RestoMod
This weekend I took my car and had it dyno my results were 365 hp and 354 tq. My entire build 6.1 Hemi/ 727 torqueflight/ B & M shift kit/ ported and polished intake/ ported and polished heads/ TTI long tube headers/ 180 therostat/SLP underdrive pulley/3:55 Gears sure grip/power steering delete pulley/ B & M 2400-2800 stall converter non lock up, 90 mm Throttle Body , cold air intake, catch can, Cam specs Intake Duration 267 Lift .583 Exhaust Duration 270 Lift .566. After the guy finished tuning and dynoing he car he told me not to get wrap up with the number the car is more than likely making 420hp and to keep in mind i don't have a lock up converter. My question is what does a lock up converter do that a non lock up converter will not? I based a lot of my build off of what other people who have done with LX cars and small upgrades here and their and they always come up with at least 420 in hp and sometime that in tq some a lot better I'm trying to figure out were I went wrong is it components I didn't put some vendors names on here so I don't cause doubt in their product but I just want more power and a lot more then what I got. Worst case i was suppose to make 415hp to 430. The best was 425 to 440. The engine along makes 425 hp and 425 tq and with all the aftermarket parts I still didn't get that. The dyno was a dynojet if that help any. Could I loses that much power in the drive train.

I own an engine dyno not a chassis dyno,but I studied A LOT about dynos and the ins/outs and how they work before I bought anything.
Chassis dynos are excellent for tuning a car,making comparisons on the same car with different parts.
But you have to use the same dyno and hopefully the same operator each time to compare.
You can change to a light weight wheel and see a hp gain on a chassis dyno.The engine does not make more power,it does accelerate different with light wheels.
How hard the tires deflect by cinching down the straps will even affect it.
Don't get hung up on the engine hp number,it can only be guessed at on a chassis dyno.
Keith

He is right! Don't get wrapped up in the #s. Some dynos are very stingy. I put my street smallblock duster on the dyno one time. Back then I had it running really low 11s. So much to my surprise when I could only muster 355hp at the wheels.

Get it to a track and see how it does there!

The lock up conv wont have any slippage so it would
show a higher reading... you could add about 7% more
for the slippage in the conv(7% is just a round figure)

The chassis dyno will give the actual raw power at the wheels for the current altitude, temperature, and humidity. It is then usually converted to a standardized SAE corrected number which is usually a higher number than the actual measured numbers.
The dynojet also calculates a "gear ratio" based on the drum speed and engine RPM, but it can vary based on converter slippage and tire deflection. Changes in that calculation usually have larger effects on torque than HP.

As Keith said, don't get hung up on numbers. A chassis dyno will show you if your changes are going in the right direction. It can be a very useful tuning tool. Dave

Different style converter, transmission, drive shaft, rear end....all the things that gobble up hp. On the LX cars, it's 65-70 worth, on your car it may be 100 hp. Is this true that my car could gobble up a 100 hp? It's a 66 Plymouth Belvedere with a B&M stall converter 2400-2800 rate, 8 3/4 rear end with 3:55 gears, Eaton Detroit Truetrac Differential sure grip, Transmission is a 727 Torque Flight, wheels 14 inch stock.

You can only compare an lx car if it was on that same dyno. And if you are referring to magazine articles you can bet they used a very happy dyno. I've yet to see a magazine article where they used a stingy dyno. And yes every chassis dyno is different especially different brands. Like everyone says get it to the track. You may then be very surprised.

The engine along makes 425 hp and 425 tq and with all the aftermarket parts I still didn't get that. The dyno was a dynojet if that help any. Could I loses that much power in the drive train.

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I assume you had the engine dynoed (on a engine dyno)
and if it made 425 HP and TQ then the chassis dyno
numbers arent really that far off when you figure in
drive line and slippage..... plus was the engine HP/TQ
numbers corrected or not.... plus thats the HP on
that given day(hp will vary from day to day based
on temp and other factors)