Lean boost

[Need for Speed 2]

After 3 yeara of turbo yamaha sleds I have finally built one that hasfuel and afs where they should be, battled leaness for ever it seems with front mount stuff. Guys we spend lots of cash on this stuff but we are missing a key peice to the fuel injected sled. Injectors buy bigger injectors run the RB3 and life is great no more lean afs. I always felt my sleds were very quick but not fast. Fast means fuel and lots of it on the top end. It is amazing how much harder they pull when afs are in the 11.2- 11.4 range and I know most will feel this is rich but here at sea level on the east coast I can smell the ocean and its moist air fuel is king then comes power, for guys battling this problem at low elevation invest in injectors and an RB3 and you will be glad you spent the cash for that last peice of a perfect puzzle. Ole one eye is being pounded on the lake with 20lbs of boost with meth injection everything stock in the motor except a shim and degreed cam timing not a guess timing. I know it will be said sooner or later it will break but I am leak testing it weekly and so far 2 cyls are at 2perc and 2 are at 3 percent, fuel guys that is the answer dont be looking for the perfect 11.8 or 12.5 number put it in and she will go, also one other note I have ran a mix of 50/50 c-14 and pump gas up to 20lbs of boost 88grams of weight in a 4 arm clutch , it pulls my target rpm of 10800 then same instant I will flick the swith on my meth no changes at all, same fuel do the same pass measured on the lake and she will go up and just nick the rev limiter? Why? meth is a catalyst makes fuel burning more complete more cylinder pressure and very responsive, with the best part being cooloing internal components like valves, and header and turbo , these are my tips to date, Thanks Dave Marshall aka Hurricane this meth thing with big injectors is just perfect and Powder Dave for the RB3 I have finally got an apex that will run with anything in trail form 131 on the gun in snow cant wait to see what happens now this weekend hard ice with a tiny little crust, To everyone reading have a safe weekend ride.

 

[03turbo]

dude, i cant see the pics of this thing??

 

[mulot30th]

I do run a standa alone efi on my 136" rx1 blower at 20 psi, and it definitely feels happy when running 11.5-1...

But... being a SDS-EFI system I have a knob so I can easily adjust afr on the fly. and it definitely get about 400-500 rpm more instantly when I lean it to 12.5-12.7 -1 afr.

On the other side, power comes down VERY QUICKLY once you get under 10.5-1 afr.

That is my experience.

 

[mulot30th]

On side note, timing has a rather extreme effect on power output as well on higher boost levels.

I tried a quick 3 deg less retard at 20 psi and holy #*$&@... 500rpm gain right there.

But I set it back right after the run because I have no knock sensor yet on this machine ... so I tend to be ... chicken....