Torque vs Power??

Jan 22nd, 2003, 02:10 AM

I have a R32 GTS25T modded with all the under hood go fast goodies except a cooler, and the drive line is crap, (However just found a sec hnd 25T driveline)
The problem is I am producing a massive 650 Nm of Torque and a pathetic 177Kw of power at the rear wheels. I have had three seperate dyno runs that all conclude basically the same results.

Can anyone help me solve the puzzling result?

The car is a hybrid of components including a naturally aspirated head and cams, could this be the answer to the problem?
Or is the problem the fact I am running an automatic rear diff (from original car setup) being so lowly geared, that the power can't be delivered properly to the rear wheels?

Thanks for any help.

Nismo Skyline · Jan 23rd, 2003, 10:48 PM

If you could give us a specific list of what you have, maybe someone will be able to give a few suggestions. What type of cam, which head, turbo, block, pistons etc.

fastpakr · Jan 24th, 2003, 08:51 AM

That sounds like some kind of fuel falloff. To get torque / hp numbers like that, you're nearly approximating the power curve of a diesel. Your torque peak can't be any higher than 2600rpm, and I'm guessing it's significantly lower than that unless it's dropping off almost instantly afterwards.

skylineawd · Jan 24th, 2003, 12:28 PM

What RPM are both of those numbers reading off at?

fastpakr · Jan 24th, 2003, 12:31 PM

Without him posting that, you can at the least infer that the torque figure is no higher than 2600rpm (above that, and the horsepower figure would have to change). It also has to be falling off abnormally rapidly for the same reason.

skylineawd · Jan 24th, 2003, 12:35 PM

yeah, it has to be something with the fuel, it just doesn't make sence to me why though????

fastpakr · Jan 24th, 2003, 12:36 PM

I'm not sure either. I'd love to see a breakout of the O2 signal during the run to see how lean it went.

skylineawd · Jan 24th, 2003, 12:41 PM

hehe yeah, although the part about the transmition would be the only other part that would make sense.

fastpakr · Jan 24th, 2003, 12:44 PM

I'm not following you on that one - if it can read that kind of torque number, the RPM it's generated at shouldn't really be affected by the transmission. To clarify something - I know next to nothing about the control system on Nissans (especially Skylines). Is there a speed (not rev) limiter involved here that might be kicking in, keeping them from doing a full dyno pull if they're trying this in top gear?

skylineawd · Jan 24th, 2003, 12:48 PM

well if he said it's an automatic, it should have 4 gears, and they do dyno pulls in third so that sort of thing shouldn't happen. Unless they do something different at this place, but I have always seen dyno pulls done in third. I will see if I can find anything out on that transmition.

Jan 25th, 2003, 10:44 PM

At this point in time I am not quite sure what sort of cams are in the head, but from what I can gather from the cars past they could be NA cams. I have not quite had the time or money(due to blowing up gear boxes, my computer failing etc) to open her up and have a good look inside. I am running a T04 garret with stock exhaust housing machined to take the T04 impeler wheel. I have EVO injectors, V8 fuel pump, exhaust, air filter, Brass button clutch, GReedy Profect B boost controller & Link plug in computer. Yesterday was my first drive with the new 25T gear box, its been off the road for a couple of months waiting on this gearbox...it feels great! Will save up more money to find out exactly what type of pistons, cams etc are in block. Thanks for all feedback! Builder Jim.

skylineawd · Jan 27th, 2003, 05:45 PM

No problem man, good luck with the car, and keep us informed about what all goes on with it, and any new info into this mystery.