Tag: Bipipes
WOTbox fixed, replacement bipipes, Walboro 255 pump, and SMIC shrouds
by Matt on Jun.24, 2010, under Logs, Mods, Parts
The car got a few new parts over the past 3 weekends. WOTBox, ER intercoolers, new charge pipes and a larger fuel pump.
A few weeks ago I installed my WOTBox. It’s a hardware based 2-step launch control.

It wires into the clutch & accelerator pedal and cuts the ignition at a predetermined RPM when you have both pedals to the floor. The install was very easy and the color instructions that N2MB includes are wonderful! I haven’t been able to get the thing to work correctly though.. When it’s set up it incorrectly cuts the ignition when the clutch pedal is out. But I think I’m setting it wrong. I learned last night that there’s a secondary rev limiter “hidden” in Motronic that you can enable. I’m trying to find out more about it and see if it’ll build as much boost as the WOTbox.
Next up was the replacement charge pipes. The first set of charge pipes I was sent didn’t fit well at all. I think they were meant for another car. At first I couldn’t get a lot of sympathy about the poor fitment. A few months later I saw some install photos of the pipes on another person’s car and could tell an obvious difference. So I emailed photos of my pipes and the fitment to the actual guy who fabricated them at Vast. He immediately shipped me a replacement set.
Old pipes, the meth nozzle rubbed right into the timing cover.

New pipes. They fit sooooo much better.

At the same time I was installing the charge pipes I also installed the larger ER intercoolers. The install was annoying and I ended up cutting more than I probably needed to. They fit alright, better than the RS4s. It was still tight on the passenger side with the AC condenser very close behind.

I ran some intake temp logs last night and it showed a measurable improvement.
The old RS4 intercoolers + meth dipped to ~15* above ambient and rose to ~30*

The new ER intercoolers + meth stay a little flatter. They dip to ~5* above ambient and rise to 15*.

So an improvement of 15* up top. Not bad, I guess. Not really worth the $$ I spent on the ICs but I might spend some time revising my “custom” shroud setup.
Finally, the most recent install was a Walboro 255lph pumpthat I did Saturday @ Chris’ bonanza. Between the heat, my allergies and the gasoline everywhere it was a pretty miserable task. I didn’t tighten the top lid down enough and it leaked all over the place on the way home, so I spent some time Sunday making sure everything was tight. The good news is I have enough fuel now.
Pink is before on the stock fuel pump. Too lean.
Red is the Walboro. Getting better.

I am a B5 S4 owner that operates under the delusion that a single car can be comfortable, attractive, and fast. Join me as I journal the repairs, maintenance and mods of my S4 in the attempt to realize a possibly unobtainable goal.