This is also very true. I actually didnt buy my dyno for numbers, I wanted a usable running car in the end. I want a car that responds in every situation. Its funny if you talk to the guys from dynapack and ask them how you do hp tests, and from how they talk, they didnt realy design the dyno for that purpose either. Its more of a real tuning tool the right way IMO. So since the internet is full of "How does that cam sound?" and "What kind of power did that cam make?", you can see where the dyno is being missused.

rick

 

I question how much professional dyno shop experience some of the posters really have had here, a lot of theory but questionable practice. I do not agree with many of the statements being made. I wish I had more time to address every issue but I'll address a few. I cannot properly tune a vehicle by stepping it cell to cell at a steady state. Our dyno, contrary to other posters, is very capable of this, but this proceedure is wrong. Breifly, a combustion chamber will burn differently during a quick RPM sweep at 100 kpa/6000 RPM then if held there. Many times I have tuned steady state, cell to cell, only to have to make dramatic tuning changes when doing an actual vehicle simulation, such as a drag race. Also, not many race engines can hold up to such unrealistic, time consuming tuning. Next, we CAN very, very closely simulate a drag race application with our Mustang MD 1750 chassis dyno. With the weight and air drag factors entered into the computer, it applies the load accordingly. We have compared these results to actual data logs from the track. With the exception of 60 ft times, the engine sweeps, ETs and MPHs come out vary close, as close as the racer going from race track to race track. If these posters had years of experience running a dyno shop, most would not suggest that a dyno is a money pit. Like many service based businesses, scheduling, chargeable hours, etc. are very pronounced with a chassis dyno shop. Example, it's raining this week, how many appointments will not show? We have a three week backlog of people begging to get in but dam the no shows. I know many dyno shop owners but few are getting rich from it, more have gone out of business. These posts remind me of talking to the personel at the dyno factory, there solutions make it obvious that they have never had much experience running a dyno shop, all theory.

 

Like I said before, I like the mustang dyno. And judging from your posts, you do too, thats why you choose it. In fact, I use a mustang dyno every time I tuned before I got my dynapack. Granted yes you cant always tune cell by cell, but you can actually get closer I think. I find that when a car knocks during a sweep test, its because nothing is smooth and the transitions between timing in one cell is far off from the next. Or air/fuel is doing the same. Thats hard on the sweep test as well. But I just find it easier to realy see if there is anymore power to be made in certain areas of the car with this dyno instead of others. I also like the idea of not having any tires/rims or other variables affect the numbers. With the wheels off, every car becomes an equal.

Again, I have nothing against the MD, I use it all the time as well. I have had awsome results with it. Plus your right about the 1/4 mile sim, its pretty damn accurate.

Rick

 

No, I am not "pro" Mustang Dyno, I am "anti" misinformation, a Superflo, or other brands of load bearing dynos would probably satisfy our needs. When I read that we can only do this with my kind of dyno, you can't do this with other dynos or this is the best way to do something, when I personally disagree, sometimes, maybe unwisely, I state it.

 

IMO a vehicle should always be tuned to the situation in which it is going to be used. Some vehicles should be tuned cell by cell especially if it is going to be seeing street use. On the other hand if you are tuning a Top Fuel car I highly recommend ramping. For the soul purpose that if you were to hold a Top Fuel car at any rpm for a substantial amount of time your risk catastrophic damage. There really is no way to tune cell by cell because of constant variables, such as hot spots that are produced in the combustion chamber.

When it comes to a dyno I feel that each serve there own purpose. You have to realize that alot has changed in the last 10-15 years when it comes to dynos. Most of them weren't design for tuning fuel injected vehicles they were designed to analyze power at different curves. Mainly carbureted or manuel injected vehicles, where you wouldn't be able to make a change until after your run was complete.

Now things have changed and so has the way in which we use the dynamometer. It wont be long before OBDIII hits the market place and a lot more thinking has to come into play.

Sorry I just took off rambling...it's late and I just finish the work I had to take home.

 

Another good point. But I find that after checking the Air/Fuel RPM by RPM, then I do a sweep test, it runs better because the A/F is where it should be and when it ramps up like on other dynos, the curve is smoother and easier to adjust.

But with Top Fuel, thats why they never dyno those motors. They dont hold together long enough. Never meant to dyno. Just run once.

Rick

 

Rick@Synergy- Most Top fuel vehicles are actually dyno during there break in period. This is the best way to break them in and perfect what you have assembled. Being of course and engine dyno not a chassis dyno. By the way...Top fuel motors do have more life to them then you would expect. They just require constant TLC.

 

Most engine builders I ever talked too told me that there is no point in dynoing them due to life span. But thanks for the info. I know they need alot of TLC.

 

i didnt know there was a dyno that could take 8,000+ hp

Please show me the dyno that runs these motors!!!!

Thats why its nice to have an open wheel racer, your power levels are not out of range for most dyno's

 

I have a Dyno Jet and am installing their new eddy current load control.
It is supposed to be able to control 1000 HP for stepped and steady state tuning.
I opted to spend the extra $20 for the very reason posted in the beginning of this thread. Tuning.
We'll see how it works in a few weeks. If it works as advertised, it will be a great addition to my shop.

 

I wish to appologize...I recieved an email that said that people had responded so I was looking at the responses (Now this is how lame I am) and I see the one that DanO has responded with and I say to myself. What the heck is he smoke Blown Alcohol don't make 8000hp. Then it hit me....this whole time I have been writing Top Fuel. MAN AM I A DUMB ***!!! I apologize everyone that has read this for my mistake.

By the way Rick, most Top Fuel (now I mean Top Fuel this time) I've seen are usually torn down after every pass. In fact I have even watch them be re-ring while still in its cage.




Thank goodness Ben didn't read this he would be giving me hell right now!

 

Out here in Australia most all chassis dyno's are eddy current type (i haven't seen an inertia dyno in 5 years).

The most commonly found are:

Dyno Dynamics - http://www.dyno.com.au/home.htm
- most popular
- put a lot of effort into the so called "Shootout Mode" which is a certification on software, usage and practices to ensure consistent results on all dyno dynamics dyno's

Dynologic - http://www.dynologic.com.au/
- generally regarded as a "premium system"
- very good software
- large rollers
- used by a few leading raceteams
- also make great engine dyno's

Dynapack - http://www.dynapack.com/
- bolts directly to rear axles eliminating tyre slip/pressure variables
- used for accurate results and repeatability
- can be used to test axle tramp and clutch performace, and some aspects of suspension dynamics
- very good software also

I've mostly used the Dynologic setup, both engine and chassis dyno's. However, i have done some stuff on the Dynapack and it is quite impressive.

In regards to tuning, it is sometimes very difficult to tune the light load area's of an SD tune on the chassis dyno as the resistance is just too high to get those "coasting along" cells in a VE table.

Anyway, my 2c.

Chris...

 

LOL, took me 13 years , a divorce, multiple deaths, a few kids, 17 vehicles and a buncha drunken bartenders , but finally ordered a dyno. Dyno Dynamics it is.

 

I saw the username and was like "This cant be right, Jammer doesn't post on here anymore????". Congrats on the dyno purchase!

 

Gotta say, this is unusual. A necropost - and it was actually relevant to the original topic and the original post!

Congrats on the purchase!

 

Some stuff remains the same. Had to go live life for a bit but never left the scene completely, just stopped talking about it. Back in the saddle.

 

Welcome back!

 

after using a mainline pro hub up to 1160rwhp through a big converter I don't think anything compares.

as much or little load as you desire, static loading, repeatable, no wheel slip

hands down best dyno on the market.......IMO