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Daves
03-14-2005, 11:56 PM
I recall reading or hearing somewhere about an enormous amount of torque that Georgia Tech achieved with their Honda FSAE engine. Am I making this up, or is it really true? What are their previous peak horsepower and torque values?

BeaverGuy
03-15-2005, 02:17 PM
They posted their torque and power curve in a thread titled small turbochargers. The curve is amazing for a naturally aspirated motor.

Fred the Gypsy
03-15-2005, 04:02 PM
Here it is again, I am quite proud of it:
http://www.77spider.com/images/gtmotorsportspower.jpg

All it takes is good testing and getting the basics very right. The staged injection helps make it smoother but it's not too important to make good power from 4500-14000 rpm, thats what gears are for. The engine comes with a six speed, might as well use at least half of them.

Daves
03-15-2005, 05:17 PM
Thanks for sharing the curve, Fred the Gypsy.
However, the GT Motorsports website claims "86 horsepower and 52 ft-lbs. of torque" (http://www.me.gatech.edu/gtmotorsports/text/gtmsprogram.html) Was this on a different year car? How do you get so much torque out of the F-series Honda engines?

Garlic
03-15-2005, 06:05 PM
Don't beleive what you read on websites. http://fsae.com/groupee_common/emoticons/icon_wink.gif Someone probably decided to correct it for transmission losses or something. (And was generous when doing so)

Daves
03-15-2005, 08:05 PM
Don't beleive what you read on websites.

Garlic,

If what you say is true, I do not believe you.

Matt N
03-15-2005, 08:46 PM
That makes my brain hurt. Thats a nice little paradox there http://fsae.com/groupee_common/emoticons/icon_confused.gif

Matt

RickyRacer
03-15-2005, 09:51 PM
Did you dyno the engine at the crankshaft by modifying the side casing or did you run it off of the output shaft of the transmition? Any onther teams please feel free to chime in also.
Ricky
Long Beach State Racing

Daves
03-15-2005, 10:02 PM
We at LeTourneau connect a CBR600 F4i rear wheel and tire to the F4i 16 tooth 525 sprocket on the transmission using a chain. Then the tire is placed on a standard Dynojet motorcycle dyno. We made a stand to hold the engine about where a motorcycle frame would.

I have read that Dynojet dynamometers may correct for the transmission losses, but can anyone verify this? Is the power curve we see really power at the engine, or is it power after transmission, chain, and wheel losses?

fsae racer
03-16-2005, 01:47 AM
As far as I know, a dynojet like the one that you are using, dave, will give the torque/hp measured at the drum. On those lines, dones anyone know about how much hp is lost from the counter shaft sprocket to the tires on the conventional torsen rear ended sae car?

RickyRacer
03-16-2005, 11:52 AM
For all of you whith dynojet chassis dynos, does your dyno have a load control unit or do you just use the load created by the inertia or the rotating drum. I would assume that you would only loose about 5% fo power becuase I have been told by many that in a standard car with a manual transmition, you loose about 12%, so if you factor out the trans, I would assume 5%, but then again you know what happens when you assume.
Ricky
Cal State Long Beach