This appears to be the SL 55 AMG pump:

New TI / Walbro Twin-screw Fuel Pump - TurboBuick.Com

This is either the TI-Walbro version of the pump or its the TI-Pierburg pump repackaged (TI owns both).

If so, its a good price.

 

I will check this out...thanks...for that price, even if doesn't work, I'm not out much

 

Why it's a mini screw compressor! Quick, mount some at the ends of the intakes LOL!

 

just like the oil pump on my Harley...it's always screwin' around..

 

Would hate to see you waste your time, if not the $$$. It is a good price though, compaired to what I paid.

 

So what your saying is that this doesn't work or help any, correct?

 

Well, what I'm saying is, if buying this pump or any other pump to resolve our type of leaning issue will not work.

I think we are on the same wave length.

 

Spill the beans man, there's only so many of us with these cars.

 

You need ot consider that the rail pressure needs to be about 60 psig to feed the injectors. Just saying Woody

 

i think bulldogger and slkgermany would disagree with you

 

I think this pump would be more efficient in the long run...not after HP per se...more reliable pump...

 

I have done what they said (install SL55 pump), they have not done what I asked ( provide max boost level and corresponding a/f).

Sent from G2

 

That works Doc, just didn't want you to buy it for the wrong reason.

Sent from G2

 

I appreciate that...but, both cars have some miles on them, so a new pump, especially this one at that price isn't a bank breaker...would be a good upgrade...not looking for anything else...

 

If you want to replace it because you feel you may have a fuel supply volume problem, you can determine this by connecting a fuel pressure gauge to the rail and attaching it (duct tape works lol) to the windshield. This way you can monitor fuel pressure from the cockpit under worst demand (WOT) conditions and look for fuel pressure dropping below the regulator set point (even if you've modified that).

 

I have a pressure sensor on my fuel rail and a Zeitronix/Dashdaq to monitor fuel pressure.... mine is adjusted(NW fuel kit) to 62psi and at WOT I see the rail pressure drop to about 48psi while sucking down gas..very interesting to look a the data log of the fuel pressure across a run....

 

What do your AFR's look like when it drops?

Sounds like you may have a fuel supply issue...the pump isn't keeping up with the demand. The regulator tries to maintain pressure by returning excess fuel back to the tank. When there is no excess, the regulator is closed off and the total volume of fuel is going out the injectors. When the injectors flow more fuel than the pump is supplying, pressure drops.

These constant-power pumps will supply more fuel volume at lower pressures, since it is fighting less against the head pressure. A possible solution (if lean) would be to lower the pressure, and increase injector pulse-width at WOT if possible. Unless there is no more inj pw and they are static, then the solution is more pressure (and possibly bigger pump).

Dropping fuel pressure is not always an issue. When the pressure is high at low-demand conditions, the PCM just dials back inj pw. At WOT, if inj pw is large enough and fuel pressure drops to a level sufficient enough to maintain AFR, then it's ok. However, almost always, there is no safety margin if the need for more fuel (hot day, bad gas, high boost, etc) suddenly arises.

 

Ive done lots of testing and adjusted my rail from 40 to 80+ PGIG. If your lean, jack up the rail pressure a few pounds. I got the fuel controller working with the Zeitronix open loop pressure controller and solved any leaning tendancy. The increasing boost pressure limits the EFFECTIVE pressure across the injector pintel reducing your fuel DELIVERY when you need it most. THis is why I cautioned that the pump must be rated to OPERATE at about 60 or a bit better. Wooody

 

I have the NW fuel kit with the Walbro pump and AEM FPR.... my AFR's are running between 11.3 - 12.3 at WOT after the EC re-tune last month and adjusting the fuel pressure... no leaning problems at all....

 

That's the key. Lots of pressure at low fuel demand conditions doesn't really mean much. Maintaining the set pressure at large (or static) injector pulsewidths at these demanding operating conditions verifies that pump capacity is sufficient.