Eaton M45 superchrager (Page 1/2)
sanderson231 JAN 06, 03:41 PM
Anyone know where to find a performance map for an Eaton M45 supercharger?

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formerly known as sanderson
1984 Quad 4
1886 SE 2.8L
1988 4.9L Cadillac
1988 3800 Supercharged

Larryinkc JAN 06, 04:53 PM
sanderson231 JAN 06, 06:17 PM
Thanks, that looks like a reasonable size for a 2.8L or 2.3L Quad 4

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formerly known as sanderson
1984 Quad 4
1886 SE 2.8L
1988 4.9L Cadillac
1988 3800 Supercharged

Larryinkc JAN 06, 10:22 PM
I have an MP45 on my 2.0l DD inline 4. It's been on the motor for a little over 210,000 miles, rebuilt once at about 70,000 miles. It is great on the 2 liter, makes it way more fun to drive, but for a 2.8l the MP62 might work out better.
sanderson231 JAN 06, 11:34 PM

quote
Originally posted by Larryinkc:

I have an MP45 on my 2.0l DD inline 4. It's been on the motor for a little over 210,000 miles, rebuilt once at about 70,000 miles. It is great on the 2 liter, makes it way more fun to drive, but for a 2.8l the MP62 might work out better.



I found an error in my spreadsheet so agree that the M45 is a bit on the small side. A 2.8L @ 5500 rpm with 7 psi of boost requires about 500 m3/hr of inlet air flow assuming a volumetric efficiency of 90%. The M45 can do this but the efficiency is only about 57% which makes for a higher discharge temperature. The M62 would get the flow back closer to the best efficiency point and keep the discharge temperature down.

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formerly known as sanderson
1984 Quad 4
1886 SE 2.8L
1988 4.9L Cadillac
1988 3800 Supercharged

sanderson231 JAN 08, 11:35 PM
Can a stock 2.8L V-6 handle 7 psi of boost with 100 'F MAT (intercooler) and 94 octane pump gas?

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formerly known as sanderson
1984 Quad 4
1886 SE 2.8L
1988 4.9L Cadillac
1988 3800 Supercharged

pmbrunelle JAN 10, 06:13 PM
Honest Don's 2.8 Fiero has been running at 16 psi (turbo):
https://www.fiero.nl/forum/...HTML/144739.html#p15

My low-compression 3.1 (mostly the same as a stock 2.8) Fiero has been hitting 15 psi (also turbo) non-intercooled at the end of last year on 91 AKI pump gas.

Depends also which 2.8 you're talking about. I think that 1988 Fiero 2.8s have improvements to their lubrication system, but I don't know the specifics.

[This message has been edited by pmbrunelle (edited 01-10-2023).]

sanderson231 JAN 10, 07:25 PM

quote
Originally posted by pmbrunelle:

Depends also which 2.8 you're talking about. I think that 1988 Fiero 2.8s have improvements to their lubrication system, but I don't know the specifics.




I my case it's a stock 1986 2.8L V-6 with about 110,000 miles on it. I'm still toying with the idea of an electric supercharger. I have found a 7.6 kW brushless electric motor. I could install a junkyard Eaton M62 in the trunk and provide at least 7 psi of boost from 0 to 5500 rpm. This motor and M62 might even do 10 lbs. I looked at a bin file for a 2.8L and could not believe how crappy the volumetric efficiencies numbers were - 70.3% max VE - that's ugly.

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formerly known as sanderson
1984 Quad 4
1886 SE 2.8L
1988 4.9L Cadillac
1988 3800 Supercharged

Notorio JAN 11, 12:06 AM
Larry, could you please explain how to read that interesting-looking map? And use small words so I will understand
Larryinkc JAN 11, 09:15 AM
I would if I could, all I know about it is in my case a higher number on the boost gauge means more fun.