this is where the over-all efficiency of the system will stand out, whether good or bad, be nice to know EGT as well....opcorn: from some of the searching we have done in the past, the M-112 is still a bit on the small size for our air requirements, better yet would be to try out what dieselpro mentioned earlier about the electric clutch to pop it out of the system at higher rpms.... we have an M-122 on the shelf, but the biggest issue i see with it is the shorter snout making it harder to place for belt alignment....Are you planning to install air temperature gauge to see how hot it is after the charger?
So how I see it, the only senseful solution here is to buy another M112 and twin supercharge.The jag snout isn't as common over here.
You can buy a jag snout kit but you will pay almost as much for the jag snout as the cost of a used take off M122 from a pony car.
Running 4psi at idle now might be a good time for that bypass unless you want it to warm up faster during idle.
i think the m-112 would be perfect if you ran an electric clutch, and used the m-112 to spool up a large turbo, that was also exhaust driven, like a HT3B holset with a 26-28cm2 exhaust turbine, or an S475 borg warner, you would have an intense set-up that would probably pop your stock engine.... but would be the best of both worlds, and seriously haul ass....Yes, i have to do the intake temp gauge some day soon. Too bad i didn't realize the need when the first 6.7" pulley. That would be good reference data to compare the pulley ratio efficiency. Now the adapter is modified to ATI pulley, and i can't easily go back to read the 6.7 pulley again.
With the 6.7" pulley (2.4 ratio) the engine was acting good. not much difference to normally aspirated, but noticeably better usable power. Good behaving and silent engine.
With 9.2" pulley and 3.3 ratio, engine feels like a poorly tuned race diesel
Looking at the oilpan4's fifty shades of blue for m112 power requirement, i can see Eaton is pulling 50-60hp parasitic to generate 14psi above [email protected] ([email protected]). At cruising, 2krpm, crank power loss is ~25hp (8-9psi @ 6600 SC-rpm).
No wonder the feel of pants performance did not increase too much comparing to the first pulley edition. Nevertheless, I think i just had to experiment the boost limits. This is a learning process. I am trying to find the best of both worlds - power and efficiency.
Now running the big ratio pulley with bypass open it feels right. Nice torque all around, as a mild big block down low. The by-pass, as mentioned previously, is a heater core valve. The orifice diameter is about 16mm (5/8"). By-pass-valve open, the pressure is approx 2psi @idle, 5-7psi cruising and 9-10psi max. I suppose this is the correct pressure level to shoot for, with stock IP and M112. The M112 might get too far off out of zone on higher boost levels. As @turbonator says, maybe an M122 would do better for high boost.
I don't think it is efficient to run big pulley and bypass the once pressurized and heated air back to the SC inlet. So i still need a new pulley.
Doing the math, a crank pulley 7.5-8" (~2.7 - 2.9 pulley ratio) should do the aimed psi.
The 9.2" pulley will be stocked on my shelf for the day when i have a new/modified IP for better injection potential, and have maybe an intercooler installed.
I'll do the requested video someday
Well now, if that aint somethin!i think the m-112 would be perfect if you ran an electric clutch, and used the m-112 to spool up a large turbo, that was also exhaust driven, like a HT3B holset with a 26-28cm2 exhaust turbine, or an S475 borg warner, you would have an intense set-up that would probably pop your stock engine.... but would be the best of both worlds, and seriously haul ass....
crazy carl has tried many different versions of this on the cummins, from single turbo to triples spooled by super chargers.......
first attempt https://youtu.be/ER9ddBIseTo