Dyno Disaster

[RDF]

I took my car to the shop today to get Dyno'd and left feeling ugly.  My 'Cuda has a 74 360 in it that was rebuilt about 4 years ago (not by me), so I wanted to see what it would do as far as HP goes.  I was thinking in the neighborhood of 280-300ish, boy was I wrong.   Are you ready for this?  A mind numbing 230hp and 270ft. lbs of torque at 5000rpm, that's it!               How could it pull such a small amount of hp?   

Just gives me reason to start my 440 build-up sooner that expected. 

[VTMopar]

Hmmmm     That is very dissapointing.   I have a '74 Challenger with original 360 and just had it gone through.   When we get it back all back together will have it on the dyno -- so not sure what it will be either.  Unfortunately, I didn't have it done before -- so won't be able to compare.   I believe they were originally rated at 245.... 

Vermont MOPAR

[SilverChally]

Guessing its an auto which takes away around 20%, so yor probally close to 280 number at the flywheel.

[inot2old]

Bob, I was always curious about that,  I thought it would be closer to 300 also.

[Jacksboys]

Look at it this way, it does not matter what it wil do on the dyno, but what it will do on the track.

[Chryco Psycho]

dynos virtually alwys leave you humbled , it i sia great tuning & comparison tool to see if you are winning or losing with the mods & upgrades you make & it can always find 20 hp tuning but the actual #s are generally low

[422STROKER]

230hp at the wheels isn't that bad.  Hows it feel?  If you don't race it, enjoy it.

Tom

[JS27N0B]

I don't think I would be too ashamed of those numbers. As stated above they were rated at 245hp when new at the crank. Figure in the 20% parasitic loss through the driveline and I'd say your looking better than stock.

[Mr. 440SixPack]

Sorry but 230hp and 270ft at 5000rpm is a lot for me The most powerful car in my town has about 150 hp

[CUDA JAS]

what are the specs of the moter?

Cam, intake, carb etc.

May be you can tune it for better power?

Liker was said above, if you are not racing it, that what does it matter, as long as you can  !!

[Super Blue 72]

dynos virtually alwys leave you humbled , it i sia great tuning & comparison tool to see if you are winning or losing with the mods & upgrades you make & it can always find 20 hp tuning but the actual #s are generally low

That reminds me when I went to Factory Five Racing in Wareham, MA, for thier kit car Cobra open house and they hand a dyno there to test out cars.  Keep in mind that these are cars that do sub 5 second 0-60, 1/4 mile in 13 seconds with a stock 5.0 Ford engine.  One of them had only 175hp at the wheels but it was still a fast car because the car was so light.

But still, that's probably more than what I have in my Challenger..... 


Wait a minute, so....if there's 240hp at the engine, what will it have at the wheels with an automatic?  192hp? 

[RDF]

230hp at the wheels isn't that bad.  Hows it feel?  If you don't race it, enjoy it.

Tom

It feels great, very powerful from 0-60.

what are the specs of the moter?

Cam, intake, carb etc.

May be you can tune it for better power?

Liker was said above, if you are not racing it, that what does it matter, as long as you can  !!

It's a 360 and from the paperwork that I found, it looks to be bored .30 over with a mild cam in it(no specs on the cam, but you can hear it when it runs).  Edelbrock Performer Intake and Edelbrock 600cfm carb.  I think the carb needs tuning though, it runs a little rich (you can smell it while idleing for a period of time).  Other than that, I don't know too much about the motor b/c I didn't do it.

I guess it's been that long for me (being into cars and motors) that I was expecting more that I got (as far as HP is concerned).  But as everyone else has said, it's prob. pushing close to 300 at the flywheel so it's pretty good for a muscle car not trying to be raced. 

[SilverChally]

If you want more power, do some head work.... thats where you'll get the 300 you want.  Theres guys deep in the 11s with j heads.

[TrakHor]

For what it's worth I had a Dakota R/T and when stock before any mods dynoed at 200 hp at the wheels. It was factory rated at 255.  Here's some factors to further compare by. That was a loss of ~21%, but the automatic overdrive it know to kill a little power.  So you probably dont have a auto over drive, but you could have a weak trans or torque converter these can all affect the rear output number. Did you do a tune up before going cap rotor and wires can account for some as well as plugs? If you get a wide band o2 sensor from some place like inovative you can tune your carb in and get it right before going back. Still you are real close to 300 hp at the crank.
The innovative piece isn't complicated to use, it's just a wideband 02 sensor. You can put a bung in each bank and move it from side to side to get each bank in tune, assuming you have dual exhaust. A 94 and up Volvo 850/S70 oil pan drain plug will work to plug the opposing bank. If you don't want to drop the money som vacuum gauge tuning could probably help the rich condition. As another member replied, the dyno can be a humbling experience, but there are a lot of little things that can be done to improve the tune on the car, then go back. If you put a hundred dollars into a tune up and a little effort on tuning you might see 245 at the wheels. 245 is close to 250, and a good % greater than what you started with.

Just my .02, good luck

[GoodysGotaCuda]

For comparison, my 318 was 240rwhp/270 ft/lb at 6000ft density altitude on a STD dyno with a 130,000mile tired 904 turning the tires at 144mph with the 2.76s lol, anda out of the box eddie carb. Does your chart say SAE or STD in one of the corners (or anywhere on there). STD is current conditions, SAE is corrected to sealevel. (mine corrected was 285rwhp if i remember right)




here is the chart, 6000ft conditions