Since the Malibu is down for a new engine, I thought that I would port the blower cases. Inlet has been opened up 5/16th inch and radiused inside. Outlet has been opened up 3/8th inch and bosses removed. Inlet before/after.

And outlet before/after.

Nice porting work, looks good. What kind of gains do you expect to see with the porting. I know you have the twin blowers but i havent followed your car that close.

So here goes

What's the reason behind opening them up? More flow? more boost? or both

Both...

Plus switching to 10% overdrive pulleys for even more fun.

BW

dude I am soo excited for you I soo wanna see what this will do

You ought to work out putting two throttle bodys before the blower then blow it straight into the manifold.

Unless you like 90 decible's...

I'm still impressed with how quiet mine is

I've got something up my sleeve... just not quite ready for prime time. BW

so or you porting them out as you see it, going off directions from a book/website, getting help from silverback, or what??

just curious..


btw, this may sound strange, but what if you mounted them backwards down low ( idonno if you have the room)..


if they were low and forward you could run them directly into a intercooler, and then into the TB.... plus nice cold intake air is right there....

That's a huge amount of material you have removed there. What did you use for the job, a die grinder?

I like the originality of your set-up. Looks good.

Robert

huh, I wonder if it's somethign like what my brother is considering for the LTD

Actually, I kinda doubt it... I think you've taken a more high tech aproach...

WRT to ideas... I think I did give him some clue what we did, but couldn't really supply pictures or anything of it. As far as what I'm seeing there was some improvement past roughly where that blower is at now by just taking more time radiusing the inside of the inlet...

I'm going to try and do that, but I have already popped thru the case so there isn't much left to work with. A little JB weld will fix the present holes, (no biggie as there isnt any boost there).

Rooster... yeah twin LS1 TB's ahead of the blowers.. and I may ditch the intercoolers.. haven't decided yet.

BW

just to let you know......you may lose a lot of boost depending on how good your intake/heads. You have to be careful that you dont spin the blower too fast and ruin the bearings

i think there good for 14000 to 16000rpm

Eaton lists a redline of 14,000 rpm...

83 Crossfire TA and bro have spun theirs to 18,000 and it seems to be holding up just fine.

With a 10% overdrive pulley I'll have a 2.64 to 1 ratio..

Shifting at 6800 spins the M90's to just under 18,000.

Vroom....

Block is a 3700010 4 bolt.
Crank is a 283 forged.
Rods are Carrillo 6" with Carr bolts.
Pistons are TRW 2441 .030.

The rest is under wraps...

I've seen a couple of cases that have had the ribbed areas in the back welded in or filled with epoxy (industrial JBweld works great, same stuff as the normal stuff but comes in bigger containers).

Different series cases are definitely different castings, with different webbing layouts and a different shape inside. I took a look at the one on the LTD today and noticed that the ribbing on it isn’t nearly as deep as what I’m seeing in your pictures and the intake mounting pad appears to be a little bigger.

And yea, we are spinning it to over 18K without any issues. You'll have problems with rotors expanding too much from the heat and contacting before the bearings go. FWIW, these things get more efficient as you spin them harder.

If you look at the pics at the top, the inlet one. I have come thru between the rear bearings and the bolt holes for the inlet, on either side of the rib. Since it's behind the rotors, filling it with JB weld from the outside shouldn't be a problem, no boost to worry about.

I wonder if putting a ceramic coating on the inside would have any benefits.. May have to check that out.

I noticed that Mike uses some butterfly bypasses between his TB's and inlets.. I'm assuming these open to the atmosphere under vacuum? I ran BOV's between the outlets and TB to release boost under light cruise and closed throttle, but Mike's setup has me a bit puzzled.. BW

edit: I found the bypass info. The bypass connects the inlet to the outlet under vacuum.

I have to find a picture… I’m pretty sure that the one on the LTD doesn’t even have ribbing there, just a solid pad.

Quote:

I wonder if putting a ceramic coating on the inside would have any benefits.. May have to check that out.

huh, maybe. Anything that tightens up clearances should make it more efficient as long as it doesn’t tighten them up too much. That was the idea behind the Teflon used on the later rotors. Really, heat reflective/insulative ceramic would also prevent the parts from absorbing as much heat which would cut down on the expansion of the parts as well as heat transfer to the air.

Quote:

I noticed that Mike uses some butterfly bypasses between his TB's and inlets.. I'm assuming these open to the atmosphere under vacuum? I ran BOV's between the outlets and TB to release boost under light cruise and closed throttle, but Mike's setup has me a bit puzzled.. BW

I haven’t looked at it in a long time to look how he did it, but they are a set of single bore ford TB’s that my brother and I found in the scrap yard (we’ve traded parts back and forth a few times. I have a set of turbos off of crazy joe’s TT mustang, there’s a set of his t-bird wheels floating around…). My brother’s car is running a modified version of the stock m90 butterfly bypass (bored larger and with a custom butterfly that eliminates the bleed slot) off of the thunderbird parts that is welded right into the inlet plumbing.