05 turbo vector problem need some info

[turbo99]

i put a new motor and turbo this year 2860r. the problem is at wide open and mid range it pops like back fire maybe but not that loud . i put bigger jets in 152 could it be to rich. a/f guage is reading 11.5 sometimes 10.9 jumps around a bit. would being rich cause this problem? i was told you want to be in the 11.5 range? also the performance is way down im geared to run 110mph but now i only can pull 75 or so. any ideas .. i was going to try to jet down a bit. thanks for the help i ride around 4000 and 8000 max

 

[Linc]

Check your fuel pressure.

 

[turbo99]

i was ajusting it all day today trying to get it just right but couldn't find the sweet spot. im going to hook up a guage to see what it is . what should it be?

 

[Linc]

No more than five at an idle and depending on what the boost is.

 

[sledfvr]

Mine started doing that last year and I fought with jetting for about a month before I realized that there was moisture getting in my spark plug caps. I siliconed the caps and put them back on and haven't had a problem since. My plugs were all rusty when I pulled the caps off, so it was a dead giveaway.

 

[turbo99]

boost is 15lbs.

and ill check the caps

 

[sledfvr]

What turbo kit do you have on the sled? Is it building boost to the full 15lbs, or popping so bad that it won't boost? Usually if you're rich then it will make more of a gurgle sound, and if its doing it in the midrange then it's probably your needles. Lean conditions pop, but not usually constantly, only a pop here and there and will still build boost. Hope this helps.

 

[my dog skip]

sure your not hittin the rev limiter?

 

[Linc]

So you should be around 20 + psi fuel pressure at full boost.

 

[turbo99]

What turbo kit do you have on the sled? Is it building boost to the full 15lbs, or popping so bad that it won't boost? Usually if you're rich then it will make more of a gurgle sound, and if its doing it in the midrange then it's probably your needles. Lean conditions pop, but not usually constantly, only a pop here and there and will still build boost. Hope this helps.

yes it is a gurgle sound. i have a simons cpr kit pistons and rods its poping so bad i let off before it can build boost it hits around 10-12 lbs. at 8000rpm then the poping starts. target rpm is around 8700.it started at an idle so i raised the needle 3 shims per jeff simon cpr and increase feul P by half turn . shims solved that problem now its mostly top end. poping is constant at 78 and up. if fuel pressure was to low would it run lean? if fuel was to high would it run rich?

 

[airtractor]

Give it a try

Mine started doing that last year and I fought with jetting for about a month before I realized that there was moisture getting in my spark plug caps. I siliconed the caps and put them back on and haven't had a problem since. My plugs were all rusty when I pulled the caps off, so it was a dead giveaway.

For some reason I started my rx 1 one night in the shop and noticed that my caps were sparking over to the head. So run it in the dark once. I also had a high end pop or break in power at full power. One of my other problems was exhaust leaks--you cant have any on the exhaust side--fixed that problem by going with a single piece from the engine to the turbo.

 

[SLY]

152 jets sound way big. I don't have my info here but I seem to recall running 130-135's. That was on a rear mount at 13lbs.

 

[turbo99]

145 jets are stock

 

[turbo99]

For some reason I started my rx 1 one night in the shop and noticed that my caps were sparking over to the head. So run it in the dark once. I also had a high end pop or break in power at full power. One of my other problems was exhaust leaks--you cant have any on the exhaust side--fixed that problem by going with a single piece from the engine to the turbo.

its a front mount 1 peice unit. how can you check for exhaust leaks with the turbo still on?

 

[sledfvr]

152 is pretty rich. I am at 140 with my mains and that is richer than most. Most people are around 135 and less. I don't know if its because of the big bore kit or what. When my exhaust donuts were shot it just took longer to build boost and didn't seem to pop at all. Your issue sounds like it is either too rich or a spark problem to me.

 

[sledfvr]

I have my fuel pressure set at 5 psi. I have played with that a little and it doesn't seem to make much difference. That fuel that doesn't get used just cycles back to the tank. I would put 140 jets in, needle in the middle position and try that. And make sure you don't have any moisture in the caps, I'd put a bead of silicone on them before you stick them back on and I used diox grease on the connection to the plug..

 

[turbo99]

I have my fuel pressure set at 5 psi. I have played with that a little and it doesn't seem to make much difference. That fuel that doesn't get used just cycles back to the tank. I would put 140 jets in, needle in the middle position and try that. And make sure you don't have any moisture in the caps, I'd put a bead of silicone on them before you stick them back on and I used diox grease on the connection to the plug..

thanks for the info ill get that done see what happens. ill let you know

 

[Linc]

If you're over 5 psi the gas will push past the needle and seat and under of makes it too lean, not only that but the high pressure will make a rich situation, and not enough will make it pop and back fire at full throttle, continuing the pop is bad because that's detonation which will lead to a failed rod bearing,,, don't ask me how I know. 150 mains seems too rich to me.

 

[turbo99]

it was at 4psi fuel pres. now at 5.
changed jet was 150 now 145
took all 3 shims of the needle we ll see what she does thanks for all the help
caps look good no spark on block

 

[letsgetrad]

after reading all of this it sounds like electrical. you never changed anything in your carbs when u rebuilt your motor. check and make sure your getting strong spark, maybe a electrical connection does not have a good contact. and if its running crappy at mid to high rpm and above 10lbs of boost it might be your spark plug gaps. with a new motor you could be snuffing the spark out. so tighten the gap a little. my friends apex was doing that.