Has anyone tuned with a motec?

[sleepyEK]

I'm using a motec m4 to tune a genesis 80fi with head shim and garrett gt12 turbo. I was curious if anyone has any suggestion as far as base ignition and fuel maps. I'm using two 370cc injectors. i've managed to actually get the engine started and running for a bit. Any info would be greatly appreciated as there is hardly any information on this engine.

 

[Need for Speed 2]

sorry I vant help but I would love to see some pics, I am thinking of doing a turbo phazer

 

[sleepyEK]

it's actually not on the snowmobile, it's on a test bench that i made so i can use the land & sea engine dyno. but if you are interested i could send you some pics.

 

[Ted Jannetty]

I'm using a motec m4 to tune a genesis 80fi with head shim and garrett gt12 turbo. I was curious if anyone has any suggestion as far as base ignition and fuel maps. I'm using two 370cc injectors. i've managed to actually get the engine started and running for a bit. Any info would be greatly appreciated as there is hardly any information on this engine.

Are you using to additional 370 cc injectors?
By my calculations you only have enough injector for about 72 hp at 42.5 psi fuel pressure, the system may run at 60 psi covering the 80 hp it came with but with the turbo I expect you will need more like 2 750 cc injectors.

Because of the high RPM the 80fi turns I expect the turbo will be too small also, the GT1548 would have been a better fit, but I don't know what your trying to do.

 

[sleepyEK]

thanks for the reply. i should also mention that i have to use a 20mm intake restrictor, which limits the actual horsepower that can be made. not trying to argue, but i'd hate to think that my in depth engineering analysis would be inaccurate. i have calculated that with the maximum mass air flow, i'll be just under choked flow through the orifice of the restrictor, which means that if i could even achieve a higher mass air flow rate from the engine, i wouldn't even be able to make any more power. by my calculations i actually only need two 350cc injectors, but decided to go higher due to limitations on availability.

also by my calculations and analysis, the gt12 turbo is very ideal for the corrected mass air flow and the pressure ratios we'll be seeing. according to the numbers that i get, we'll be right in the middle efficiency island with no danger of overspeeding or compressor surge. regardless of my calculations, i have built a very detailed model of the engine in ricardo wave, which is a very trustworthy wave analysis code used by many engine designers. the model interprets the compressor and turbine maps for the gt12 turbo sent to us by garrett. it also uses a highly discretized cad geometry of the restrictor. it's showing very desirable torque down low, and just over 100 horsepower from 10k to 12k at 29.7psia (15psig). these are very good numbers for a fsae setup, which by the way requires the throttle plate to be upstream of the restrictor and the turbo.

 

[Ted Jannetty]

thanks for the reply. i should also mention that i have to use a 20mm intake restrictor, which limits the actual horsepower that can be made. not trying to argue, but i'd hate to think that my in depth engineering analysis would be inaccurate. i have calculated that with the maximum mass air flow, i'll be just under choked flow through the orifice of the restrictor, which means that if i could even achieve a higher mass air flow rate from the engine, i wouldn't even be able to make any more power. by my calculations i actually only need two 350cc injectors, but decided to go higher due to limitations on availability.

also by my calculations and analysis, the gt12 turbo is very ideal for the corrected mass air flow and the pressure ratios we'll be seeing. according to the numbers that i get, we'll be right in the middle efficiency island with no danger of overspeeding or compressor surge. regardless of my calculations, i have built a very detailed model of the engine in ricardo wave, which is a very trustworthy wave analysis code used by many engine designers. the model interprets the compressor and turbine maps for the gt12 turbo sent to us by garrett. it also uses a highly discretized cad geometry of the restrictor. it's showing very desirable torque down low, and just over 100 horsepower from 10k to 12k at 29.7psia (15psig). these are very good numbers for a fsae setup, which by the way requires the throttle plate to be upstream of the restrictor and the turbo.

I figured you were doing something Abstract, I saw your signature, but just thought I would throw it out there.

Sounds like a Cool Project would love to see some Pictures and a little more Detail on it.

Ted.

 

[dynotechjim]

some years ago I loaned my dyno facility to engineering students at UB(Buffalo NY) for a similar project, using a honda 600 4cylinder with a turbo and that awful 20mm restrictor. As I recall, that engine peaked at about 100hp at very low revs with the 20mm restrictor. Air velocity through the 20mm restrictor maxed out at that peak HP RPM at the speed of sound and airflow CFM flatlined beyond whatever RPM that occurred at. Then as revs climbed, hp dropped a bit as friction ate up more HP as the square of engine speed. I learned interesting stuff from those smart kids.

 

[sleepyEK]

thanks for the replies guys. yeah it's really quite interesting trying to squeeze as much as you can out of an engine using a restrictor. the honda motor definitely maxes out the airflow. interesting though, according to my analysis, the yamaha engine won't achieve choked flow at the orifice. this is good, as the turbo would likely overspeed trying to maintain the desired boost choked flow conditions. there would be some really high pressure ratios as the inlet pressure would drop very low. i'm still curious about ignition characteristics for this engine though. if anyone has any input about some rough ignition values, please let me know. thanks.

 

[dynotechjim]

when the UB kids' honda 600 4 cyl achieved "choked" airflow, I'm assuming that's air velocity = speed of sound (some particular SCFM) through the 20mm restrictor, why wouldnt the yamaha do the same?
assuming BSAC is similar for both engines, wouldnt your turbo be able to yank hard enough on that inlet restrictor to create the same 100hp worth of air at very low revs? That's surely the advantage of the turbo in your class of competition--make that 100 hp at as low an RPM as possible and have that flatline to high RPM giving you the best average HP through the powerband using a gear transmission.