High stall converters and dyno's, is it worth it??

[TC]

Re: High stall converters and dyno's, is it worth it??

And WOW only about $40,000 for a DynoJet Auto dyno with all the bells and whistles.

Almost makes me want to go out and buy one. I bet they have financing plans. ;)

[SpiderGearsMan]

Re: High stall converters and dyno's, is it worth it??

the only water brake dyno was donated to my college
with a 350 diesel
me and sherm decker promptly broke the water brake
the chassis dynos we used at ny state inspections were crap , and flying wheel weights and broken tie down straps have killed a few guys
in nascar and pro stock - dyno is critical , on a street car , you have to gauge total vehicle performance , seat of the pants for the street , ET s for the track

[JeffMcKC]

Re: High stall converters and dyno's, is it worth it??

I dont know that you would call my 6000 stall high,,, when Doc runs 6800 in his big block, but we have both found HP on a Mustang Dyno, with tune help from Scott, then we read plugs, and change heat ranges, and come up with more every time the Dyno has helped, but we are not compairing ours to someone elses, just looking for a bigger number from the time before.

[BlackoutSteve]

Re: High stall converters and dyno's, is it worth it??

Steve - Never used a hub dyno but the concept certainly has merit. Is the Dynopack a water brake, Eddy current, or ??? Any pics? When I wrote my dyno article I researched them a bit but was unable to find anyone with hands on experience. Evidently I've never lived close to a facility that used this device so I can't track one down. I would certainly be willing to run the Buzz Bomb on one if it was available.

Dan

As I've mentioned before, I used a Dynapack hub mounted chassis dyno. It knows engine speed via a spark plug wire sensor, and knows wheel speed on it's hub. So knowing how much the converter slips is a no brainer..

I assume you've seen their website.. http://www.dynapack.com/index.php?op...tpage&Itemid=1

The "contact us" link will show the US ditributor. No doubt they will know of someone close to you with one.

Because they're so portable, many of the V8Supercar teams carry them on tour. As far as I know, some NASCAR teams do to.

These are over 10 year ago now..

http://www.youtube.com/watch?v=RJtV5shYoAs

http://www.youtube.com/watch?v=_WiS_o007Ew

Also, the results on my graph where the converter was slipping (below 3500) were also a little confusing.. We started the pulls from 3500 onward. I'll see if I can look them up.
They are incredibly sensitive units. One of their boasts is that they can be measuring a steady state (fix rpm) of 600 or more hp and see when the headlights are switched on via alternator load!

[TC]

Re: High stall converters and dyno's, is it worth it??

One of their boasts is that they can be measuring a steady state (fix rpm) of 600 or more hp and see when the headlights are switched on via alternator load!

Speaking of that anyone know how HP an alternator robs.

[squirrel]

Re: High stall converters and dyno's, is it worth it??

because of the time required to build a set up (remember, I'm not running a SBC)

At least the mounts/bellhousing/flywheel flange are SBC....

[dieselgeek]

Re: High stall converters and dyno's, is it worth it??

And WOW only about $40,000 for a DynoJet Auto dyno with all the bells and whistles.

caution, that's a junk level dyno. you're spinning a drum of concrete. Unless they dropped the price of their "pseudo-real" dynos by $40,000 in the past year.... that's just an inertia dyno. No good for fine tuning... (IMO)

[JeffMcKC]

Re: High stall converters and dyno's, is it worth it??

Hey scott answer your phone LOL

[dieselgeek]

Re: High stall converters and dyno's, is it worth it??

Hey scott answer your phone LOL

the number you are probably calling, is my home phone... calling you from my mobile now.

[greenjunk]

Re: High stall converters and dyno's, is it worth it??

Having seen and made a couple 1000 dyno pulls, I have to agree. It is mearly a tool for determing changes. It is what it is good or bad. Most dyno jets run pretty close to the same output number, accurate or not, they seem to give you the same number (test same car on several dyno jets in different areas of the country). If you have a base line, whatever the number will be, any changes you make will either be better or worse. That said there are many ways to "trick" the dyno to give you whatever number you want. just take a heat gun to the weather station, and put it on a correction factor setting and a honda civic can make 500hp. Its however you use it. I like them because I know my tune is generally safe, or not safe, but ok in most cases ;D. The true test is how it performs on the track. i've seen 425hp cars beat 500hp cars on the track as tested on a chassis dyno. Its only a tool its your job to take the data and use it appropriately. So I guess a dyno is only as good as its operator.

[TC]

Re: High stall converters and dyno's, is it worth it??

And WOW only about $40,000 for a DynoJet Auto dyno with all the bells and whistles.

caution, that's a junk level dyno. you're spinning a drum of concrete. Unless they dropped the price of their "pseudo-real" dynos by $40,000 in the past year.... that's just an inertia dyno. No good for fine tuning... (IMO)

It would be for this model right here.

http://www.dynojet.com/automotive_dyno/224xLC_dyno/default.aspx

[dieselgeek]

Re: High stall converters and dyno's, is it worth it??

looks like sketchy marketing to me. It has an eddy current motor (TINY one) and says "will do load tests" but then it goes on to say "will measure 1500hp and 200mph"

it'll probably do 1500hp with the usual inflated dynojet numbers, or maybe 300-400 in loaded mode. Which is still a lot better than what they used to sell for $40,000, but I'd still look into why Superflow, Mustang, Dynapack, etc. cost so much more...

[DanStokes]

Re: High stall converters and dyno's, is it worth it??

Dang - you guys got ahead of me - been out banging on the Buzz Bomb, then a Neighborhood Watch meeting. Anyhow -

Dynos have and haven't changed.

The basic Clayton-style water brake (hydrokenetic) chassis dyno is still pretty much the same old animal with a fancier saddle. As stated, most differences are in the software. I haven't researched it but I think that's what the Superflow chassis dyno uses - and so does their engine dyno, which I have messed with extensively. BTW - water brake PAUs have a definite service life which can be extended by carefully controlling the water quality going to the PAU and to the cooling system

Eddy current dynos remain pretty much the same other than improved sensitivity. I'm not sure how much of that is software and how much has to do with better cooling control, etc, but I'd guess some of each. They remain unable to negatively load a vehicle or engine (think coasting down a hill) but for what most of us want to do this doesn't matter.

Inertial dynos remain pretty much unchanged other than improved software. The deal with inertial dynos is that they basically don't measure squat other than the time required to accelerate a heavy drum. Some of the newer inertials include (as mentioned) a small eddy current PAU (power absorbtion unit) to impart some load at steady states. They could use a water brake but I don't know of any that do.

Now for the Mac Daddys - DC dynos (the Grandpas) and Flux-Vectored (or phase-angle shifted) AC dynos. These can be either chassis or engine configured and have the ability to both negatively and positively load the test subject. Both can simulate ANYTHING an engine or chassis system may encounter. If the software is smart enough, they can even simulate a trip around your favorite race track, with shifts if you have the right info taken at the track in question. This ability comes partly from the speed and flexibility of the dyno itself and partly from the amazing software that supports it. This technology changes at lightening speed and it's almost impossible to keep up with it now that I'm no longer dipped in it daily.

Your question - have dynos changed? The Flux-Vectored units didn't even exist when I started doing this work. They are faster, cheaper, easier to run and program and require less maintenance than the old DC units. Faster is always better with a dyno, except - our AC's were SO fast that they would break driveshafts. We had to slow down the response rates to be more like the DC units to keep the dyno hooked up to the engine. So in this case, yes dynos have changed a lot, depending on the type in question. But they can't change too much as the required simulation - the necessity to overcome the inertial load of the engine/vehicle and to simulate the road load of the vehicle (an overly simplified term) - remain constant.

FYI - a fully equipped test cell with a Flux-Vectored AC dyno, the computer to control it, and instrumentation to run it - something like $5 to 10M. I'm guessing a chassis cell might be a bit more (I wasn't involved in a chassis cell procurement). That doesn't include the room, air handling equipment, appropriate fire protection, etc, etc. You don't see too many of these for rent to race teams.

How's that for "more than you wanted to know"?

Dan

But you do have to say dyno's have changed over the years. Like how different did they get from the time you started using them to the time you stopped.

[horsewidower]

Re: High stall converters and dyno's, is it worth it??

I've used a Mustang and a Dyna pak. The nice thing about the Dyna-pak was that with the adaptors directly affixed to the hubs, you didn't have to worry about having the car try to climb off the dyno.

When I went down to a class at EFI University, I had the opportunity to observe a Mainline. What a nice piece. Had a neat piece of software wherein you could do some timing sweeps at a steady state and the computer would tell you which timing gave you maximum brake torque.

I've heard good things about Dyno Dynamics, but have neither observed nor used one.

If the dyno won't do steady state, its a waste of time.

I'd really like to pickup an engine dyno, I'm tired of thrashing the car on a chassis dyno.