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TRA turbo arm weight

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simbatheking

Well-known member
Feb 5, 2010
232
60
28
invermere bc
Well I'm really happy that my issue is resolved. The bog/fall on its face issue was caused by not enough weight in the pins and what resulted was there was not enough heat/back pressure to spool the turbo up fast enough and fuel would dump in before it could build boost. I'm back to the 2mm oversize rollers and had to add an additional 4g on top of the 3.4 g that the bigger rollers add. I'm back to my titanium spring which Renton has confirmed is a 130/290. Today I tested it in some very heavy snow which just got rained on and with the 3" track I could pin it from a stand. Still and instantly almost flip the sled straight backwards if I didn't let off the throttle. My only concern is my shockwave is still at about a 54 or so deg angle. My primary stays cool enough I can keep my bare hand held on it but the secondary is hotter for sure. Sorry didn't have the temp gun with. Should I change the sec spring? I also love the lower engagements with the big rollers. Way better fuel mileage on trail too. I'd rather not add any more pin weight if I can avoid it
 
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turbo800

Well-known member
Lifetime Membership
Nov 27, 2007
848
214
43
Northern,UT
Sorry guys, I sold my REV turbo and been riding the Viper all year so I haven't been in here much.

My buddy has the same problem with his Etec turbo. It seems like its either bouncing off the rev limiter or its dragging the belt through the secondary and its smoking hot.

I've heard Tom's has a new set of turbo specific ramps. Maybe that will help load the motor in the right places. I've heard some guys are having good luck with ground 417's, that might be an option too.
 

Backcountrypro

Well-known member
Lifetime Membership
Nov 26, 2007
400
124
43
I ended up running Tom's arms weighing around 76 grams total. I installed DJ's Mountain ramps.....which are almost identical to the ramps stamped "035" from Tom's. A 160-290 primary spring. The secondary has the heavier XP spring and DJ's helix. I geared up from the factory 19:51 to 23:51. Clicker #1 for 10 lbs of boost and clicker #3 for 6 lbs of boost. She is perfect for me!

I hit 92 MPH on the trail with this set up.....not that I care about speed on the trail but it was fun to get it up to that speed.
 

lancelarue

Well-known member
Lifetime Membership
Nov 28, 2007
214
63
28
70
Valdez, Alaska
I realize most people don't talk total arm weight, but I didn't know how much weight difference there was between the TS arms and stock arms, that why I was asking for TOTAL weight. I measured the stock arms this morning at 60 grams. That means I'm only running 10g more than stock, but I know it needs more pin weight!

I have a brand new GTX2863 turbo for this year. It'll be interesting to see if it needs even more weight.

You're giving up some running the TRA 2 versus newer TRA. When we changed years ago, gained in the pull.
Team Tied versus the old Team is a good bang for the buck also with the correct setup.
All that $ / hp, it would be nice to get it to the snow-----------------
 
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