Well, which dyno.to use. I honestly dont know? Which one would be the best one to use?

Unfortunately for me, where i live, no chassis dyno available. My truck: 99 F250LD
SC 4X4 A.T. 4.6L 3.73 axle ration. GVWR: 7200# Certified scale, truck currently weighs 6100# (shortbed with snug-top & lots of stuff loaded in bed).

No more 250LD--now there F150 HD, as i understand it.

I read almost all the posts before i decided to purchase the "Superchip-flip chip"(from Mike T.) 87/92oct. Only other mods. cat-back & K&N filter. One thing i can do pretty well is reason through and thats what i did. However it sure wasnt easy, because this site is loaded with really good pros. & cons. Big strappers like "Neal" & others to "little strappers" ( me to) & lots of tech. advise,comments.

Now my point is: I did get chip, but really wanted to do pulls on dyno first, that didnt happen. Does the chip work "yes" How do i know, well because i can feel the increased performance & trans. shifts. However--

I want to do dyno. pulls. Yeah i know, it adds up but i really want to know what the chip is putting out. I dont recall seeing any current dyno. graphs showing pulls for hp, torque curves etc. on this site.

When i get clear on what dyno. i need to use, ill do it. If i can figure out how to post results, ill do it. This is strictly for my own benefit, but will pass along.

Going to Las Vegas in May. Maybe ill find a dyno. that can do my truck?

So WHAT DYNO. DO I USE? This is a good site, keep it up. Didnt think at my age i'd get involved in this new hi-tech stuff but i did, keeps mind young, it really does.

Thanks to those that feel they can reply to this old timer!

 

Hi Old Timer,

You'll get the most accurate results by using an "eddy-current" chassis dyno, though there aren't nearly as many of those in use, due to their expense, as there are the "inertia" types of dynos like the Dynojet.

So if you can find a modern eddy-current chassis dyno, that is your best bet.

Usually what most places will have available is a Dynojet, as they are affordable enough so that just about any shop owner can lease one and do well with it financially.

One thing to realize is that with an automatic transmission vehicle, it's very hard to get good stabilized readings, as they'll have to take it up in 3rd gear to the point at which when they punch it, it will no longer downshift back into 2nd gear, so most dyno plots won't even start until well over 3000 rpm, which doesn't give a dyno enough time to fully stabilize in many cases, for good accurate readings. (the background on this is that dyno pulls should be made in 1:1 gearing, so for most automatics this means 3rd gear only, and for most 5-speed manuals, 4th gear only, to avoid the skew caused by the torque multiplication of being in a lower gear)

There are so many variables, from the type of dyno to the operators knowledge & skill, to what you have to do to isolate the program changes in the ECU, etc. that it takes a good eddy-current chassis dyno & strict procedures to get any real accuracy.

If you'd like to give us a call, we can go over some of that with you, to give you an idea of what you'll need to do, and what you'll want to ask various shop owners, etc.

For most people, they just say to heck with all that, and just live with what numbers they get from their local Dynojet.

------------------
Mike Troyer
Performance Products, Inc.
National Distributor of Superchips
(540) 862-9515
Email: mtroyer@compuserve.com
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