Do these rear wheel horsepower numbers match the engine horsepower numbers?

245 rwhp=300hp at the engine?
255 rwhp = 310hp at the engine?
Thanks..........

 

245rwhp with a 25% drive loss for an auto, is 306 flywheel.

 

i think loss would be more like 20% and 245 rwhp is like 306 flywheel

 

Yep, 306 and 318 at the engine with a 20% drivetrain loss.

 

autos can see a 25% loss, sticks around 20%.
1989GTATransAm - look at your own estimates in your sig.
304 x 1.25 (25%) = 380.

 

380 times .8(80%) equals 304. Or 304 divided by .8 equals 380. Or 304/380 equals .8 or 80%.

 

List your engine setup to reach 245 at the wheels.

 

Here are the mods,I have the dyno sheets too if anyone wants to see them.


FlowMaster Cat-Back w/high flow cats from Cat-co
EdelBrock TES Headers
EdelBrock High Flow TPI Intake Manifold
EdelBrock High Flow Intake Runners
EdelBrock Air Foil In Throttle Body
Throttle Body Bypass
TPI Intake Manifold and Runners Ported by TPIS
TPI Plenum Ported
TPIS Adjustable Fuel Pressure Regulator
TPIS- ECM Reprogrammable Chip
Gutten Air Box
K&N High Flow Air Filter
ACSD 82-92 Camaro IROC TurboHood
HyperTech Chip Stage One
HyperTech 160 Degree Thermostat
Re-mapped Injectors
MSN Ignition, Blaster Coil
Accel High Performance Rotor,Wires
Beefed up Alternator
Mass Air Flow Sensor [cut out fins]
ARP Engine Fastener Kit
Synthetic Motor Oil
3.42 Rear End
245/50/16 Radials

 

i think i've seen a dozen threads already of this guy posting the list of mods that were done to his car by the guy who sold him his car. he's always asking about what his power numbers are or should be or could be and 0-60 times or whatever.
give it up man, who cares what your flywheel hp is.
you got a dyno sheet and you ran at the track, those #'s are all that matter.

 

Ya I know lol. Just curious...Someone asked me to list my engine setup so I did

 

So you guys say there is a 20-25 percent loss. Is there the same percent loss when talking about the torque at the rear wheels as well?

 

Well if you are just curious then you already have your answer. Conventional wisdom 'estimates' drivetrain loss at 15% for manual cars and 20% for auto transmission cars. There are MANY factors that drive the actual loss (transmission, convertor if applicable, rear end) which is why it is an 'estimate'. IMO, I think that most get pretty liberal when determining what their drivetrain loss is (for example numbers start going north of 25% in order to prove a number that is in someones head). If you just want a big number to brag about assume a drivetrain loss of 65% and have a good time.

Your trap speed on a corrected timeslip is probably the best real world number to use to determine hp.

I would be very interested in seeing any dyno data that folks here may have from and engine dyno and then a chassis dyno with the same engine, same tune, etc.

-Schultzy

 

Ya I was curious what the percent loss was. I thought it was somewhere in the 15-25 percent area,just wanted to confirm it with the experts in here....If your intrested in the dyno sheets I will post them when I get some free time this week...

 

I ahve roughly the same setup but with a ZZ4 cam and SLP 1 3/4 headers I got 255 rwhp and 318 rwtq untunned

 

My rwhp 245, rear wheel torque is 325, ill try to get the sheets up by thursday or so...What do you think of the ZZ4 cam?

 

You guys are figuring 25% loss for an auto? We always figured about 16% for an auto and 12% for a manual...why 25?

 

So is it a TPI manifold and runners or Edlebrock ? I am confused.

The ZZ4 cam works great for me . But I can really feal it die off up top ( 5000 ) but I am only lossing 20 hp from 4900 to 5600 rpm. But I could feal it for sure. I put in a set of 3.73's with it ...and around town its a real blast to drive ( 5 speed) . Good strong mid range.

 

edelbrock TPI stuff ported by TPIS

the TPIS bigmouth base is pretty much just what he did, a edelbrock casting ported out and TPIS name on it

 

Yup.....

 

Here are my rear wheel numbers....

 

Run 3-TPIS
Run 15- HT
Run 14-TPIS
Run 4-HT

Ran it twice with a Hypertech stage one,and twice with a TPIS reprogramable. The hypertech looks to make better power...

 

Best HP 242.44 w/HT
Best Torque 323.99 w/HT

 

what were you revving too? 4500?

 

4750

 

damn...I was wondering...usually horsepower and torque are equal at 5250 and I didn't see that, so I knew it was fairly low. 4750 isn't very high at all

 

Next time I get it dynoed should I rev it higher?

 

Its up to you, I'd run it to redline at least. It'll amaze you how it falls off after 5000.

 

I also have some timeslips as well. I got some from when the car was stock. If anyone is interested let me know.

Stock-14.8@94
All mods above with 2.77 gears. 13.8@97
3.42's 13.5@99

 

Not bad. The best that I've had so far is 253rwhp and 355 rwtq.. Neat thing about that is that I have a totally stock intake, heads, short block... The best time that I've gotten out if it is 13.7@103.16mph with a ****ty 60' and a fubar trans.

 

Thats really good...I was thinking once I get more experience at the track my times should improve. The times with the 2.77's look about right. The 3.42 times should be lower...