sledracer
Extreme
03 RX1 with Bender stage II - has a Prologger Boost on it now.
Ive been fighting issues thru the asphalt season. Carbs have been gone thru and seem ok. This weekend was a bit different after a small change. The Bender stage 2 has a toggle switch for boost settings. On the low setting it should run around 6lbs on the high setting it should see 10. On the low setting boost seemed to jump around a bit and would never reach 6 lbs.....around 4.5lbs. On the 10lb setting it seemed to be quite a bit more steady at 10lbs.
I put on the Prologger and it still seemed to behave similarily. Before this past weekends race I had the seat off and tightened the waste gate actuator rod 1/2 turn just to see how it would react. Boost and RPM now seem to surge quite erratically. On a wide open 1/4 mile pass it surges ever....dunno couple seconds. Boost goes from 4.5lbs up to 7lbs. RPMs go up and down from 9400 -10100 rpm. I surges hard enough it actually moves my head up and down a bit.
Any thoughts on what might cause this?
Thanx Tyler
Ive been fighting issues thru the asphalt season. Carbs have been gone thru and seem ok. This weekend was a bit different after a small change. The Bender stage 2 has a toggle switch for boost settings. On the low setting it should run around 6lbs on the high setting it should see 10. On the low setting boost seemed to jump around a bit and would never reach 6 lbs.....around 4.5lbs. On the 10lb setting it seemed to be quite a bit more steady at 10lbs.
I put on the Prologger and it still seemed to behave similarily. Before this past weekends race I had the seat off and tightened the waste gate actuator rod 1/2 turn just to see how it would react. Boost and RPM now seem to surge quite erratically. On a wide open 1/4 mile pass it surges ever....dunno couple seconds. Boost goes from 4.5lbs up to 7lbs. RPMs go up and down from 9400 -10100 rpm. I surges hard enough it actually moves my head up and down a bit.
Any thoughts on what might cause this?
Thanx Tyler
mbarryracing
TY 4 Stroke God
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- 2006 Yamaha Attak Turbo
2015 SR Viper RTX-DX
1996 Vmax 600XT
What is the AFR doing when the surging is occuring?
I couldn't remember what you posted before, but do you have any exhaust leaks before the turbo? (clamps, donuts, etc)
I couldn't remember what you posted before, but do you have any exhaust leaks before the turbo? (clamps, donuts, etc)
HURRICANE
TY 4 Stroke God
check your system for boost leaks.
I would agree. I had an issue with leaks in my carbs until i got the billet carb-caps.
On ice 1 or 2 runs, after that things warmed up and started leaking. When I went to the tar all was good and tight with the new caps.
--Buster696--
On ice 1 or 2 runs, after that things warmed up and started leaking. When I went to the tar all was good and tight with the new caps.
--Buster696--
sledracer
Extreme
Ive got billet caps and T's now. Ive checked their sync as well. I will pressurize they system and check for leaks on the exhaust/turbo end.
HURRICANE
TY 4 Stroke God
pay close attention to the charge tube under the tunnel
sledracer
Extreme
What does one look for on the charge tube? cracks? This one looked good during install, its never seen snow since and only a handful of tar races this summer.
thanx Tyler
thanx Tyler
thinksnow
Expert
The charge tube in the tunnel is probably where you have leaks. I TRIED to pressure mine up a couple years ago and it wouldn't build any pressure at all. I pulled the tube and it was FULL of cracks where it mounted. I had it welded up and the problems went away.
tube
I blew my charge tube open no bov, the next year my exhast champs were loose sled would not build proper boost, jeff
I blew my charge tube open no bov, the next year my exhast champs were loose sled would not build proper boost, jeff
sledracer
Extreme
Hooked the shop vac up this weekend. Was a slight leak where exaust pipe hooks into the turbo inlet pipe. Nothing major BUT there was a big leak where the turbo flange bolts to the 1/8" stainless frame/exaust tube connection. It was warped or bent a FAT 1/16" I'd bet and the gasket wasnt close to think enough to make up the difference. Not sure if it was heat warped or if my lill crash on the driveway last summer contributed.
Glad I happened to check the flange cause I just happened to be in the neighbourhood.
Glad I happened to check the flange cause I just happened to be in the neighbourhood.
sledracer
Extreme
I build a new flange for the turbo mount. Had the sled out to the track this past weekend for the last race of the season. First pass the sled ran 10.23 at 131 mph. I forgot to record the run with the Prologger and didnt watch it close enough although I thought Id seen 8lbs boost. Was concerned a bit so I threw some C12 in the tank for a bit more safety. The second run I saw get messed up at staging and didnt record again but say 12lbs this time. But not sure what it was doing the whole run. Ran 9.98 at 133mph. Pulled the seat and found the actuator hose had a big split in it and the waste gate was probably totally closed. Fixed that and the sled ran 10.8s the rest of the day.....were I thought it should be from day one. Sled started surging again which likely has to do with the Prologger boost controller settings.
Thanx for all the advise; was good to know that the sled could run the numbers I expected it could.
Thanx for all the advise; was good to know that the sled could run the numbers I expected it could.
