the L's FIRST dyno and my thoughts--a BIG waste of $$$$
 

This was the L’s first dyno with mods of:
Cobra T/B
SuperChip R9
Johnny L’s Ram Kit II

I was getting a base line to test a couple Magnaflow exhaust systems.

What I discovered was that getting the L’s dyno using a DynoJet is a big waste of money, period. It was obvious that the numbers are skewed. Afterwards, I did some calling around to discover that the DynoJet will be kind-of OK with light vehicles like a Mustang or an Escort (even those numbers will not be accurate) BUT when a heavier vehicle is on the rollers like our L’s, the DynoJet will not only read the info. incorrectly but will be skewed so badly making any info. useless.

This means that this type of dyno can’t be used for mod testing. Because of the small increase of torque or horse power a mod will produce, the DynoJet cannot read it. It will be wrong even if one was to use the same dyno after installing the new mod only a couple minutes after the base-line run.

How the dyno was done: The L was put on the rollers, the engine was warm--not hot, the tester ran the L up slowly until it went into 3rd gear---then he went to WOT, then backed off once again to idle. Ran the L up again and went through the same process 3 times with out turn the engine off to cool down. Therefore, all the numbers should have been very close to being the same, maybe a small variance but it wouldn’t be a great variance. There wasn’t any spikes on the charts that would have corrupted any numbers.

Dyno numbers
1=first pull: rwhp 382.3---torque 520.0
2=second pull: rwhp 368.8---torque 490.3
3=third pull: rwhp 348.9---torque 473.7

As you can see, there is a big difference in the numbers when there should not be.

The company that did the dyno does know what they are doing (I check around) except that it is the dyno itself that is incapable of giving accurate numbers for the L's. As you can see by the numbers above, there would be no way to really check to see if a certain mod increased performance or not because of the vast difference in numbers from the three pulls that should have been close to each other. If I were to dyno an added mod that was to possibly generate 10 HP, there would be no way that I would know for sure whether the increase was really there because of the inaccuracy of that type of dyno.

Just my .02

Jim Shaw

[This message has been edited by FORDSALES (edited 11-07-2000).]

Jim,

Looks like some before and after quarter mile numbers at the track are warranted to get a good feel if the exhaust helps performance.

Rob

hmmm...jay at Superchips confers...he told me from the outset that dynojet dynos were a piece of ****...

------------------
jim@bulldogneon.com
smokin'




[This message has been edited by BulldogSVT (edited 11-07-2000).]

FORDSALES
There is a shop that has a very acurate
dyno and he is a big ford tuner.He is the
son of the late Les Ritchey.His name is
Randy Ritchey and his shop is called
Performance Assoc. They are in San Dimas
Phone (909)592-4441 He said call and he would
run a base line so you know acuratly what
each modification ads. Mofo

Sorry to hear about your poor experience.

I bought a Road Dyno Kit this summer to test my mods and avoid paying high costs of the dynojet places. I have had good results from it after the initial learning phase of how to use it properly.

Run after run, the numbers are pretty consistent and you can do it on your own time and for every single mod you do.

Here is a link: http://www.charm.net/~mchaney/roaddyno/index.html

the unit takes most all variables into consideration including vehicle weight, temperatures and humidity, elevation, etc.

Hope this helps some.

alessandro

SilVer Tour,
Did you hook this to a Lightning? Those Road Dyno's use an inductive spark plug wire to read the RPM, and we don't have spark plug wires.

------------------
Mark
'00 Lightning
'79+ Corvette

Sorry, but that is not true.
I've dynoed on 2 dynojets and 1 eddy current. The numbers were so close (with in 2 hp).
A dynojet (without eddy current option) is not great for tuning, because you can't load the wheels like a eddy current, so you can have a vehicle that will ping when driven on the road.

For what you did the numbers look right.
You are heat soaking the engine, supercharger, intake track, and the intercooler fluid.
You should lose a sizeable chunk of horsepower each time.
You need to monitor intercooler and coolant temps, and repeat them.

Weird message board problems...

[This message has been edited by SilverBullet (edited 11-08-2000).]

Jim I used Swanson's dynojet and the numbers were very consistent, even minor tweaks with the chip showed expected differences in horsepower. The only thing Danny pointed out was that the dyno doesn't take into account the extra load on the wheels and you could be running okay on the dyno but too lean on the street.

I've also heard of Randy Ritchey and was told to go to him (by local Ford dealer) if I want ANYTHING done right for my Lightning. Ironically I was referred to him when searching for someone to install an exhaust system.

Keep us updated on what you decide to do.

Weird message board problems...

[This message has been edited by SilverBullet (edited 11-08-2000).]

Jim I used Swanson's dynojet and the numbers were very consistent, even minor tweaks with the chip showed expected differences in horsepower. The only thing Danny pointed out was that the dyno doesn't take into account the extra load on the wheels and you could be running okay on the dyno but too lean on the street.

I've also heard of Randy Ritchey and was told to go to him (by local Ford dealer) if I want ANYTHING done right for my Lightning. Ironically I was referred to him when searching for someone to install an exhaust system.

Keep us updated on what you decide to do.

Weird message board problems...

[This message has been edited by SilverBullet (edited 11-08-2000).]

Weird message board problems...

[This message has been edited by SilverBullet (edited 11-08-2000).]

[This message has been edited by SilverBullet (edited 11-08-2000).]