JDM Diesels

dvldoc · 05-16-2008

Heres a Isuzu Dyno from yesterday. I believe DO2 nozzle but I'm not sure and I don't know what mix they used.

Darbym · 05-16-2008

Nice gains throughout rpm band. Didn't seem to get that big boost of low end torque like some of the other diesels, could that be do to nozzle placement, or possibly the size of the factory turbo on the motor compared to some of the other vehicles? HP also didn't seem to drop off at higher rpm's.

dvldoc · 05-16-2008

These engines are built so different from the different car makers every dyno is normally a bit different. I also have no ideal of how much alcohol they used. I told them to start out with just 30% and play with it from there. So that is probably only 30% alcohol on both runs.

One thing different about this one is they started at 2000rpm vs the 1500rpms, I think if you saw it from there you would see a bigger difference in TQ. The guy says he loves how the truck drives now. I thought the 2.8 would make more power than that stock but there pretty weak on power. But it is a older vehicle.

Darbym · 05-16-2008

I actually expected alot more. From the factory rated horsepower and torque there would seem to be an approx. 50% in driveline loss from the dyno results. Only peaking at just over 108 ft.pd of torque seems extreemly low for factory rated power. The gains are still very impressive on the overall results, jus a lot lower than I would have thought.

Dust · 05-16-2008

Is everything about the vehicle up to snuff? Sounds like there are some other issues.

dvldoc · 05-18-2008

Quote:

Originally Posted by Darbym

I actually expected alot more. From the factory rated horsepower and torque there would seem to be an approx. 50% in driveline loss from the dyno results. Only peaking at just over 108 ft.pd of torque seems extreemly low for factory rated power. The gains are still very impressive on the overall results, jus a lot lower than I would have thought.

That engine is only rated at this stock. I notice some publications have it rated higher. It does not have the same specs as a trooper though they share the same engine model name.

Quote:

:KW(PS)/rpm, 58(79-HP)/3900. Max.Torque:Nm(Kg.)/rpm, 176(18.0)/2000 (129lbs TQ

So with 17% drivetrain loose which is the average it should be making 63HP AND 107LBS tq in peak operating conditions.

The dyno showed 64hp and 108lbs tq so i would say that's pretty nuts on accurate.

Terry Syd · 05-18-2008

The peak of the 'before' torque curve is the depression of the 'after' torque curves (2500 rpm). This indicates to me that the injection timing was probably spot-on for straight diesel and the addition of the methanol in the WI advanced the burn rate so that what was a peak before, became a depression after.

Likewise, after peak torque (peak volumetric efficiency) the addition of the methanol had a more positive effect on the rate of pressure rise in the cylinder.

If the injection timing was retarded just a tad I would expect the 'after' runs on WI to look more like the curve of the 'before' run.

05-16-2008	#11 (permalink)
dvldoc DevilsOwn Staff Join Date: Apr 2005 Posts: 2,074	Re: JDM Diesels Heres a Isuzu Dyno from yesterday. I believe DO2 nozzle but I'm not sure and I don't know what mix they used. __________________ Currently deployed to Ramadi 1 battalion 12th Marines Task Force MP

05-16-2008	#12 (permalink)
Darbym Water Injection Newb Year: 1992 Make: Toyta, Isuzu, Nissan Model: Landcruiser, Bighorn, Figaro Join Date: Mar 2008 Posts: 10	Re: JDM Diesels Nice gains throughout rpm band. Didn't seem to get that big boost of low end torque like some of the other diesels, could that be do to nozzle placement, or possibly the size of the factory turbo on the motor compared to some of the other vehicles? HP also didn't seem to drop off at higher rpm's.

05-16-2008	#13 (permalink)
dvldoc DevilsOwn Staff Join Date: Apr 2005 Posts: 2,074	Re: JDM Diesels These engines are built so different from the different car makers every dyno is normally a bit different. I also have no ideal of how much alcohol they used. I told them to start out with just 30% and play with it from there. So that is probably only 30% alcohol on both runs. One thing different about this one is they started at 2000rpm vs the 1500rpms, I think if you saw it from there you would see a bigger difference in TQ. The guy says he loves how the truck drives now. I thought the 2.8 would make more power than that stock but there pretty weak on power. But it is a older vehicle. __________________ Currently deployed to Ramadi 1 battalion 12th Marines Task Force MP

05-16-2008	#14 (permalink)
Darbym Water Injection Newb Year: 1992 Make: Toyta, Isuzu, Nissan Model: Landcruiser, Bighorn, Figaro Join Date: Mar 2008 Posts: 10	Re: JDM Diesels I actually expected alot more. From the factory rated horsepower and torque there would seem to be an approx. 50% in driveline loss from the dyno results. Only peaking at just over 108 ft.pd of torque seems extreemly low for factory rated power. The gains are still very impressive on the overall results, jus a lot lower than I would have thought.

05-16-2008	#15 (permalink)
Dust Alcohol Holic Year: 1999 Make: Daihatsu Model: Move Join Date: Mar 2007 Posts: 337	Re: JDM Diesels Is everything about the vehicle up to snuff? Sounds like there are some other issues.

05-18-2008	#17 (permalink)
Terry Syd Alcohol Holic Year: 1990 Make: Toyota Model: Hilux Join Date: Nov 2007 Posts: 104	Re: JDM Diesels The peak of the 'before' torque curve is the depression of the 'after' torque curves (2500 rpm). This indicates to me that the injection timing was probably spot-on for straight diesel and the addition of the methanol in the WI advanced the burn rate so that what was a peak before, became a depression after. Likewise, after peak torque (peak volumetric efficiency) the addition of the methanol had a more positive effect on the rate of pressure rise in the cylinder. If the injection timing was retarded just a tad I would expect the 'after' runs on WI to look more like the curve of the 'before' run.