PAR 910 Tuning/Sharing
- Thread starter 800xtreme
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Only thing I could get from the article on pipe temps and what cause lean and rich mids in header length. He said his theory was when the pipe was cold and he had a lean spot the header pipe was to long (they cut 1/2" off) then when the header was to shorts they had a rich spot in the midrange. I think the twin CPI pipes are really close. Like I said we are able to keep a pretty even number from 0 to 5500 rpms and them we start defueling. So the header must be about perfect. I never made it this far with tuning the single pipe so I can't really tell you what is happening with your pipe temps. If you want to send a log or two I will help out as much as I can. Try and send some with different pipe temps from cruising to hard pulls where your pipe temps peak.
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I guess I read a little more into it, what I got was it didn't matter what he physically did to the length of the pipe, the pipe temperature was always changing and there for the theoretical tuned length was always changing. Shortening the pipe worked to cure his lean problem in the mid range because the EFI tune was done on a dyno hot pipe, not a real world temperature pipe. The problem it created by shortening the pipe was if he got the pipe hot enough it would go rich in the mid range. I think his point in the end was to monitor the pipe temperature and adjust the map accordingly. It really seamed to only be about when the powerband starts. Personally I am not so certain adding fuel is keeping the pipe any cooler at the top end, it may just be making it extremely rich.
If you watch your afr each time you make a pass up a hill on a hard pull it just gets richer, so with the egt trim we are taking fuel out of the mid and top end to compensate for the sled running richer. It's better it run richer than lean.l though. It's one of those trims though you want to take slow increments out at a time. I don't think it's to keep the pipe cooler, but to have the motor run consistently from 100 degrees to 560 degrees. If you don't have a egt trim at 300 you take away +\- 10 points and and 560 degrees you only need to take away +/- 3.5 points. And at those two point it's still the exact same afr at WOT.
I am not sure how the single pipes runs compared to the twins but I would think the idea is the same
I am not sure how the single pipes runs compared to the twins but I would think the idea is the same
Rsp we need to go trough your logs. Something else is wrong. I think you are having a clutching issue. What temps are your clutches? Also another guys mapping will not work. Because you are tunning for the ultimate performance. In that case your sleds mapp will be to different then the next guys. Riding style, weight,sled calibrations effect an ultimate tune. Let's just go through it. 
The EGT trim map I saw from Bryce, added fuel as the temperature rose above 580, and took fuel away below 540 or so, I realize I still have clutching issues and I need to get some logs of my issues, I was mostly trying to open a discussion of my interpretation of the dyno tech articles regarding pipe temp and EFI tunning, anyway I believe your egt trim map must be majorly different then mine, maybe yours makes more sence to the article.
Rsp111-
I tried a different helix today just to see what would happen- it made a huge difference how the motor was loaded and how it shifted out. I went from a 73-59.46 to a 68-58.46.
My bottom and mid range were way sluggish and super rich. I wasn't loading the motor near hard enough. I put some more weight in the mid and bottom of my weights and helped a little but not much.
I agree with Bryce completely when he said someone else map or tune won't work you someone else. Especially if you are trying for the best tune for you. If you are wanting the sled setup for you. I would figure out how how you want your sled to run. If you want a lot of top end track speed, for the motor to have a lot of initial trackspeed, more short burst or how ever and then get it clutched for that as best you can and then work on the tune. If I sold my sled and the guy bought it and did nothing but drag race across lakes or straight up long long pulls. He probably would be very unhappy with how I have it setup and tuned. But if he wanted instant throttle response and a lot of low end tourque and not really worried about top end speed then, then I daring to say he would ride a round with perma grin. I love how my sled is set up, it's set up and tuned for my riding style.
My sled ran completely different just by changing the helix. I could see very easily how what ever map you have is not working as good as the same map another guy has in a different setup. I would recommend , if you haven't already, getting with Bryce and having him go through some of your logs. The MAN really knows what he is doing.
Best of luck, and be patient!! The motor runs amazing when it's setup for you!
I tried a different helix today just to see what would happen- it made a huge difference how the motor was loaded and how it shifted out. I went from a 73-59.46 to a 68-58.46.
My bottom and mid range were way sluggish and super rich. I wasn't loading the motor near hard enough. I put some more weight in the mid and bottom of my weights and helped a little but not much.
I agree with Bryce completely when he said someone else map or tune won't work you someone else. Especially if you are trying for the best tune for you. If you are wanting the sled setup for you. I would figure out how how you want your sled to run. If you want a lot of top end track speed, for the motor to have a lot of initial trackspeed, more short burst or how ever and then get it clutched for that as best you can and then work on the tune. If I sold my sled and the guy bought it and did nothing but drag race across lakes or straight up long long pulls. He probably would be very unhappy with how I have it setup and tuned. But if he wanted instant throttle response and a lot of low end tourque and not really worried about top end speed then, then I daring to say he would ride a round with perma grin. I love how my sled is set up, it's set up and tuned for my riding style.
My sled ran completely different just by changing the helix. I could see very easily how what ever map you have is not working as good as the same map another guy has in a different setup. I would recommend , if you haven't already, getting with Bryce and having him go through some of your logs. The MAN really knows what he is doing.
Best of luck, and be patient!! The motor runs amazing when it's setup for you!
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