Wrong dyno?

[garrett]

I had a bad experience at a local car show today, and I thought I would share it with the rest of the members of the turbo Buick community. I am used to not winning anything at the car shows, either because people at prejudice against Buicks or they don't understand how our cars work. Also, it's almost impossible to make the engine compartment of a turbo Buick come out a clean and neat as a 50s or 60s muscle car. I go for the fun of it and because I am a fan of all cool muscle cars/hotrods/ and trucks.
My bad experience has nothing to do with getting slighted at the car show. This local car show advertised a mobile dyno for $75. I didn't think to ask what kind of dyno they were going to use. I paid the $75 and was the first car on the rollers this morning. I really wanted to see what my creation would do. It feels very powerfull on the street, but without a dyno sheet or time slip, nobody is going to pay attention or take me seriously about the car. I made several attempts to spool the turbo and went up to 5000 rpms. I could not spool any boost. The numbers were dreadfull and I told the dyno operator that it wasn't working. They tried to but the brake on the rollers and one other time I tried foot braking my car. I was only able to muster 12lbs of boost. I know my car will make 22lbs on the street easy. After about 30 mins, we gave up. The guy had a teen age son helping him out and he was trying to explain to his father that with a turbo, there needed to be resistance against the wheels in order to spool the turbo. The dyno operator couldn't understand that. He tried to say that there was something wrong with my car. I told him that he was wrong and I would prove it to him. As soon as he unstrapped my car, I went out to the road and ripped off about 4 23lb boost runs up and down the street. I could hardly keep the rear end under the car. I was mad because I had wasted my time and money and beet on my car for nothing. Nothing except I know now that I need to take my car to a Eddy current dyno, instead of a inertia dyno. The world just isn't set up to accomodate our turbo monsters. Feel free to chime in.

 

[Chuck Leeper]

" Nothing except I know now that I need to take my car to a Eddy current dyno, instead of a inertia dyno."

Sumptin wong.. There are literally 1000's of inertia pulls made on TR's, and maybe 200 on mine, alone. Boost is never a problem. Turbo cars do not require an eddy dyno to be tested.
How was the test conducted?

 

[garrett]

?

I don't know, It wasn't my equipment and did didn't run the machine. I just operated the car.

 

[garrett]

dyno

I remember seeing something in one of the GS-XTRA mags about how one of the kinds of dynos is wrong for our cars. The one I tried today didn't work.

 

[Slow91z]

I have used both and both worked...But never a mobile version maybe the drum on the mobile version is to small and basically the car was coming up on redline before it spooled.

 

[V6POWER]

On a dyno you usually just do a pull between certain mph's or rpm's. I typically do a pull from 70-120 mph. I just start driving on the dyno, increasing my speed ensuring that I am at WOT by the time I hit the speed that begins my 'pull window', in my case that is 70 mph. I continue at WOT until I hit 120 and then let off the gas. You don't try to build boost at the lower speeds but you should be at max boost when your pull window starts.

 

[garrett]

no boost

I reved it up to almost 5000 rpms and got no boost! Took it out on the street and got 23lbs of boost and a butt load of power. Like I told the moron who ran the Dyno, Theres nothing wrong with my car.

 

[garrett]

?

Is there anyone out there that knows the different kinds of dynos and the pros and cons of them? These guys today measured my car at 177 rwhp! Took it out on the street 5 minutes later and had so much power,(and anger), that I could hard keep the car on the road.

 

[BlackMetal]

Certainly sounds like there wasn't enough load on the wheels/engine if you weren't able to build any boost. Strange.

 

[CL87]

I had this happen before to me. They did not know how to put a load on the Dyno. I was only able to get 4 psi.

 

[garrett]

exactly

It was like the car was in nuetral or park. You can rev it all you want, but no boost will be made. Oh by the way, they still took my $, bastards!

 

[1 quik6]

Probably wasn't all that easy on the engine either (free reving it to 5000rpms) did any non turbo cars seem to have problems? You'd think that everybody would have issues with no resistance.

I am planning on trying a portable dyno this summer at one of our local car shows. Now you have me kinda nerves. The one we are using is the Livernois dyno out of lower michigan. Anybody know that company? One concern I have is if they have employee turnover you never know how long "your operator" has been on the job. I noticed on their "help wanted" section they have an ad for a traveling dyno operatior. If I was still single that would really be a cool job! Not going on the road at this stage of my life though.

Sure would apprecitate any input on Livernois if anybody has any experience.

Thanks!

 

[garrett]

non turbo cars

I couldn't care less if it worked on the normally aspirated cars. I didn't stick around. I went to another section of the event where the car show judging was to be done, and met some friends.

 

[Chuck Leeper]

Fwiw....

All a chassis dyno does, is measure torque at the wheels. There is a large drum of known diameter and mass. The Dynojet, [and most other drum dynos], measure the rate of acceleration vs. time, and calculates the torque required to make that happen. It also measures RPM from the engine so that it can make the simple calculation for HP. That is made by Tq x RPM/5252.

I have had many times when the dyno input was incorrect. This was caused by the ign on a TR, being waste spark, will cause phoney rpm input.
This alone, WILL cause bad readouts...At 1 time the Dynojet rep told us to buy an electronic pickup,[option involved a timing marker and a sensor] The cost was absurd, so it was not purchased.
A case in point: My GN would not trigger the tach input.. We tried several wires, and no deal. The car was taken off, and my bud's Vette was put on... WHAMO! Good pulls. This was on a NEW Dynojet
Some designs allow for constant loading. This allows the operator to hold a load at a particular rpm. This allows the tuner to make various corrections on VE, timing, AFR, etc. The load is then changed, and more corrections are made.

I'm suspect of the rpm input they got. If the pulls were FUBAR, he should NEVER have taken your money...
Chassis dyno #'s are fun to look at, but unless you are doing tuning while making the pulls, the results are nothing more than expensive cruise nite BS material.

 

[garrett]

Rpm

This guy stuck a thin wire probe down into the #1 injector to find a RPM signal. He then had to correct it using his computer. It kept comming loose and he would lose the signal. I should have known then that he was a hack.

 

[Chuck Leeper]

Yep...

This guy stuck a thin wire probe down into the #1 injector to find a RPM signal. He then had to correct it using his computer. It kept comming loose and he would lose the signal. I should have known then that he was a hack.

A bull$hit deal all the way around.. Cept he got paid for his part.:frown:

 

[garrett]

different dyno

I'm going to go to a different guy in town who dynoed my other turbo Buick before. He seemed like he knew what he was doing. I don't know if he has a water or electric dyno but it worked.

 

[GNVYUS 1]

+1 on the ignition wire not being read properly.

-1 on the operator taking your $$ when he probably already knew he was not getting a good signal.

I went to a day long dyno tune where everyones car expect for two were waiting at least 5 minutes to get the ignition wire to read properly. The guy at least knew when it was a half ass signal and took his time to get it right.

 

[garrett]

dyno

So, is there a dyno that is more accurate for our cars?

 

[Gary Wells]

Garrett:
I don't think that you need a different type of dyno. I think that you need a reputable dyno house and a TurboBuick knowledgable dyno operator. Google will fix you up with a # of dyno houses to chose from, your cell phone will find a repuatable dyno house after talking to them and whetehr they have a TurboBuick knowledgable dyno operator. HTH. Find some turboBuicks in your area and find out where they go.