!

Just buy my already polished GenV   

Pics of polished Gen V?