Pretty much here is my story. I have been to 2 locations for dynos. The first place I went to did a dyno run of my car. Now, I don't think they did it correctly. I believe they NEVER got an RPM signal and my dyno sheet doesn't list the RPMs nor the Torque reading. What I believe they did was dyno it by elapsed time and some how converted it to HP. My dyno sheet is literally screwed up looking...it says HP, MPH & Elapsed time. If the dyno sheet is correct my car did 125 MPH LOL which is not possible.
Now after I got my head installed, I went to go to another performance shop and they get my car on the dyno and couldn't get any type of rpm signal. They were more professional and had a different dynometer. They were getting readings of 250 HP & 400 lbs of torque...something really just way out of wack. They apologized, didn't charge me and sent me on my way.
So pretty much, I want to know who has done a proper dyno with the ECOTEC and/or 2.4 motor and how did they read an RPM signal? I know our issue is that we run off 2 coils and that's why they couldn't get a full RPM signal...so how do we fix this or how would I instruct the dyno shops to read a full RPM signal?
For informational pruposes...the first shop used DYNOJET and the 2nd used a Mustang Dyno.
If you could help, it would be appreciated....
www.kronosperformance.com / 732-742-8837
HOLY CRAP 400lb ft of torque?? You should rip your car in two with those numbers
Killa
Semper Fi SAINT. May you rest in peace.
jackalope wrote:HOLY CRAP 400lb ft of torque?? You should rip your car in two with those numbers
Killa
yeah right LOL
You have any idea on how they could get a full RPM signal?
www.kronosperformance.com / 732-742-8837
I seriously need this information also because I have been to the same places that he has been to. Hell stock I was putting 200 HP and I really want to know what my base numbers are before I touch anything. What kind of dyno is recommended, and what type of information do I need to know to figure this out. When I last went using the rollers after new calibration they where able to get a full RPM band reading but the HP and TQ numbers where still way up in the air. I would love to get a full listing including air/fuel ratio and all that fun stuff. My goal is to have my car dynoed by October so I have time but the sooner I get to schedule the better.
Defined Parts
I dynoed mine. On a dynojet.
We used the black wire with a strip or Grey (?) and hooked the rpm signal lead to that and changed it to fire every 360 degrees setting.
So rpm lead to black wire strip and change computer imput, so that the computer knows the spark fires every 360 degrees of crank rotation
My Car
200 hp stock? I think you had the same dyno that Killa did to get his 400lb ft of torque.
I wish I knew Killa but the last time I dynoed a car was back in like 95 I think and it was my Firebird so I have no clue as to what to do on our cars. Remember I was asking you about my header and cams. I still would like to know a few things but I won't jack your thread. Just respond in mine please.
Semper Fi SAINT. May you rest in peace.
i was told its the pink wire from the ICM and then set the dyno to read a 2 cylinder
id really like to know for sure as well
The one, the only, ME.
To tell ya the truth any shop should be able to do this. This was my first time (on this car) dyno'ing. We tried different leads, found one that worked (so the screen said it was idling at 900rpms) after we set it to spark every 360 degrees. The car has two coils so the coil will fire both sides of the coil at the same time. One cylinder on compression the other on exhaust.
The very top black wire we used for rpm pick up
My Car
Okay, so I dynoed the black car today
. You can use the pink or black wire I already stated.
And you have to set up the computer to spark every 180 degrees.
So 180 degrees, NOT 360 like I said before.
My Car
go NJ ! I'm really looking forward to seeing some numbers from your beast.
15.891 @ 88 mph stock, still getting @!#$ty launches...
DanteMustDie wrote:go NJ ! I'm really looking forward to seeing some numbers from your beast.
I'm going to do this more than likely after I'm boosted...if I'm lucky before cause money is tight like a virgin.
www.kronosperformance.com / 732-742-8837
from what i was told was just put the rpm pick up over all the wires at the ign module , works on both the eco and the 2.4
GM DIS has been around for enough years that the dyno guys should know to select 180 degree plug firing. If you have plug wires and a stock ignition, the best results usually come from using the secondary pickup on the plug wire. But a primary pickup connected to one of the 2 coil trigger wires would also work, especially when there are no easy to reach plug wires.
Is the engine you're dyno testing bolted to an automatic trans? Believe it or not, auto transmissions can produce bunches of torque through multiplication built into the torque convertor. I worked in a dyno and performance shop, ran a dyno for over a year in fact. Torque readings obtained at low wheel rpm, high engine rpm, and with the trans in 1st or 2nd gear especially, will be too high. Technically they will be correct for the amount of torque produced at the wheels, but they will not be close to correct for the amount of torque produced at the flywheel.
The mass of the drum in the Dynojet dyno is known. The speed of the drum is measured by a sensor on the drum's axle. That's all that is needed to get an accurate horsepower reading. The acceleration is calculated from the changes in speed, and the horsepower required to create that acceleration is calculated. And since the rpm of the drum is known, torque can be calculated from hp. You could take tq and hp readings by chaining a bicycle to the drums if the speed sensor had the resolution.
The RPM reading is only to give you a reference for the graph. MPH is another viable option, although less so for auto trans engines. Since the size of the drum is known (drum temperature is actually monitored... presumably the Dynojet software will lookup the change in size of the drum as temperature increases) the speed in mph of the tire travelling on the drum can be determined from the measured drum rpm. When tire circumference, final drive ratio, and the trans gear ratio are known, engine rpm can be calculated. Auto trans engines have this problem called "converter slippage" which will change actual engine rpm by about 2% under light load to ?% (depends on converter) under full throttle. I never used MPH because I always thought is looked stupid to give the customer a graph of hp vs speed.
Why is it not possible for your car to do 125 mph??? If the tires are larger than stock, it certainly is possible. All it takes is a 14% difference in tire size to allow a car with a 108 mph speed limiter to reach 125mph before the limiter kicks in. With no wind resistance against the car, the engine will push the wheels to a far greater speed than they'd see on the highway. But the guys running the Dynojet should have entered the correct speed rating for the tires. Then the dyno would have aborted the run if tire speed exceeded the recommended limit.
FWIW, they (the Dynojet guys) may have saved your dyno run. We always did. If you can get a copy of it you can use free software from Dynojet to view it. If the RPM reading is available then you can view a graph with RPM instead of MPH.
On a Dynojet you can also get a good idea of the mass of your drivetrain by doing a coastdown at the end of the dyno run. When you get to the end of the power run, push in the clutch of shift the trans to neutral (for autos). The dyno will measure the inertia of the drivetrain and display it as negative horsepower. You can use this to get a better estimate of engine hp at the flywheel. Just don't hit the car brake pedal!!!!
I can recommend a few shops in eastern MA and NH if all else fails.
HTH
-->Slow
On my 2.4's we have had them put the clip around all the wires goign into the IDI, got RPM signal fine. Heard the same works for the Ecotec, but seems someone else has better ifno above.
