Buddy just got an 07 rtx and I have an 06. His has the proaction and I have the mono. Tested sleds on a groomed test track. I'm runnning a cobra and he the ripsaw. I also have the Ulmer fuel and ignition controller and Ulmer air box mod. He has 22/38 gearing and I have 23/38. We both had same amount of fuel and weigh within 15lbs of each. Stock clutching, he is running a Yamaha belt and I'm running the xs belt. His has low windshiel and I have the midheight. His comes out about 10100 and quickly climbs to 11000. I come out at about 9800 and steadily climbed to 10900.
First test we would come out even and then in the mid I would pull about a length and then from about 80mph on I would slowly inch away. In 1/2 mile I would at best have 2 lenghts on him
Went in and did the air box mod to his, huge bog then bumped the idle mixture setting to 12. He is coming in at around 4000 and I come in at 4500rpm. After this went out same everywhere but I now pull at best 1 to 1 1/2 length in the same distance. Temps were the same -30C.
At about 80mph his sled seems somewhat loose in the back and mine solid. I would bet that if his would hook solid like mine it would be a wash even though I'm running the fuel and ignition controller. Next week will try running without the fuel contoller and ignition controller and they run his with stock weights and mine with the dragnflys. He is also running stock plugs and mine the iridium plugs.
Thus far anyone who has done all the mods and said they picked up a ton of performance???
First test we would come out even and then in the mid I would pull about a length and then from about 80mph on I would slowly inch away. In 1/2 mile I would at best have 2 lenghts on him
Went in and did the air box mod to his, huge bog then bumped the idle mixture setting to 12. He is coming in at around 4000 and I come in at 4500rpm. After this went out same everywhere but I now pull at best 1 to 1 1/2 length in the same distance. Temps were the same -30C.
At about 80mph his sled seems somewhat loose in the back and mine solid. I would bet that if his would hook solid like mine it would be a wash even though I'm running the fuel and ignition controller. Next week will try running without the fuel contoller and ignition controller and they run his with stock weights and mine with the dragnflys. He is also running stock plugs and mine the iridium plugs.
Thus far anyone who has done all the mods and said they picked up a ton of performance???
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First off, Dump that belt, because they are way to inconsistent and go back to the stock OEM.. The XS belt drops the RPM by 3-400. Unless you clutch for that belt you are losing everywhere with it.. 9800 is way to low to be coming out at. It should come in at 10,400 and roll to 10,800-11,000 on top.. You need some clutching to match up your mods.. Get Turk to match up some clutching for you..
I don't believe the stock clutching will allow you to pull that high of RPM, so you are not taking the full advantage of the ignition controller, since Ulmer raises the timing up top..
The proaction skid is better for weight transfer out of the hole than the the mono.. By a good 2-3 sled lengths... When racing make sure your transfer rod is set to max. It only takes a min.. The mono is better on top end.
Third he is beating you in the gearing. 22/38 pulls awesome to 110-114mph. Way better than 23/38. 23/38 will show it's true colours on a road or ice and that's it... I run 23/40 which is about the same as 22/38.
I don't believe the stock clutching will allow you to pull that high of RPM, so you are not taking the full advantage of the ignition controller, since Ulmer raises the timing up top..
The proaction skid is better for weight transfer out of the hole than the the mono.. By a good 2-3 sled lengths... When racing make sure your transfer rod is set to max. It only takes a min.. The mono is better on top end.
Third he is beating you in the gearing. 22/38 pulls awesome to 110-114mph. Way better than 23/38. 23/38 will show it's true colours on a road or ice and that's it... I run 23/40 which is about the same as 22/38.
apex 06 clutching is dead nutz on with that belt. On snow with no studs for drag racing his rpm,s are perfect. There has been a lot of clutching done to his sled.
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Turk said:
But Mike, should'nt he becoming out of the hole a little higher than that? Like 10,200 and pull to 10,500-10,600 with the stock clutching. I think he is giving it up there, plus match the gearing.. Like I said to the proactive rear skid has better transfer than the mono. The mono has better top end.
Is that Ulmer's old drag sled?
We tested this. This is optimum for rubber on snow.This sled has a lot of testing done to it. It was also an ulmer racing former grass drag sled.
I agree that neither sled is set up perfectly by any means....the point to this testing was to see how the air box mod worked and we did that. My skid is stock settings...anymore transfer and the skis will come up too much, track spin and bog. Were are you coming up with the xs belt being no good. I've had it 500 miles and it is wearing fine, lowered rpms 300 everywhere, thus means doesn't slip, runs cool, and I've found consistant. I'm running the 87 octane settings on the controller, does Ulmer add timing to the top with this map? What are you basing your info on, ie clutching, rpms, skids etc?????
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I also think your engagment is to high. Stock is 4000RPM. You may be blowing the track out, especially with no studs...
How did Allen set up you PcIII when you aren't running his air box mod, says that you are running Fixpowersport? What rpm are you coming it with Ulmer's clutching? Did you go straight to the cobra studded from the stock ripsaw, if so how did they compare. How did you come up with 23/40 being better on snow when not studded vs 22/38 or 23/38?
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apex06 said:
You know what bud, you can do what you want, since you seem to have all the answers... Surely seems that way in your PM's that you sent me... I was only trying to help.
Mine comes in around 4000-4200RPM. Once the sled has been running for a bit, it seems to come in at 4000.
My Ripsaw had 144 and 168 1.450 studs. My Cobra has the same stud size @ 144. Also, Allen never indicated that to me that it was on grass, since when the 07 RTX came out in the spring of 07 when he was testing the prototype on snow... I would bet 10-1 that Allen has an old map loaded in the PCIII, because I just got an updated one the other day that has almost double the timing and he said that the map I have is very old. I bought my PCIII/Ign Nov 2007...
The Fix and his air mod are about the same with the Fix being a little louder and the FIX may give 1-2mph faster on the very top end... 23/40 is the almost the same as 22/38. I ran 24/40 which is the same as 23/38 all last year. On a 1 miles hardpacked groomed SNOW trail, the 24/40 showed better than 23/40, but the 23/40 acclerated better and top out only 1mph difference in less distance. I changed the gear the same day and tried it... On ice/snow, there is a good 5-6mph difference between the gears.... You know... You are trying to see the effects of the mods, but you are not setting your sled to see the gains. You are also not comparing apples to apples here. The 07 RTX has a competely different skid. You need to compare it to another sled that has the mono to verify a specific test and at least use a test sled from before and after you did the mods....
How can you show the true performance of the mods when you are blowing it out the track... Stud it and then run it before and after.. If you really want to see some mods go in snow, then run NOS, Turbo or SC. Then you will see the difference from stock. Theirs one thing I learned about the Apex is this... You need traction to show it's true potential in accleration. Sure you may some better top end without studs, but you will need the distance to show it...
I'm done wit this post, since you seem to think I'm a F*&^^%$% idiot...
"Have all the answers".....Unless I getting it wrong, my last post was all questions. I listed what I found on snow, 2 different sleds, starting to try different mods, that's it, nothing less, nothing more. My xs belt comes in at the same rpm everytime, hot or cold. And yes, same as yours my engagement lowered as I did runs, my guess would be that the yamaha belt when I was running one was getting warmer, more sticky, thus lower engagement, or one could say inconsistant performance.
**APEXGT**
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I didn't like the XS belt... I went faster with stock belt
What didn't you like about it? What is you toughts as to why the stock Yamaha belt is faster? Did you find that it gave and inconsistant shift?
SledFreak said:
This is more true than anything I have read on this topic. Well said and spot on.
Forgot to mention guys, please keep this discussion positive and constructive. Doesnt do anyone any good to argue over it.
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