Dynapack = CRAP

[Carter05xb]

Tests don’t lie:

Mustang dyno's require you to manually enter vehicle weight and environmental conditions. Therefore either inflating or deflating dyno numbers are possible. The real benefit to the Mustang type dynos are their ability to put a load on the car and as others have said, simulate real world driving conditions for tuning purposes.

Dynapacks are sort of the worst. But are extremely portable and assuming conditions don't change, should still provide you with accurate representations of power gains/losses. They require manual condition inputs, and cannot generate significant loads or simulate real driving conditions, so Dynapack and Mustang numbers often quite differ. Meaning Dynapack is unrealistic for real world numbers.

A Dynapack removes the tire issue by connecting directly to the hubs. This, again, is unrealistic because the tire acts as a moment arm, and going to a smaller tire will yield more torque at the ground. Since you test on a Dynapack with the wheels and tires are removed, you cannot measure the difference you get from one wheel/tire size to another. Also, you have eliminated rolling resistance from the equation.

A Mustang dyno seems to be the most technically accurate. It can apply a load to the rollers and simulate a real quarter mile run, or any other run you feel like programming into the thing. There is still the unrealistic contact patch issue, but it is my understanding that no other issues exist.

I also know that Mustang dynos yield the lowest numbers of the group, which doesn't do any good in terms of bragging rights, which is what we're all here for anyway, right?

Seems to me that if real world performance is your primary concern, you should get your horsepower tested on a Mustang dyno. If getting the highest numbers is your primary concern, you should get your horsepower tested on a Dynojet.

Dynapack's marketing focuses mostly on explaining how it's better than Dynojet, but they have very little to say about the Mustang dyno, which tells me that even Dynapack knows they have nothing on the Mustang system.

Look below at the two dynos produced by the same car. I look like hot shit from the dynapack but look like a chump on the MD500.

So for those of you using a Dynapack thinking your king. Think again. Anyone using a MD500 or 600 that puts down the same as you or close to you will destroy you on the street.

Numbers don’t lie.

304.9 Dynapack
266.00 MD500

Conditions for both pulls were as follows. 86 deg. And 2500 ft. above sea level.

Don’t want to hear someone wine about conditions.

[PETERPOOP]

You should know every dyno is different. They are all calibrated differently. I got less numbers on our local dynapack than I did on the local dynojet. I also read different numbers between the two dynojets I was on. Weather conditions weren't much different.

btw, seems like you're a little bitter about this topic.

[cali yaris]

which doesn't do any good in terms of bragging rights, which is what we're all here for anyway, right?

Nope. That must be another forum.

[Carter05xb]

Not bitter. Just seen one to many people talking like they got great numbers and you come to find and see they use some cheap dynapack. That seems to be the local favorite of all wana be shops. Just seen to many other forums with guys acting like there all that and practicaly have the same set-up i'm using and produce unrealistic numbers. which is why I put up both sheets. I like to keep it real. Apples to apples. Don't tare off all your rotating mass and have no load to compare your results too. Even the guys at Dyanapack know they got nothing on the MD.

Just thought I'd come here and get away from the usual forums and spread the realistic version on the dyanapack.

[Carter05xb]

Everyone likes to brag when they get good results. look your doing it right now!

357 whp @ 24 psi on pump gas!
www.microimageonline.com

[cali yaris]

ok Mr 6 Posts, whatever you say.

[KCALB SIRAY]

...what if I stuck a 24" fan in front of the car instead of a 32", would that make a difference?

[Carter05xb]

Ouch, did I strike a nerve? It's ok to brag a little about your numbers. I think my numbers are good, I don't have the highest hp 1nz-fe out there but I'm satisfied. So unless your that inflated guy who only uses the Dyanapack to test on this topic shouldn't offend you.

The guy that has the xa seems to be on the money with hp. Perhaps a little high on the dynojet but atleast his wheels are on.

I just seen your build is on microimage, Cali Yaris. Cool I'm gonna check it out.

[thebarber]

i thought everyone knew that mustang dynos gave lower #'s than dynapack or dynojet...?

[Carter05xb]

I know the MD produces lower numbers, however they're realistic. Which is what my point is. Running a dynapack is about as bad as getting a car from the dealer saying it has 500hp but it's to the crank. Which then turns into damn I only really have 375hp. That's all I'm saying. Keep it real.

[PETERPOOP]

Get over it, seriously. lol

[cali yaris]

^ yeah really. You can't compare one person's dyno to another, period. It's pointless.

To me, the number doesn't matter at all, the only thing I care about is numbers before and after a change I made, done on the same dyno.

I built my car to race it, not to have a number to advertise. It's not a dyno queen, like some other builds I know about.

[Carter05xb]

I was simply showing the differences between two. No reason to get so huffy. If I were trying to be mr. Cool I'd only show the dynapack dyno numbers. Just thought people should see the real difference. Now I see why your getting so defensive Cali, with your rmarks towards me. You dyno'd on a dynapack! You should still be in the high 200 to 300hp range on the MD. Either way you have a nice ride. Enjoy your rides guys, I am.

[cali yaris]

Thanks for showing the differences. You did that in the first post. So we're done right?

[Carter05xb]

Of course we are. I proved my point between the two. If anyone should of been upset, it should of been me. But hey I now know the realistic road conditions vs. The not so real. I wasn't looking to have some lengthy debate over dynos. I got that in my hands already.

Movin on guys

looks like a few of you got nice rides here.

[Jason@SportsCar]

Dynapack is generating a flywheel power number, based on power measured at the hub.

Mustang and Dynojet provide power at the wheels.

Depending on the car (drive train layout) you can plug in a 10-15% loss (flywheel to the wheels) and both machines are right on the money.

Apples and oranges, but both get the job done. We have used all three models extensively over the years. I will take a Dynapack for tuning every time... It is way more sensitive and repeatable when making small changes - not as good as load cell dyno, but its also nice not having to pull the motor out.

Kind of a pointless rant. Wow, these two things are not alike.

[ilikerice]

AND now we are done.. hahaha

[KCALB SIRAY]

...what if I use hot air instead of cool air on a cold day?