Dyno Results

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roccodart440

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After making some passes at the strip and not being where I wanted to be I wanted to get a baseline on the power I'm making. I headed to the local chassis dyno..

3 dyno runs. No tuning was done. They were all pretty much the same as expected.

BUT....

The results kind of surprised me.

299-310hp

425-450 ft/lbs.

Car seems way to fast for those numbers.

He said the numbers were typical of a good running big block car.
 
If you don't mind saying - what is the build?
As for comparables -
1. The last mildly built 440 I had on rollers was past you by 75hp and 30 pound feet. All iron, mildly ported heads, hydraulic cam, 6bbl, and headers on pump gas.
2. My most recent 496 has you by 149hp and 43 pound feet with ported Stealths, hydraulic cam, and factory exh manifolding on pump gas.
 
If you don't mind saying - what is the build?
As for comparables -
1. The last mildly built 440 I had on rollers was past you by 75hp and 30 pound feet. All iron, mildly ported heads, hydraulic cam, 6bbl, and headers on pump gas.
2. My most recent 496 has you by 149hp and 43 pound feet with ported Stealths, hydraulic cam, and factory exh manifolding on pump gas.

440, 10:1, Eddy RPM heads and intake, [email protected] / .528 slid cam, TTI headers, 950 carb

Car goes 11.70's @114 in full street trim on street tires through the mufflers.

Weight unknown at this point.
 
Don't get hung up on dyno numbers.....though those are nice torque figures. Just keep tweakin it faster at the track. The track IS the only dyno that matters. When all the other numb nuts brag about their dyno numbers, whip your time slips out and shut them up.
 
Chassis dynos are, of course, valuable tuning aids but as they say," We don't race dynos". You shouldn't compare your results on a chassis dyno to someone else's results on another chassis dyno. http://www.hotrod.com/how-to/additional-how-to/hrdp-0405-chassis-dyno-guide/

^100% truth. Some dyno's are happy, some are sad. After running a chassis dyno for a few years, it all depends on how often they are serviced, what kind they are and the operator. Yes, the operator can skew numbers. Things get trickier with more modern cars with traction control and other drivers aids.
 
Don't get hung up on dyno numbers.....though those are nice torque figures. Just keep tweakin it faster at the track. The track IS the only dyno that matters. When all the other numb nuts brag about their dyno numbers, whip your time slips out and shut them up.

Reality, at the rear wheels.......
 
Honestly, I'd screw those chassis numbers...Your ET's & MPH show more power to me then those numbers. The 114mph alone @ 3300lbs is way more stout then those "chassis" numbers. Are you totally efficient, I don't think so, but that session is not giving you a true picture of what you're really making...imo. Is there some power on the table with your combo, probably, hey, there always is...:).

ET wise, it's always about the cam, converter & gear, no matter what the engine.....Depending on the latter of the two, I think the cam choice here could be the deciding factor for you. That cube/head combo can make some big power, but if you're comfortable with where you are, just enjoy it. After all, It is a really fast car as is. :thumbrig:
 
What car is it again? A typical no roll bar, aluminum head BB, full interior, full exhaust street A body will go around 3300-3400. Gearing, convertor, and suspension effectiveness can make up for a lot. All this really means it the torque is what's making it be quick, and going by the numbers you're probably looking at a stingy chassis dyno. What's your lash on that cam?
 
what trans / converter do you have in there roc

727, Art Carr 3500 convertor

What car is it again? A typical no roll bar, aluminum head BB, full interior, full exhaust street A body will go around 3300-3400. Gearing, convertor, and suspension effectiveness can make up for a lot. All this really means it the torque is what's making it be quick, and going by the numbers you're probably looking at a stingy chassis dyno. What's your lash on that cam?

No roll bar, aluminum head, BB, full interior, full 3" exhaust with borla XR-1's

4.56 gears

The guy flat out told me find a guy with a dynojet chassis dyno and you'll see 50-60hp more.

Lash is supposed to be .028/.032. I set it .024/.028.
 
I managed a dyno place for a little while years ago with a Dynojet. It's calibration, correction factors, and data point smapling that determine the outputs. Use the data to plot trends because that's about all they're good for. Especially with a good torque convertor.

How tall are your tires? What rpm are you trapping at?
 
I managed a dyno place for a little while years ago with a Dynojet. It's calibration, correction factors, and data point smapling that determine the outputs. Use the data to plot trends because that's about all they're good for. Especially with a good torque convertor.

How tall are your tires? What rpm are you trapping at?

28" tires

114 trap speed with a 25mph headwind.
 
What is the rpm? Also - do you have the incrementals for that 114 run?
 
Looks like a tight convertor and a torqie engine alright.
You're almost in line with a buddy's GTX 440. He was in the 11.60s at 115 with a set of my 915 heads, the .528, and a matched single plane M1. He ran 4.10s with a 27" tire. I'd tell you the same thing I told him: give it a little more cam. Another 10-12° @ .050 and another .050-.060 lift at the valve will help the upper end pull. It would also allow a looser convertor to quicken the 60 and pull harder through the lights.
 
Mopar, looking right now at ported heads, cam in the area you mentioned and a slightly looser convertor. Mine flashes to 3500 but you can't footbrake it at all.
 
This thread isn't helping my street/strip engine build keep street in the equation.
 
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