M112 Dyno

kenewagner

Registered User
Took the car back to the dyno to see what kind of numbers it would produce. The car has had no modifacations other than the M112 blower. Hook up to the dyno we ran a couple of runs just to see what kind of boost it was producing. It ran about 19 to 20 lbs of boost with a 3.1 pulley. No evidence of belt slippage. Blower sounds a lot louder than the M90 it replaced. First few runs we had a problem with the tranny wanting to down shift. Remember that the last dyno I was told to mash the pedal in a smooth controlled manner. I was just flooring the pedal & it would kick down to second a few times. The tuner back out a lot of timing back to 19 degrees. Intake air temp was 71 degrees. Ran another run & blew out the passenger side head gasket at 4700 RPM. RWHP was 268 & Torque was 366 with out really get into the tuning part of the Dyno. The increase with out really tuning the engine was 30 RWHP & 16 RWTQ. It is a set back for me as I was looking for 300 RWHP which might have been there had we got the timing dialed in.

I want to thank the local guys for showing up & helping me. It was like a meet and all have volenteered to help replace my head gaskets to get it back up and running. My goal also was to give an apples to apples comparision of the M90 vs the M112. I will probably not be able to do that now. If I am going to be pulling the heads to replace gaskets than I am not going to bolt back on the stock heads. For me personally if the heads are off than its time to bolt some decent heads on remove the last restriction to the air flow. I am pleased that the blower itself performed flawlessly looks good and will be in place to produce numbers that I want down the road. I will continue to post any developments good or bad on the M112 as I run into them. I hope to have this all done in the next few months as I want to be driving this car in the spring and I will have the rest of the year to be putting together a short block for next winters project.

Ken
 
It's too bad that the HGs went yesterday, Ken. But I think that you can say that the M112 is an effecient mod for the SC. When we looked at your dyno last night, peak boost was at 19.2 lbs while underdriving the supercharger (compared to the stock drive ratio of the M90). By the way, was that with the largest pulley or the middle sized pulley you have? Don't get too discouraged about the HG though. We've got a few local guys who have changed them, so you'll have experience to help out when it comes to actually changing them. I'll do what I can to help, but you know my limitations.

Heads and cam are next on your list...
 
Sounds like your project is turning out nice, if you don't give up.
I am sure with new Coated Fel-pro permatorque MLS gaskets.
Part # left side 9662PT
Part# right side 9263PT
These gaskets will help .
Nice job you have done!

Randy
 
Sounds like your project is turning out nice, if you don't give up.
I am sure with new Coated Fel-pro permatorque MLS gaskets.
Part # left side 9662PT
Part# right side 9263PT
These gaskets will help .
Nice job you have done!

Randy

Thanks Randy, No plans to give up, just a bump in the road. Thanks for the part numbers, I will be doing studs as well. I will start tear down this weekend

Ken
 
Sorry to hear Ken.

30 HP JUST from a blower swap is nothing to skuff at. Thats very well done! The results will only be multiplied when you get a set of heads and a cam. :) I too once hoped for 300 HP with just 'bolt ons' and not having to go internal modifications, boy was I wrong. :p
 
Sorry to see that the HG blew Ken, but 30 HP from just bolting your blower is quite good especialy since it wasnt even tuned yet. Have you ever touched the HG's on your car before?

Were you able to get any A/F readings? If so what were they at?
 
Sorry to see that the HG blew Ken, but 30 HP from just bolting your blower is quite good especialy since it wasnt even tuned yet. Have you ever touched the HG's on your car before?

Were you able to get any A/F readings? If so what were they at?

The last run it started at 11.5 and steadly climbed to 13.0 & 4700 RPM where the gaskets died and untimely death. The advance was set back so hopefully we could dial more in each run and see what we could gain. Never really got more advance in so can only speculate what the number could have be.The car has 145,000 miles on it and as far as I can tell never had the gaskets changed. I will know that for sure hopefully when I pulled the heads. Andy shot some pictures and video and should be posting it soon

Ken
 
Ken,

Once you get some ported heads and a better cam installed, you'll be kicking yourself for not doing it sooner. The MLS gaskets and a set of APR studs will go along way towards improving your comfort level at those boost levels.

David
 
Did you run stock exhaust as well?

Those are good numbers and i'm sure that they would have been better if you would have got it to run right.

With some good heads and a good sized cam, there shouldn't be a reason why you couldn't reach 400rwhp.

BTW, where did you find those HG's?
 
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Ken,

Sorry to hear about the death of the headgasket. Looking foward to seeing some real numbers in the future. Seems once you get the tune straightened out your goal may not be far off. Are you getting enough fuel?
 
Did you run stock exhaust as well?

Those are good numbers and i'm sure that they would have been better if you would have got it to run right.

With some good heads and a good sized cam, there shouldn't be a reason why you couldn't reach 400rwhp.

My goal is to run 375 to 400 RWHP. I have put off the internals simply because the bolt ons are easy & cheap. I think a lot of guys like tom sc and myself will be kicking ourselfs when we see what a cam & heads will do. I dont have anything else to bolt on my engine. I think the only thing I havent got is underdrive pulleys. The Exhaust is headers, 21/2" mandrel bent down tubes, dual 21/2" in 3" out split to 21/2" dual in rear with 21/2" mufflers

Ken
 
.The car has 145,000 miles on it and as far as I can tell never had the gaskets changed.

Ken

I think you have some good numbers, with the miles on your motor.

I am sure you can get closer to 300 rwhp with freshined up
long block.

The addition of ported heads, cam, thats the easy ,lazy
track to 300rwhp.:)

Randy
 
I think the whole idea is bolt on as you go..Unless you can afford to have your car out of commision for awhile...

All of your boltons are things you would need later on to support your power level sans the need for larger injectors
 
If it is any condolence, it looked pretty cool when the HG's went on the dyno. Talk about a huge white cloud! :eek:

I'm pretty confident that you would have been in the 290-300rwhp range if we could of gotten everything tuned in. Dan hadn't even starting working with it yet. It looked like he just had the timing pulled back seeing where the fuel was at, so there was a lot of power left on the table. Those would of been some pretty impressive numbers on stock heads and cam.

Thomas
 
If it is any condolence, it looked pretty cool when the HG's went on the dyno. Talk about a huge white cloud! :eek:

I'm pretty confident that you would have been in the 290-300rwhp range if we could of gotten everything tuned in. Dan hadn't even starting working with it yet. It looked like he just had the timing pulled back seeing where the fuel was at, so there was a lot of power left on the table. Those would of been some pretty impressive numbers on stock heads and cam.

Thomas

I never saw the cloud, was to busy watching the tach. I put the car up on ramps and will start disassembling it this weekend. I am going to see if I can barter a set of big valve ported & polished heads out of someone. I would like to get them on and finish my tune. I really want to drive my car more this year and I dont want to run 20 lbs of boost and worry about clouds of white smoke. What was really neat was when I went with Dan looking for that plug he took me in his chevy with a 2.2 whipple in it. He said he dyno it at 440 RWHP and 600 RWTQ:eek: When he stepped on it felt like being shot out of a cannon
 
Yeah - I've got video, but it's still on the camcorder. I'll be in Kansas City this weekend (I think?) and will get to it Monday or Tuesday of next week. And if anyone posts saying they want it sooner - then no video at all :D haha

I'm willing to come help too Ken :D And I know what it's like to do blow HG's.. atleast you got some dyno pulls - I didn't get even get that :D That's the nice thing about the local guys - we try to come together to help those in need. I'll post the pics up when I get home. It was a long day at work :mad:

-Melon
 
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