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BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5646 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Blower
Posted by: BlownMGB-V8
Date: November 08, 2018 12:24PM

So I have a couple of 300's sitting around and I just ran across a deal on a used Eaton M112 and decided to buy it. As luck would have it, I also just had a pattern water jetted for port spacer plates so I ordered a pair in 1/2" thickness. A plan is taking shape.

This particular M112 is the Lightning version. It has a top inlet flange, is symmetric about the rear of the unit and hasn't much superfluous bulk but it does have a stiffening rib across the bottom between the discharge area and the bypass valve. This rib is below the mounting flange but can be raised even with it. So, what I'm thinking here is to finally reduce to practice my old concept of a lifter valley blower install. It can only go so low of course but once the blower comes in I can do an initial test fit and see what is possible.

But in essence, the blower will sit upside down in the lifter valley. The discharge port will be at the top into a plenum with straight vertical runners to the ports and injectors at the top. The inlet will be reconfigured to accept my existing inlet scoop with throttle body and filter element. A valley pan will seal the lifter valley and be part of the runner/plenum assembly, this probably means a removable plenum.

Using my inlet it will not fit under the hood nor is it expected to as it will be eventually finding its way into my own personal car which is by now quite well known for having a blower sticking through the hood and that won't change any time soon. But I expect measurements to show that with a rear inlet an under-hood installation will be possible.

The M112 and the Buick 300 complement each other very well, particularly the 2bbl 300 which has a factory CR of 9:1, and on this particular engine the iron heads are currently being retained which should give an engine weight of 485lbs counting the blower. With the alloy heads it would be 435lbs.

Sorry no photos yet, nothing really to take pictures of until the blower arrives.

Jim


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5646 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Blower
Posted by: BlownMGB-V8
Date: November 09, 2018 06:24PM

Here are a couple shots of the intake plates and lifter valley pan:

IMG_0004.JPG

IMG_0005.JPG

The blower should be here the first of the week.

Jim


Jim Stabe
Jim Stabe
San Diego, Ca
(681 posts)

Registered:
02/28/2009 10:01AM

Main British Car:
1966 MGB Roadster 350 LT1 Chevy

authors avatar
Re: Blower
Posted by: Jim Stabe
Date: November 10, 2018 09:06PM

Why don't you wait until you blow up your current engine before you start in on another one?


MGBV8
Carl Floyd
Kingsport, TN
(3496 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
79 MGB, Buick 215

authors avatar
Re: Blower
Posted by: MGBV8
Date: November 11, 2018 09:55AM

So he won't get bored. ;)


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5646 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Blower
Posted by: BlownMGB-V8
Date: November 11, 2018 12:02PM

Funny.
I can wait awhile, but this will fix a lot of issues and also let me try something I've been wanting to do for almost two decades now. But you are right Jim. I'm not going to blow up the 340, but it's a leaky engine and blocks my view, plus it has that low speed surge. So there are four reasons right there. I need to switch to either MLS or composition head gaskets, either should work fine (coolant leak) and the crank needs to come out and have the seal journal turned and polished (oil leak). I could remove the intercooler to lower the blower and clear my sight lines a bit, but that's as much work as doing a new blower install. Yep, I can tolerate the leaks for awhile and I can keep trying to look around the blower but neither is optimal. I have a habit of testing my limits to the extreme in both directions before settling somewhere in the middle and this is just another example of that.

Now compared to pulling the heads and crank and building a new blower installation, I can use the existing 50K mile 2bbl 300. Iron heads or alloy, I have both to use but simplest would be to use it as is with the iron. It just needs some new gaskets and the blower. So check out this photo for an idea of where this is going:

IMG_0009.JPG

In the meantime I have a controller upgrade to do, from MS2 to MS3 and I have some hope that this will cure the low speed surge issue. If it does, I may just put off the next swap for another year or so. After all, I can continue re-torquing the heads and the drip below can continue to rustproof the underbody as it has for so long now anyway. As for the view, well that demands great caution. It's like rolling the dice every time I go out.

Jim


Jim Stabe
Jim Stabe
San Diego, Ca
(681 posts)

Registered:
02/28/2009 10:01AM

Main British Car:
1966 MGB Roadster 350 LT1 Chevy

authors avatar
Re: Blower
Posted by: Jim Stabe
Date: November 11, 2018 12:07PM

Not only makes it lower but shorter as well. Might have an issue getting the valve covers to seal also :-)


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5646 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: Blower
Posted by: BlownMGB-V8
Date: November 11, 2018 12:19PM

Everybody's a comedian ;) That was just a conceptual mock-up for your benefit (well, everyone's that is to say). The blower will get a longer snout naturally, and will have to come up probably 1/4" from there. Good bit of machining and such to make it work but I think that's a good start.

I'm hoping that by starting the blower part I'll begin feeling a little more charitable towards the controller and its upgrade. Right now I'm pretty disgusted with it. That needs to change and the sooner the better. Can't enjoy the mind twisting electronics end of it in that mood.

Jim



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