Lets talk cluching on the turbo pro
- Thread starter allblowdup
- Start date
I haven't tried mine yet, but I'm gonna go with 75g weighted a tad bit heavier on the tip as well. Planning to run 6 - 9# at 6000 to 8000 elev.
T
TurboMatt
Well-known member
Has anyone tried gearing DOWN a turbo pro, or any turbo sled for that matter?
Would this bring back some of my bottom end? Would this allow me to run less weight in the primary(like ti does on n/a) sleds, thus helping the bottom end? Obviously, you'd loose some top speed but for a boonedocking specific machine like many of these turbo pros are, this may not matter.?
Would this bring back some of my bottom end? Would this allow me to run less weight in the primary(like ti does on n/a) sleds, thus helping the bottom end? Obviously, you'd loose some top speed but for a boonedocking specific machine like many of these turbo pros are, this may not matter.?
Todays test...weather clear, 7000', 18"of powder,solid base.
Clutching as follows
primary
76 gram rooster, all weight in the TOE...using the tungsten washers
Team orange spring 165-315 (maybe need a lesser finish pressure tho)
secondary
helix 40-50 .40
spring 145 300
boost 10 psi, max rpm 8150
this is getting very close, pretty good bottom end, and when boost comes on the 50/300lb holds it very well. Engages at about 4200
but i'll live with that.
the 40 with lighter primary weight helps the bottom end a lot.
I would probably go with a 40 48 .4 for lower boost, the 50 300lb loads the motor really hard, 6psi pulled 7700.
couple more combos to test, but the 40 50 .4 is a good helix, you just MUST run a VERY high finish pressure spring or you will blow through the secondary.
Clutching as follows
primary
76 gram rooster, all weight in the TOE...using the tungsten washers
Team orange spring 165-315 (maybe need a lesser finish pressure tho)
secondary
helix 40-50 .40
spring 145 300
boost 10 psi, max rpm 8150
this is getting very close, pretty good bottom end, and when boost comes on the 50/300lb holds it very well. Engages at about 4200
but i'll live with that.the 40 with lighter primary weight helps the bottom end a lot.
I would probably go with a 40 48 .4 for lower boost, the 50 300lb loads the motor really hard, 6psi pulled 7700.
couple more combos to test, but the 40 50 .4 is a good helix, you just MUST run a VERY high finish pressure spring or you will blow through the secondary.
Guy I ride with a turbo geared his down one tooth on the top to 19. Got to try mine for the first time this weekend. Ran 6500 - 7000 ft elevation with 100LL at 10 lbs worked really well. Hit the det few times going up the trail and noticed it's caused more when playing with the throttle too much. Other then that sled ran flawless. Clutching was bang on at 75 g
for me running more weight on the tip with the sled hitting 8200-8400 rpm.
for me running more weight on the tip with the sled hitting 8200-8400 rpm.
T
TurboMatt
Well-known member
Have you done any more testing on this 2XM3?
I was able to get my sled out on the snow again this week WITH the turbo. It ran really well. I was running about 8psi(sometimes hard to say with Silber junk boost gauge) on straight 100LL, was riding in West Yellowstone, usually 7500'.Never hit the DET, lol. I have my sled geared down now, running 19/43, I was just running the springs and Helix that Silber sends with the kit, 76grams in the weights all in the toe. I thought it ran very good, the bottom end seemed pretty and I didn't think there was any negatives to having it geared down.
I do have one question though: I changed my belt Friday night after riding(I noticed a cord starting to pull). The next day(Sat.) we rode some really wet heavy deep fresh snow. My rpm dropped from running around 8100 the previous few days to running around 7500-7600rpm that last day. Did this happen because of the belt change(ie this belt was wore out) or was it just the wet heavy snow doing this? The belt I put on was somewhat unknown. It was the spare that came with the sled, it had use, but seemed ok. I do plan on getting a couple new belts but just wondering I guess
I was able to get my sled out on the snow again this week WITH the turbo. It ran really well. I was running about 8psi(sometimes hard to say with Silber junk boost gauge) on straight 100LL, was riding in West Yellowstone, usually 7500'.Never hit the DET, lol. I have my sled geared down now, running 19/43, I was just running the springs and Helix that Silber sends with the kit, 76grams in the weights all in the toe. I thought it ran very good, the bottom end seemed pretty and I didn't think there was any negatives to having it geared down.
I do have one question though: I changed my belt Friday night after riding(I noticed a cord starting to pull). The next day(Sat.) we rode some really wet heavy deep fresh snow. My rpm dropped from running around 8100 the previous few days to running around 7500-7600rpm that last day. Did this happen because of the belt change(ie this belt was wore out) or was it just the wet heavy snow doing this? The belt I put on was somewhat unknown. It was the spare that came with the sled, it had use, but seemed ok. I do plan on getting a couple new belts but just wondering I guess
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Well rode all day today...fun times !! my final clutch package for the pro at 10 psi is as follows;
40/50 .40 helix with team titanium spring 140/300 pound+2 delrins
gear stock, boost 10 psi
primary, 72 gr in the tip of the rooster weight
spring is Speedwerx 155/300 h5 spring
max rpm at 7200 ft is 8150.
Belts looks great with no heat checking,or other issues.
Going to try team tied next and see how that works.
40/50 .40 helix with team titanium spring 140/300 pound+2 delrins
gear stock, boost 10 psi
primary, 72 gr in the tip of the rooster weight
spring is Speedwerx 155/300 h5 spring
max rpm at 7200 ft is 8150.
Belts looks great with no heat checking,or other issues.
Going to try team tied next and see how that works.
Decided to pull my secondary and noticed the bolt was making contact to the bulk head, possible cause to the Det notched it out some more.
A couple of us here in the sw have geared our turbos down. I went to 19/42 in my td8. A buddy runs 19/43 in a td7. I know a couple others as well who went to similar ratios. It did bring back a lot of bottom end. That coupled with an Epi gold spring makes the bottom hit pretty hard. My buddy runs that spring in his silber turbo and that thing rips. I just figure at no time am I ever going more than 70 mph , maybe on a trail strait but that's not what we ride. A majority of the time our tracks maybe turning high speeds but physically we are going maybe 30 mph. Boondocking on and off throttle I like how the lower gearing and higher primary make for more linear snap across the board. It spools the turbo up so you are always in the power. I am by no means some clutch genius but I have seen positive results with this kind of set up on multiple turbos here in swco.
Pro 800 163 with 2012 silber kit but converted my fuel control box to the 2013update. It has unreal throttle response now. I also added the boondocker EBC to my kit. Like the features the EBC adds to Silbers system.
My current setup is as follows
5 psi boost on EBC
Gearing 19/42 (helped low end throttle response)
Primary team pink spring
team rooster weights 70 grams spread between heel and middle of weight pulling 8250 rpm
Walh Bro primary sheave adjuster with 2 shims on spider and 0.015 clearance
Secondary Black/Orange spring
Silbers 44/48 helix
Belt deflection is just a bump off belt squealing
My riding style is boondocking and this setup is working extremly well for me at the moment. Low end throttle response and backshift is great. Power seems to be very responsive every time I chop the fun flipper.The snow out west is not very heavy yet so we'll see how it work later on in the season.
My current setup is as follows
5 psi boost on EBC
Gearing 19/42 (helped low end throttle response)
Primary team pink spring
team rooster weights 70 grams spread between heel and middle of weight pulling 8250 rpm
Walh Bro primary sheave adjuster with 2 shims on spider and 0.015 clearance
Secondary Black/Orange spring
Silbers 44/48 helix
Belt deflection is just a bump off belt squealing
My riding style is boondocking and this setup is working extremly well for me at the moment. Low end throttle response and backshift is great. Power seems to be very responsive every time I chop the fun flipper.The snow out west is not very heavy yet so we'll see how it work later on in the season.
