High knock count on nearly stock setup...

[coolnick]

I have a 90 GSX with a 14b and a MBC. I rewired the fuel pump and removed the lower honeycomb in the MAS. I logged some runs in 3rd gear at 15 psi and I got about 40 counts of knock and near 0 degrees of timing advancement (on 93 octane). I had to back the boost all the way to 12 psi to get the knock count below 10. I am thinking that a fuel pump may help out a little here. I want to run 16-18 psi if at all possible, will a Walbro 190 allow this, or do I need more of a fuel pump and a AFPR? Does the small screw in the lower section of the MAS make enough of a difference to bother screwing with it (no pun intended).

TIA

 

[coolnick]

Allright, I'll reply to myself here. I ordered the Walbro 190 low pressure and a G Tech meter. The G Tech was just for fun of course, but we'll see if the fuel pump actually helps. Thanks for the great responses!

 

[1994supertalon]

While you're at it replace the knock sensor. Your car is older and chances are that the sensor is bad.

 

[coolnick]

Thanks supertalon, I'll order one up. Does anyone know the torque spec for the knock sensor? Should I bother messing with the small screw in the MAS?

And what the hell is this? ----->

 

[coolnick]

And is there a good source for knock sensors aside from the dealer? My usual import parts places do not carry them.

 

[LandoAWD]

www.partznet.com

Cheap, and you'll get it in 2 days or less.

Torque specs, I can' EXACTLY remember, but its just a hair past hand tight.

 

[nowayout]

FYI Torque is 10 ft/lb

 

[coolnick]

Thanks for all the replies. The fuel pump should be here Friday, along with the G-tech. I got my RRE downpipe today, I will log all my runs before and after each individual upgrade. I am surprised that nobody has responded to the other aspects of my original question. I know that the fuel pump should add what I need, and that the small adjustment screw in the MAS should give me a little more margin, but I would like to hear it from someone that has been in this same position. Is 18 psi a good idea with a 190 lph pump on a relatively stock setup and no AFPR? I guess it really doesn't matter, as I will find out this weekend!

And I'll be sure to tell you bastards all about it:laugh: