Turbo runs like Sh*t!

03HAYABOOSTA

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I have the velocity stage one kit with a full built motor. i had the bike mapped at a great shop who really only works on turbo bikes. the bike is VERY hard to start after it sits over night. second it runs real rough below 3500rpm's at around 0%-10%throttle (cruising range)...it pops, sputters and breaks up. when i kill it and boost up it runs strong! ive had the bike mapped over and over and this prob never seems to go away. i sync'd the throttle bodies, checked the throttle posistion sensor, and cleaned the injectors out. i really have no other idea what to try or what could be causing this. anyone have any ideas??!!
 
Shoot me your email addy. I have a MAP that you can try out. You may have to punch in the numbers manually, but it may help. I had the same problem with my setup. I started with the numbers on this MAP and tweaked them a little to work with my setup. It's at least a decent baseline to start with.
 
fuel pressure is 42psi at idle(1100rpm) ive checked and triple checked all the vac lines. this is driving me nuts
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As a favor to you to keep your sanity, Simply Send me your Bike. I'll transfer the title into my name and ride it for a long long long time and write you a very nice thank you note once a month. Problem solved!
 
Yea it rises just like it should. as soon as i spool up the pressure goes up.....but it runs great under boost thats not the problem. its runs bad before boost.
 
I have a completely different setup than you but I'm guessing it is the infamous 8% range. I ended up with anywhere from -10 to -30s in my 5-10% throttle range from about 2-5000 rpm. I used a LM-1 + LMA-3 to data log and rode around and made changes for half a day till it no longer surged. I would be interested to see a copy of your map if you wouldn't mind sending it.
 
Yea ill send you the map the guy put in the bike for me. if i remember right i think in the area of the map your talking about he has +5 to +20. you can private message me you email and ill send away. by the way i watched you video...good to see that you used your blinkers while doing 140 on a turbo busa
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Sent you a copy of the MAP I was telling you about. It will definitely be night and day difference from what you have. Especially if you have +5's & +20's in that area. Good luck. Let me know how it does for you. Just remember to save the MAP into your Powercommander folder so it will recognize it.
 
i have seen and heard f this a few times. I think you will find that there are a few connections in the wrong place. Specifically ask Velocity or lok for a shop that has installed the kit, not just they installed and tunned Turbos.
 
iap sensor. see if the vac line is hooked up yet. it needs to see vac and will create low rpm driving issues. it can be damaged pretty easily by boost if boost isn't vented off that line.
 
I didnt recieve the map. ive been looking everyday afterwork for it. a guy a few messages above asked about my cams and timing. the cams are stock and i have no idea what the timings like. i had the motor built at a shop in long island known for fast a$$ turbo bikes. i have no idea what the timimgs set at, he has his own degree wheel he uses. im thinking maybe i have a bent throttle body butterfly, anyone have any ideas how to check for that??
 
Oh and to answer another question above, all the vaccuum lines are DEF installed right. i checked and double checked. plus the shop that built the bike installed everything after they built my motor. im not a fan of velocty's tech support, i think they all took the short yellow bus to school when they were younger. i could ask 2 or 3 guys the same specific question, and get 3 different answers. ive even spoken to Barry Henson from velocity. didnt help that they sent me the wrong dump pipe from the get go either....sent me a pipe for an external wastegate but im running the stage 1 kit which has an internal gate so the pipe wouldnt let the wastegate open. id never reccomend velocity to anyone. wish i woulda bought an RCC or Hahn kit
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A bent throttle blade should have showed up during balancing and a bent blade should be able to be seen.
Pretty hard to solve problems like this over the internet but these are the obvious things to check. Some of these you have heard before but stated slightly differantly so double check before discarding the possibility out of hand. I'm going to assume that you try another fuel map first.

1) Vacumn leak.
Check all lines that connect under the throttle blades for possible leaks. Carb cleaner sprayed around the area while idling the engine may be helpful.
Check that one or more throttle bodies haven't been pushed out of the rubber boots.

2) IAP sensor
This sensor must be connected to all four throttle bodies and those lines must not be connected to anything else that vents to atmosphere.
Try swapping the sensor with someone elses. They do go bad and are expensive so I would buy one unless it is proven to be bad. As someone stated previously the IAP sensor and rpm control low load (0-10% throttle). Above 10% fueling is controlled by throttle position and rpm.

3) Power Commander
These can also go bad. Again try a swap if possible.

4) Fuel return line
A kink in the return hose or too small of hole in fittings could cause an over rich condition at low rpm.

5) Cylinder balance test
With the idle set high enough to keep the engine running disconnect one injector electrical connector at a time to see if all cylinders cause the same rpm drop. If its a single cylider causing the problem it would have less drop.

If none of these are found to be the cause I would put it on a dyno with a wide band sensor, run it at constant throttle in the range causing problems and see what the A/F is doing. That may give you new direction.
 
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