
1.9 IDI with GT1749V 15lb boost and Saab ic.
Got on the dyno today. Things to remember about the results: I have both a transfer case and an overdrive that suck extra hp down, I have bigger and wider tires than most of you which probably suck hp, I was pushing 30 amps to a fan to try to stay cool-probably a few hp there, this isn't corrected and I am at 7400' and the temp was in the 80's with low humidity. I ended up almost double the hp of my old engine, lots more torque too at above 1500 rpm. So at about 3500 where the torque starts dropping, is that from the gov cutting fuel? I did the intermediate spring mod. It gave them a fit trying to keep steady RPM's at lower RPM's as the governor wanted to increase it because of the intermediate mod I imagine, plus because the boost climbs so fast with the VNT.
Anyway, I'm happy to have almost doubled my hp while getting much better mileage. Oh, the best part is they didn't charge me this time.

Stock 2.25 gas motor
Great job...been following your build. Looks to be right around the factory numbers for a tdi...probably moves pretty good...
Is that measured at the wheels?
Double the power must wake up the vehicle nicely!
Yes, at the wheels. I love the power. Only thing I will probably change is undo the intermediate spring mod, and do the main spring mod.
Yes, at the wheels. I love the power. Only thing I will probably change is undo the intermediate spring mod, and do the main spring mod.
good thing, i dont understand why the intermediate should be shimmed?
Greetz, Benjamin
Good numbers if you have doubled the HP, still learning on these engines so I honestly don't know what "great" numbers would be anyway :lol:
Couple of things on chassis dynos I've picked up from the diesel truck world.
Altitude does make a difference, but with a turbocharged engine it's not that big of a difference. There have been many heated talks twixt the mountain boys and the flatlanders.
Figure with a manual tranny you have about 15-25% driveline loss, gearing and tires will make a big difference as well. As you noted, your large, wide tires probably hurt you, they did. My Dodge did 393HP to the rears last dyno, if I did not run a super heavy tire and rim (150lbs apiece, 34 inches tall) me and the dyno operator both feel the 400 mark would have been easily made.
Nice smooth curve, now add some more top end fueling :twisted: