I think all we got to do with your car was a couple of runs up and down the 10 in your neighborhood. I'd have to go back and look at the logs - it's been a while.

Yeah - your car was very rich (according to the feedback) above 5000 and wasn't really responding to changes in the fuel map.
This is consistent with a fairly severe imbalance between the fueling in the front and rear rotors.

That said, your MAF was reporting way more air than what was to be expected with your setup at that boost level, so there could be several different overlapping mechanical things going on there.

 

maybe because the VDI was left open?

all of the injectors where removed and cleaned nothing was found out of the ordinary, your next guess was the fuel pump, which is a walbro 255 from BHR. I might believe the fuel imbalance if one rotor failed, not both. both failed.

I don't think most of the OEM widebands can handle the heat and pressure in a pre-turbine setup at WOT. which seems so especially when the stock is saturated a good 2 seconds after a wot pull on most setups. even if for 1 second its saturated it won't respond to a lean spike.

the maf flows whatever g/s you want it to, I think you really mean the maf was reporting a high voltage, which I might agree with, right now with 40degree intake temps 5psi @ 7700rpms is between 4.53v-4.65v. same exact intake setup

 

No real effect on net airflow - just a bump at worst.

You tested them in the factory rails with the factory injector drivers?

I no longer use a Walbro for good reason.

Both rotors "failing" - while highly unusual - indicates nothing about fuel delivery.

The OE WBO2S is neither sensitive to the "pressure" or heat pre-turbo nor does it "saturate". A lean spike, should it occur, will register just fine. The rich, post-pull registration is real and typical, not an indication of the sensor flat-lining.


Though that is essentially a correct statement, the car wouldn't run correctly if the measurements were more than a couple of grams off from reality in either direction (unless the entire curve is moved by the same amount, in which case it would correlate with the commanded fueling values, anyway).

This would be the same thing since I use, effectively, the same range of MAF values on every car I tune.

 

Disassemble would show uneven fueling. It did not.

I can agree to disagree about the wbo2s

So what is your fuel pump now?

 

Off Topic Posts have been deleted.

 

Thanks alnielsen!

 

any updates on this build ???

 

subbed.

 

Get a wideband placed 10-12 inches past the turbo in the downpipe!

 

bored, bump for updates?

 

Updates?

 

Ok, I know it's been a long time, I'm still around and kicking. Just dropped motor number four in last weekend. The built motor lasted for 1000 miles before it it let loose. When I say let loose I mean both rotors, 0 compression, 0 warning, and no idea what happened. That was two and a half years ago. I've reached out to Kane for tuning assistance this time around. Once I'm through the break in (1000 miles) I'll start tuning.

On a side note, I installed a set of BHR's motor mounts and they are a work of art. I have a dampener and before I hooked it back up I gave the motor a good shake and it didn't rock at all. One thing I wasn't expecting is what it did to the shifter feel. It doesn't shake, and no mater how hard you turn in, the gears are where they should be. Anyway, highly recommend them.

Hope all the other old guys are still around and doing well!

 

Damn that sucks! Sounds like you were tuned to the edge and got some bad gas.

 

Glad to see you back, I am 20,000 on my rebuilt (Pineapple Racing) engine, been running 8-10psi most of the time. But Steve Kan tuned mine, I highly suggest an in person dyno tune if you can get it.

 

Sorry to hear about your issues Wanted.
It might have been the original tune , but if the tune was good at one time , it just doesn't go 'off' by itself at another time without some change happening within the system.
One thing that many people don't realise about maf tuning is that any slight change in the way your intake is set up can totally screw up your tune . Leaks also play havoc with it .
In this respect a MAP tune is better but if you are aware of what can cause a maf tune to go west and deal with it , a maf tune can be better than map.

With guys i've been working with lately , I am really pedantic about getting them to get a good intake setup and once we get that right , tell them to mark everything up so that they put it back together exactly the same every time .

 

I have two theories as to what happened, first being something got ingested, second being we got too liberal with the porting and a seal slipped. Neither of which really have anything to do with the tune, but given events leading up to failure and what not, that's my guess. Suppose I mispoke when saying the tunes were a commonality between failure given my personal thoughts, but I was trying to keep things simple. Either way I'm done begging for tunes.

Edited post to reflect that

 

Yeah, these two points cannot be stressed enough..

 

That sucks to hear that it let loose so soon. Always wondered what happened to ya.