dynocar

Sorry to kick a dead horse by a late arrival, but just some comments to jammers original post.

jammer states,

"Dynojet and Mustang seem to be the dynos used by most shops, especially LS1 shops. After intense research and training on different types of dynos, I cant understand how and why we use these to tune.
Neither of these dynos can hold a load at a specific rpm, not even the Mustang with the brake. This was, in fact, verified at the Mustang manufacturing facility, so I know this is the case (brake pulses can not hold rpm steady enough), so while tuning is better onthe mustang than the dynojet, it didnt come close to the others in ability."

I think we are splitting some hairs here, such as, I disagree with part of the above statement. We have been using our Mustang MD-1750 with load control for five years full time, this is all we do. We CAN hold any RPM at different loads as long as we do not exceed the static load capacity of the power absorbtion units (PAU), up to 800 RWHP. The hair splitting here is true we can not hold, let's say, 4221 RPM exactly but with the normal 300-500 RPM resolution found in most tuning load/timing tables, we can get it well centered. However we seldom use this feature, it is good for roughing a tuning table in but this is NOT a good tuning proceedure. If you use that proceedure, then simulate the normal RPM sweeps for that engine's application, that tune will be off. When I discussed this with a rep at Mustang Dynamometer yesterday they stated that the above info about Motec's claim is misstated.

"In tuning properly, we obviously need to find max cylinder pressure and adjust A/F ratio and timing for each "cell".
If the dyno cant hold a constant load at a given rpm, under various amounts of load, can we really tune correctly on a dynojet or mustang.
My feeling is...No we can not maximize the potential and give a best case tune."

Again, you tune an engine as close as possible to the environment that it will be utilized, simulated sweeps for WOT and simulated loads for part throttle drivability which many of todays load bearing chassis dynos are fully capable of if the weight and air drag factor of the vehicle entered. If this was an industrial engine that just sat at one given RPM with different loads, then I would agree. Tuning each "cell" is too time consuming and totally unnessesary for a good chassis dyno tune in a reasonable period of time, engine wear and consumer affordability.

"The two types of dynos that I found to allow us to tune "to maximum effort" are the Dyno Dynamics and the DynoPaks."

Given what I've already stated and from a tuner's perspective, what can those dynos do that most of the Mustang or Superflo chassis dynos cannot. With our latest software update, outside of wind tunnel simulation, what am I missing?

"Go ahead, defend...or comment please."

My comments - I don't think that most people realize how much can be accomplished in a short period of time with a good load bearing chassis dyno operated by an experianced, knowledgable dyno operator. For ten years we cut our teeth on a Clayton manual controlled water brake chassis dyno. There is were we learned the value of load control. Then we moved to the computer controlled eddy current load cell. What an improvement, now we have tuned hundreds of cars that customers report dramatic performance increases at the track, not to mention finding problems for these people on the dyno that many could not find on their own. C'mon guys, lets appreciate what we have today, maybe not perfect but dam good.

Rick@Synergy

iTrader: (5)

I look at it this way...I tune on a mustang dyno only now. I like that dyno, works great, great road simulation, ect. But the problem I have is its not mine. So when I am thinking about buying a dyno, I have to look at a few things.

1. I dont have the room for the mustang dyno. So this is where the dynapack comes in handy for my shop.

2. I am doing alot of FI cars, and most are turbos. I like the ability to go RPM by RPM if I need to. Now I never tried it on the mustang yet, but I dont doubt the mustang can do it just as well. Like you said, a good operator on the dyno is needed.

3.My shop insurance out here in Cali is way expensive enough, if I use the dynapack, it wont raise the insurance at all.

So because of my requirements, I am most likley going with a dynapack. I dont mind sticking witht he mustang dyno because I have had nothing but great results with it. But when you spend enough time and money on someone elses dyno, it just seems better to put that money into your own dyno payment.

So in my conclusion, Dynojet I will never get on again. The mustang Dyno is by far one of the best I have been on. And the Dynapack is great for my needs in what I want to do and what I have to work with. I never been on a DynoDynamics yet, so not sure. Havent tried the superflow either.

Rick

Redline-Motorsports

iTrader: (3)

I agree with Rick on his view of these new dynos. I am also getting ready to make a purchase and after spending a day on a DynaPak "steady state" dyno I am sold on its ability to really control load. We tuned a turbo Mustang and it was amazing to give detailed attention to the 1600-2400 rpm mid load area. We saw 40-50 RWFt after playing with the timing at those areas, something you can't do on a DynoJet. For most cam/head 346 setups tuning can be easly done on a DynoJet 248 because the factory fuel and timing MAPS are pretty close and the most area is in mid and upper end. However you start tuning a 420 ci + big cam motor and the 1600-2500 rpm ranges needs some attention. This is also true for FI motors.

I like the DynaPak because you don't have to tie up a bay in the shop!!

Tomcat

Dyno dynamics is like a cross between the mustang/dynojet and a dynapack dyno.

They are a full eddy currrent dyno that you can drive onto and strap down intot eh rollers- 2 min operation.

Dynojet I have used and they are only good for doing a power run and it does not give you the ability to change the rate of the run to simulate the real world load of the car on the road - I would never use one to try and tune a vehicle on.

The only drawback to the Dyno Dynamics unit is its software - not as good and the DTS dyno or some of the Dynalog software in its storage and retrieval of data.
That said it is still far in front of the dynojet I used to use

dynocar

I am not affiliated with Mustang in any way, we have had our issues. But then again, I can't think of one supplier that have not had issues with, maybe its me. But having stated that, after considerable chassis dyno research and 15 yrs of chassis dyno experience, and now having had five years and hundreds of cars on our MD-1750, I would go the Mustang route again. My purpose here is not to convince anyone to buy this, there may be other systems as good or better, but hopefully I can help potential purchasers with some things to consider that they may not have thought of. This is from the hip, but here are some reasons why we purchased what we did and now glad of it, without bashing.

Manufactured/assembled in the States. Not only because I like waving the flag but also because of the extra level of support provided because of it. A load bearing dyno is very complex and sometimes requires some high tech attention. I've loaded up major assemblys and drove them to the factory for a quick repair, approx 1000 mi., and have required knowledgeable factory techs at our location.

HP capability. We have evolved into testing/tuning a lot of high HP vehicles such as modified Vipers, we have the worlds largest Viper dealer in our back yard. When our dyno was down for upgrades we rented some time on a smaller load dyno. After a few Viper tuning pulls, that dyno was smoking and we had to wait for cool downs. There is going to be some expensive maintenance costs if they keep that up.

Traction. We once had a dual roller dyno and were constantly fighting tire slippage and heat. Our huge 50" rollers simulate concrete.

Vehicle simulation tuning. The closer you can duplicate the load and acceleration of the engine the better you can tune it. If you change this, your optimum fuel and spark tables need to be reworked. After loading the vehicle weight and body air drag info, I'm convinced this works due to the duplication we see in drag race simulations on the dyno.

Weight capability. With the increasing popularity of gas/deisel truck tuning, those 10,000+ lbs of axle weight capabilites are needed with the trucks that carry extra fuel tanks, tools, covers etc.

Upgradeability. The MD-1750 can be configured as strictly an enertia dyno (priced competively with others), or single or dual eddy current load control. We only have a single and have never needed the second one (expensive) but nice to know we can always add it. We just upgraded our software, fortunately they are always improving their products.

Will they be marketing/supporting their products 10 yrs from now. Don't know, but I have had high tech equipment suppliers from other countries and often their in States support is inconsistant.

Bottom line, I have not seen a chassis dyno on the market yet that can do more then this dyno to fit OUR testing/tuning purposes, pretty good for a high tech product that's now five years old.

Rick@Synergy

iTrader: (5)

Thats cool. I wasnt trying to make it seem like you only like the mustang dyno. Hell, I like the mustang dyno myself. Thats what I currently tune on also. I was just wondering what would work for me because of my limited space. I just want to know the Dynapack will do what I want it to do. If I had the shop space, it would be a Mustang Dyno.

Rick

Tomcat

My Dyno Dynamics dyno is out of the ground and there is even a new option with wheels so you can wheel it into a corner out of the way when not needed - unfortunately mine is used continuously so it always takes up a bay



Thats my old shop , we have sinced moved and the dyno is very easy to move around - we take it to shows etc on the back of a flat bed , takes about 1/2 hr to setup.

Traction is not a issue , we have personally run up 900 rwhp no problems and the same dyno is uses at the summernats car show here in Australia where they have held down 1500hp street cars on full load

Rick@Synergy

iTrader: (5)

Thats pretty nice looking. I like how its low to the ground. I bet it wouldnt be that expensive to put it in ground also.

Rick

Tomcat

I decided to leave it above ground as it makes tying the vehicle down into the rollers so much easier and more effective and it can be moved around easier , I got sick of trying to ly under cars to strap them down.
On high HP cars I use a strap that runs under the dyno and up between the rollers effectively pulling the car straight down into the rollers , as the car loads up more it tries to drive out of the rollers but the belts effectively pull it harder onto the roller and traction gets even better.

Having used a lot of dynos much like yourself before I purchased my own I would never use a inground on again , also if I need the space I just roll the bed into the corner and stack the ramps , I can get very low cars up onto it no problems.

Also when its up against a back wall with a extraction system behind it you can still move the ramps and have a 3/4 bay anyway to work with.

I can do front wheel drives just by pressing reverse on the screen.

I like the dynapack system as well but the setup time is too long - I havent used a mustang dyno as we dont have them over here but the dynojet I used to use was also a long setup time trying to get the car strapped in the centre of the roller.
With my setup I just back the car on into the rollers , clip the strap onto the lower wishbones , tension , insert a chock in front of the front wheels for safety and start tuning - all of 3 mins

I also like the dynamic test system dynos which are very similar to the Dyno Dynamics unit.