walbro 307 pump big enuff?

[101prf]

I just installed a bb65 turbo and mototron 60# inj, now the car sputters and full acceleration. It feels like it's leaning out and has had a cupple small backfires. the scanmaster is not showing lean (o2's 765-820),but the plugs look like it's been lean. I have tried a new o2 sensor. I have a walbro 307 pump that was fine with the old 42.5# inj. Is this pump big enuff for the 60# inj?

 

[artrenee10]

Nope....

Get a "new" 340 and hotwire it if you haven't done so already.
Steve Chambers

 

[101prf]

yeah I was talked out of the 340 and into the 307 with my old combo. I was told the 307 was more than i would need but it doesn't look that way now.

 

[salvageV6]

I'd put a fuel pressure gauge in the window before I pulled the tank.

 

[2QUIK6]

Could be lots of other things could cause that. Sputtering and poping at WOT and the O2s are up that high, I would suspect the coil/ignition.

How much boost are you talking about at WOT when it starts sputtering? The 60# and the 307 should be plenty for regular street setup with 18-20# max boost. With a GT61 turbo, I've ran 27# of boost with my 60#ers and 307 pump without any issues...injectors were only pushing about 75% DC.

If you're getting 1# of fp increase per # of boost you should be ok.

 

[bruce]

I just installed a bb65 turbo and mototron 60# inj, now the car sputters and full acceleration. It feels like it's leaning out and has had a cupple small backfires. the scanmaster is not showing lean (o2's 765-820),but the plugs look like it's been lean. I have tried a new o2 sensor. I have a walbro 307 pump that was fine with the old 42.5# inj. Is this pump big enuff for the 60# inj?

Folks have said there's just no way with 60's that I need dual pumps. Yet, when only running with one, the motor just lays down when I get to 5 PSI of boost. Oh, and that's a double pumper with 340s.

IMO, I can't see risking going lean, with all the damage that can do.

 

[TurboTR]

A single 307 will go near the ~ 120 mph range by itself. Sounds like it needs tuning lol...

TurboTR

 

[ChrisChow]

Wide band the thing to know for sure.
I use Innovate Motorsports verision. There are others out there.

I personally would recommend a 340 series Walbro in your application.

Sorry to say something negative about narrow band readings from the scanmater but they really are not a substitute for a wide band system.

 

[101prf]

The plugs electodes were white in all cylinders, so i think its safe to say i wasn't seeing correct o2 readings. I took it out for a quick check and noticed the volts on the scanmaster drop to 12.2-12.4v, it idols at 13.8v on the scanmaster(14v @ the battery with a meter). The pump is hot wired but is it normal to see this drop? (I've never looked at volts while accelerating before). I'm surea charging system problem could cause fuel and other problems.

 

[TurboJim]

If I remember right, and I may not, the diff with the 307 and 340 was the bypass pressure. I think I recall the 307 bypassing at mid 60's on FP, and if you're at 20psi, you're in the mid 60's with FP. If you have a stock headed car (I didnt read your sig) then I'll assume you're running high boost and this is a problem. You may consider upgrading to a 340, or at minimum shimming the 307's bypass. I'd get with Jack (racetronix or Cottons, or Joe Lubrant on this. I believe Joe did PTE's flow testing/recording and would know this off the top of his head. I'm sure either Jack would know too.

 

[101prf]

So with a base pressure at 45psi and 20# boost I'd be at 65psi and could bypass. would this have happened before with 42.5inj, the car ran good until I replaced the turbo and injectors.

 

[101prf]

yeah I was talked out of the 340 and into the 307 with my old combo. I was told the 307 was more than i would need but it doesn't look that way now.

This reads like I'm putting the blame on on someone else, not how I wanted it to read. I've changed my combo since the pump was ordered.