1970 LT1 torque/horsepower curves
 

does anyone have, or know where i can find, dyno graphs of the torque/horsepower curves for a stock 1970 LT1?
Bill

Have you asked in the C3 section?

If that does not pan out or there are not any good replies here I would suggest going to http://www.speedtalk.com/forum/.

Doug

Bill:

These are published in Best of Corvette News, p. 579

Bill

Bill
thank you very much, i would have never thought to look in there (haven't looked at that book in years.... :willy: )

http://i42.tinypic.com/23v1xj.jpg

Bill

Those graphs are bogus. HP and TQ have to cross at 5250 rpm. :ack:

:iagree:

Good eye :thumbs:

As soon as I realized that I could not read the print without a magnifying glass I gave up....... but for sure if they do not cross at 5250 they do not reflect a real dyno run on a real motor....... more like a sales department clerk's handiwork

Doug

Take a closer look at the scales. The torque (ft-lb) and power (hp) only cross when they are both plotted on the same scale. 5252 is only a conversion factor; 1 hp = 5252 ft-lb * 1 rpm = 1 ft-lb * 5252 rpm. There is nothing magic about crossing at that number and being a "real" plot. It only means power and torque are plotted using the same scales. They weren't for these plots.

Cheers,
- Brad

Zigler is absolutely correct.

Look at the torque on the right hand scale at what you interpolate to be 5250..... it's something less than 360 ft-lbs.

Now look at horsepower on the left hand scale at the same interpolated 5250 RPM and you get something less than 360 HP.

There's your mandatory "crossover".

Jim

Biiger graph
 

i was trying to keep people from having to pan sideways.
yes, there are different scales on the right & left sides.

http://i42.tinypic.com/2ngv77t.jpg

the reason i asked was that with a 3.36 rearend and a .73 OD,
the normal rpm range that my LT1 operates in is 1500 to 2500
and i was trying to determine what the most efficient operating
'sweet spot' was for that engine

Bill

With the larger print I can see what you and Zigler are saying

Ok...... my bad :o

Doug

I like the fact that the LT-1 HP is still climbing at 6000RPM where the LS-5 is laying down at 5100RPM. You should remeber the early SAE testing was done with a 30/30 cam and not the LT-1 solid cam, many think the LT-1 gives away 10-15HP from the SAE test. My 70 LT-1 needs to get to 2200-2400RPM before she is really happily running (possibly because of running pump gas+additive when running on 30% race gas/pump gas mix she is much happier.)

yep, that's about what i figure, i find myself trying to keep above 2000
by driving in 2nd or 3rd around town and not using OD until i get above
55 (which just almost gets to 2000. 75 is just about 2250). the Rochester
FI handled it well on leaded gas in the summer. but for as much as i drive it
would be too expensive to use racing fuel, even as a mixture (and i would
have to drive 20 miles just to get some...)...
Bill