LT1 on the dyno today

[Geof180]

in case anyone is interested in what a stock LT1 will do, i put my 96 LT1 on the chassis dyno here at school today...

1st run - 207.9 RWHP at 4695 rpm and 237.3 ft-lbs of torque at the rollers at 4267 rpm

2nd run - 217 HP at 4832 rpm and 240 ft-lbs at 4380 rpm... both at the rear wheels...

all of these numbers are STP corrected...

this initial run marks the beginning of my auto engineering class final project ... i am gonna use these numbers, along with collected drag profile data (after i throw a 1/25 scale model Corvette into the wind tunnel here and use CFD to emperically find the Cd), suspension measurements, etc.... to do some theoretical performance calcs...

ya know, top speed, cornering, handling, etc....

now, do these numbers seem good to anyone else? a little high?? low?? or just right?? for this was the first time i had ever had my car on the dyno...

thanks..

Geof

 

[Stingray74CC]

nice

Busy little bee over there at Air Force. We're about to do our first Dyno runs on the Formula Engine. We don't have a drum, just the engine stand dynos....or maybe we do. There's alot of stuff back in that room that I haven't seen. Oh well, I can't tell you anything about your numbers but good luck with the project.

Later,

 

[Geof180]

anthony - i was just thinking... the techs might have messed something up with the test or the machine was off... shouldn't peak power be higher - i mean at a higher rpm??

oh yeah - our formula guys did their pdr the other day... well - uhh... from what i heard, the teachers were not impressed...

Geof

 

[UB2 SLOW]

These numbers are low. You should have around 240-250 at the wheels in hp. You peak power should also be around 5600 rpms. The Torque numbers are also low.

 

[UB2 SLOW]

I have an almost stock Dyno for my car at www.ub2slow.com. My numbers should be just a little higher. I turned out 255 rwhp.

 

[Edmond]

Auto or 6 speed?

Assuming that an auto will lose 20% from the engine to the rear wheels and the 6 speed will lose 15% from the motor to the rear wheels, I'd say there is something wrong with that dyno machine.

Those numbers seem just a little bit low.

With the CAC as your knowledge base, nothing short of an A on this final project will be acceptable!

 

[Geof180]

cool... thanks for the input guys....

i will go ahead and reschedule a dyno run for within the next week or so... a buddy of mine here in the squadron suggested i go up to denver and have one of those professional places do it for me as well....

as the project progresses, i will definitely keep y'all in the loop...

thank you once again..

Geof

my next step is to get the drag data.... problem - drag does not scale too well....

 

[wookiebear]

LT 1 on Mustang Dynamometer

Hi Geof,
I recently had Breathless Performance dyno my car, it is a LT-1 96 convertible, see below information.

MAX POWER 253.8 @5050 RPM Stock Run
MAX Torque 292.4 @3550 RPM

It was a very Hot and Humid day with the temp in the low 90's

NITROUS RUN (Only other real Mod)

MAX POWER 361.3 @5050 RPM Nitrous
MAX TORQUE 427.0 @ 4300 RPM

I think you should check and make sure that the dyno was tuned in to your rear differential numbers correctly, makes a very big difference. Hope this helps you out.

 

[RalleyRed]

wookiebear,

I had "Breathless" dyno my Vette at Bowling Green during SharkFest.
Nobody asked me what the rear gears were!

I'm wondering if this is why everyone was getting lower that expected numbers?

Rick

 

[wookiebear]

Breathless Performance

I had mine done at Eckler's in Titusville Florida when they had their early summer corvette roundup and Flea Market bash. I had an opportunity to talk to the Tech's that were running the whole operation and they were very helpful, they stressed that it was very important that the proper gear ratio was entered into there computer along with other little things like making sure the air conditioning unit was turned off and the traction control as well as being in 3rd gear for the final push (Thats if its Automatic). If these things are not followed to the T it will effect the final outcome of the Test.

Wookiebear

 

[RalleyRed]

Wookiebear,

I don't mind telling you that ticks me off. I'm not a cheap guy, but I expect to get what I pay for.

I know for a fact that none of us were asked what gearing we had.
I'll be contacting both Mustang & Breathless to find out what the deal is.

Thanks,

Rick

 

[Geof180]

i had to give the techs a few pieces of info before i even ran the test.....to include vehicle weight, tire diameter, bore, stroke, and final drive (3.07)....

since i have the auto, i did the test in D - not overdrive... i also had the ASR off as well...

after my next run, i will see how close i get to your first set of numbers wookie....

i appreciate the info fellas....

Geof

 

[wookiebear]

RalleyRed

If you decide to dyno the car again at any kind of public event such as Sharkfest or any NHRA major event make sure that you do it on the last day of the event when they do not have alot of people lined up to have their cars tested, This is production line work when they see that they have alot of people lined up they tend to rush the job and not be quite as thorough. I waited until they had no other cars to do and were just lounging around talking to the crowd, you probably noticed that when they test a car that a crowd tends to gather around looking to see how the numbers pump out on each machine, this gets the cvrowd pumped up for more business! Nothing like the roar of an engine to draw the spectators in! LOL! I know the 1st day of the Eckler's event they did not stop, the cars were lined up bumper to bumper to get tested and if you watch them closely, when lunch break comes the head tech leaves to take his break and one of the assistants takes over, sometimes these assistants are a little nervous with large crowds around (Kind of like the 1st time at the Christmas Tree) they are human and just forget things like we all do from time to time.

 

[RalleyRed]

Wookiebear,

I understand what your saying, but this was not the case at Bowling Green.

I doubt that there were much more than a dozen cars strapped to the dyno over the week-end, Fri-Sun

Rick

 

[Fiddler's Gold]

Those numbers

look really low IMHO. You might want to check that dyno and make sure that it was configured properly or opt for another shop. Seems like I recall that it should be in the 235-250HP range if I remember correctly from a recent stock 96 dyno that I witnessed at the Dynojet shop. Hmmm...

Hope you find something interested --- it might help you out big time.



Fiddler

 

[94c4lt1]

Gentlemen,

You are forgetting to take into effect the elevation of his location (Colorado springs, co) 6400 ft above sea level. The reduced density of air drastically reduces horsepower on NA cars.

I am not sure if 210 RWHP is low for up here or not (I haven't dynoed my car) on an LT1 vette. But what are people from high elevations getting on LT1 vettes?

 

[Vettelt193]

I thought that the STP correction fixes the elevation problem... am i wrong?