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Discussion Starter #143
Not a lot been going on this winter. Took it to an uphill 300ft snow drags in february and lost to a PSI 1500cc triple in the first round.
Other than that I replaced the primary clutch which had cracked the outer sheave.
After consulting with friends who run a record holding Yamaha drag sled, I then went on to install 8T anti ratchet drive sprockets and shortened the skid to make them fit. Haven't had a chance to ride it since but I had a big problem with track ratcheting before, had to tension the track tight as a vee belt to keep it from slipping. The anti ratchet sprockets should allow me to run less track tension and thus have less drag.




I also picked up some tunable flyweights from STM to facilitate finer tuning of the clutching.
 

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Discussion Starter #144 (Edited)
A lot going on in the summer. Cracked the second P85 clutch testing on sand, switched to a HRP billet quad cam. What a difference, the HRP gives me 7000RPM engagement without needing 200lbs spring pressure. This means the shift curve is more consistent and I get better back shifting than with the Polaris clutch.
I went to the sand drags and claimed first place against an 800cc mountain cat 141 in the finals. Ran an easy 4.86 at 106km/h, very soft start, ran without launch control because I hadn't adjusted it for the high engagement speed.
Sled handles okay, mostly goes straight after I tilted the skid at the front. It's difficult to steer when the direction needs adjustment though.
Now I'm going to get my hands on a bigger track to take advantage of all the space created by the smaller drive sprockets and maybe get rail extensions to 144" for the snow drags in january. I've also maxed out the Lancer Evolution injectors, might put in a set of 750cc I have on the shelf.




 

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That's a loaded question..

Yes there is, but not with publicly available software definitions. There's at least 2 people besides myself that have done it.

I was going to make and sell kits, but there wasn't enough interest for me to spend the several thousand cash that would be required for prototyping and assembling the first kits and creating software.
 

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id really like to learn how to do that I work at a car dealership so ill understand what you talking about I just don't know how your hacking the ecu to takecontroll of it and have a data log. If you can do it to one ecu you should be able to do it to any ecu if you have the know how right ? I asked jj and he told me to alk to you I know you've probably been asked this a million times.
 

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The taking control of the ECU you speak of, does not work on these, as they are not reprogrammable as they are.

All the code and maps are stored on a prom chip inside the ECU. It has a few bytes of static ram so it can store error codes, but not enough to run code in and make changes to the mapping or operation..

What you need to do is pull the chip from the ECU, dump it, analyze it, find the code or maps that you want to edit, make the changes, and burn them to another chip or put them into something else to take the place of the chip, and put it back in the machine.

I got as far as being able to put a replacement chip into the ECU and re-program it through the select monitor port, but as I said several thousand more $$ is needed to complete the project, make it reliable, and idiot-proof. I also have the hardware here to make it programmable through bluetooth so it can be done from a phone, but that will take development of yet another app. There's just not enough interest in doing this to 20 year old sleds, and I already have over 1,000 hours invested, and I can't count the dollars..
 

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ok from that there I will work with my buddy that is good with computer I will try to make another program and apply to other apps thanks I know this will take a while to figure out what type lang are u using to write software?
 

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I used VB in a shell for the alpha stuff to reprogram the chip in place. Something in c++ would be best used for coding something for heavy duty use, as the VB and shell doesn't have very good GUI.

The code on the chip is particular to the CPU running the ECU.
 
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