Originally Posted by 93Rubie

Also my calculated 0-60 time using my 1/8th mile time and speed according to wallace racing is 4.56 seconds on a 1/4 mile track on street tires.

Originally Posted by GREGGPENN

Hey guys....Sorry I didn't assume dyno meant engine dyno (in ddalgren's comment specifically). I always assume rollers...though I DID assume the GM graph was an engine dyno comparison....especially considering the numbers! For that graph, I DID look at the scale on the right -- for HP. I'm not THAT dumb! (OK...OK...don't start a poll. LOL!!!)

Anyway...If you extend the L98 hp line to a point under the LT1 peak, you'd been looking at 315/225. That's 90hp using my math. I realize it's not "peak-to-peak", but the difference is bigger than the amount normally attached to the L98=>LT1 upgrade.

I always look at the "area under the curve" which applies BOTH to TQ and HP. When I've objected to GM's graphs it's because they are geared toward HP differences -- which aren't as easy to feel! Right? You said it! Chassis dynos are more "horizontal" in their scale. As such, I relate to what I see/feel better.

Still, I'm surprised I didn't notice that 5krpm HP difference back in the 20th century! Then again, I didn't drive them AFTER reviewing dynos and looking for those differences. I was SO young and dumb...at 40! As for the torque, I guess you made my case for going after torque in a street car!

I'm sorry...shouldn't have said THAT.....j/k.

As for my comment about approximation, I'm referring to the fact (in your link to the HotRod article) it states they built an engine similar to the 1970 Corvette. THAT was the "approximation". They didn't actually use a 1970 Corvette engine. It doesn't bother me or discount the graph (which I admitted looking at incorrectly the first time. Plus, I really DID think ddalgren referred to a roller dyno). My comment about "approximation" just means the graph could have stood alone. It means I would have appreciated a direct comparison better. (I've seen too many articles where I questioned the results....FWIW.)

The only thing I'm left wondering is why GM didn't advertise an LT1 at 315 hp versus 300? I've seen roller dynos of C3's -- which I had compared to my car already. (I also looked at the BBC dynos from back then). Anyway...I was already aware of their "deficiency" compared to newer cars. One has to think owners of newer generations look at ours the same way....which undoubtedly led to the OP's original post.

Originally Posted by 93Rubie

I like the general they cannot run 13's nonsense. I have the time slips to prove otherwise.

FYI, my LOADED with options 93 weighs about 3300lbs not sure where 3400 came from.

Also my calculated 0-60 time using my 1/8th mile time and speed according to wallace racing is 4.56 seconds on a 1/4 mile track on street tires. NOT drag radials just decent summer performance tires. So even on a slow day under 5 seconds.

Originally Posted by Tom400CFI

Say....WHAT?? I have no idea what you're saying there. Do you? Where did the "ZR1 (ZR-1?) come from in this conversation?

I'm sure that you DID see more than 300 hp on a dyno w/an LT-1....just like you would also "see more than", if you put an LT1 on a dyno with open headers, no exhaust and no accessories.

It's weird to me that this needs explaining. The graph above was apparently done using "Net HP" rating; all accessories and stock type exhaust in place. How can we determine this? Well, the '70 LT-1 was originally rated at ~370 hp...yet in the graph it made ~300. The LT1 was rated at 300 net hp and it made 3-low teens in that graph -pretty close to it's net rating.


Now let us observe another test...this one would be more like the one that you must have ran where you saw "good deal more than 300 hp. stock." That would be a GROSS hp measurement with all accessories removed, open headers, no exhaust and optimized conditions, fuel and tune. Under these conditions, you'll see that the LT-1 and the LT1 both returned just about 350 hp, in THIS TEST

Bottom line? The '70 LT-1 and the '92 LT1 both made about the same power, how ever you measure it.

Originally Posted by sprink94

...I was lucky enough to have a '70 LT-1 from a totaled '70 'vette with a 4- speed in my '56 Bel Air 2 door sedan in High School. It was pretty quick and gave all my 442/GTO/SS Chevelle guys fits !!...

Originally Posted by QCVette

For some 0-60, 1/4 mile, 20 ft, etc. a pretty cheap measurement tool is one of the accelerometer devices like a G-tech. They are usually pretty close. I have used one for a long time. They help for tuning and to practice (launches especially).

To step into the current decade though, there are some GPS applications including some for your smartphone that can do many of the same things. I think some apps like "Torque" can do some of those measurements.

Has anyone tried those GPS/smartphone applications? How well do they work?



I would have liked to try. I had a '70 W-30 455 in a '68 442, a 421 SD in a '64 GTO and a '70 LS6 Chevelle SS. I thought they ran pretty well and I ran them a lot. I was pretty stupid back then, but it was fun.