dyno jet?

[duke1n]

Oh man I thought you were going to come back with some air density calculations proving that there was no more than a 6% density loss at any elevation with a turbo?

So why is it then that even the fuel cars when they come up here to Denver drop off substantually and only run comparable times by over driving their chargers and adding more nitro? I would think if anything could be reletively less effected by elevation and air density loss it would be a fuel engine that is moving gobs of air and fuel?

PS you seat of the pants meter is probably skewed by the lack of oxygen to the brain at 6000' lol

[Timbeaux]

I'll do you one better... I wanna see somebody that used one of those over 6% calcs actually do as well as they proclaim down here.

Mike, out of curiosity what CF did you guys use at GAM

[duke1n]

Where's Burner? We're talking dyno speak now so maybe you can jump in?

[duke1n]

Tim, I believe it was around 10% last year... not sure this year what it was. The interesting thing is my truck last year with a B1, Comp, and M4s did 514 corrected. That's pretty much in line with what that setup does down low. My current setup with the same Comp but with M6s and a 64 did 580. There again that's pretty much what a similarly equiped truck would do down low. Pretty sure from everything I have seen and heard from Don was that a decent ETC pump with a Comp and M6s is a 600hp truck. My was only 580 on the load dyno but will hit 600 I would bet on the Dynojet. It did occur to me one reason why the Superflow might not show as high a number using the same CF as an inertia dyno... heat soak. My truck fell off 20hp on the 3rd and 4th run. By that time the motor was majorly heat soaked after doing full boosted pulls from 1600-3200 over probably 10-15 sec timed runs.

I had this argument with Greg last year lol. So if you think that my setup is not close to 600hp and closer to the uncorrected 525 or so then I'm going to go complain to Don that his M6s suck and I want my money back. Brady's turbos must not be worth a crap either. We won't discuss the value of an Edge product lol. Any one of you low sea level guys come on up to Dieselfest this summer and we'll see what times you run up here compared to down there. I'll buy you dinner and your dyno fees if you can come close to your sea level numbers up here uncorrected. Takers?

You know why they call the Superflow dyno the Lie Detector? Go run on one and find out

[Timbeaux]

Ted Kobi Dynoed 544 with M6's and a Phat shaft... Not sure of the elevation or CF though. He also has a slushbox.

[duke1n]

What box?

[Timbeaux]

Comp

[Burner]

I don't know why you're call'n for me... unless ya just got the sweets for me?

David Dunbar is who ya need here. He is 'tops' for running a Dyno-Jet correctly.

[duke1n]

Must have been an ETH pump. Hard to get much over 540 out of them things no matter what shower heads you have.

I'd be interested in hearing David's comments on interia vs load dynos. I don't really feel this way or that about either one of them only can tell you what I have seen when running on both of them...

[Burner]

I'd like to see BDMAX or Kennedy post some up/down numbers. There are several trucks that have run both @ sea level and up there.

[Timbeaux]

Originally Posted by duke1n

Must have been an ETH pump. Hard to get much over 540 out of them things no matter what shower heads you have.

I'd be interested in hearing David's comments on interia vs load dynos. I don't really feel this way or that about either one of them only can tell you what I have seen when running on both of them...

I think his truck is an ETC, it is a stock auto. His Comp may not be a drag comp though

[duke1n]

Did he race that truck? What sort of times did it do?

[Timbeaux]

He used to race that truck, but it had a waaay diffrent setup then. I believe it ran 12.8x's back then

[DavidTD]

hmm,

Lie Detector was first used as the name for my Dyno Jet in 2003. When Kennedy started calling his SF that I didn't care and dropped the name for mine.

There will be a loss of power in Denver from Atlanta. I expect though tuning would recover some of that but I have no proof.

Hot humid conditions can be just as costly as altitude IMO.

In the Smokies this year, my dyno calculated a 5-6 % correction which I felt was too generous. At the end of the day I put my personal truck up that has a couple of dyno runs under it's belt. It normally runs 46xhp uncorrected/corrected at home. It ran 490 corrected and 468 uncorrected. I ran it at the strip there and it equaled the times it ran at home that calcualte 460's. That was enough for me to call the correction factor bogus.

I like both load and inertia. I like the Super Flow dyno. I don't agree with Super Flow's "estimated DJ number".

IF you are building a street/strip motor, I think it should be built to perform on a Dyno Jet. Drag racing is about acceleration, not placing an artifical load on the engine. Properly tuned on a Dyno Jet will then give you the same output on a Super Flow. Been there and done that enough.

Anytime you can't perform on a Dyno Jet, so far in my experience, there is tuning left to do. You don't take a truck like Morrison's, Garmon's, or Maddog's and make 100+psi (and equal road psi) and convince me there is not enough load. Not yet anyway.

I can't help but laugh when I read a Dyno Jet reads high or low. Because those statements always fly around but it can't be both. So everyone needs to agree, is it high or low.

[duke1n]

Agreed, I don't think either dyno reads higher or lower as a matter of design. What one can say for example here in Denver that the dyno operators here seem to configure the DynoJet so that it always seems to be 20-40hp higher than the Superflow configuration. That said the Dynojet is not generous because it's a dynojet, it's generous because the way it's operator sets it up. My truck will make a bigger number on the DynoJet than a superflow not less.

Load... Those trucks you mention David are compounds right? I've never ran compounds but it would seem they would be less affected than a truck with a big old single? My truck falls on it's face a bit on a Dynojet taking awhile to get things spinning. On the Superflow it can sit there and apply full load at 1600 and get the turbo going before it's off to the races. In the end it seems all dynos are really good for is doing relative measurements on the same truck and even those comparisons are relative to the conditions on different days.

Somewhere in here one could derive the magnitude of change in air density relative to elevation, temperature, and relative humidity. I'll hurt my brain later tonight and figure it out.

http://wahiduddin.net/calc/density_altitude.htm

[Dockboy]

Michael,

There is no "setup" on a Dynojet As long as the rpm is reading right, the hp/tq is what it is. The only thing that can effect that is what the weather station determines the CF to be. Otherwise, the uncorrected numbers can not be effected by any "setup", only by operation.


David, I need to do some tuning on your dyno sometime!!! My Dynojet numbers are consistantly 100 hp lower than my trap speed calculations!!!

[Timbeaux]

You run a Phat shaft 64 correct Mike?
If So, you will be okay on a dynojet. Jeff regularly whoops thrucks ino shape with SP 66's on a dynojet

[duke1n]

Yup that is what I meant Greg. Where do operators get their current atmoshperic conditions when deciding on a CF? Seems like if they setup in the morning and try and determine an daily average then running early would be adventagous while temps and humidity were down?

Yep Phatty 64

[Timbeaux]

The DJ software has a weather station of sorts

[duke1n]

That explains a lot lol