Mikuni PHH pilot screw question

[EricB]

Pilot Screw is #65 in attached diagram.

With me still unpacking from a recent move I can't seem to located my PHH manual anywhere....

Can someone remind me what the base setting on a 44PHH is for the pilot screw is?

2 turns out from seated?

2 1/4 turns?

And turning it CW makes it leaner & CCW makes it richer, or vice versa?

Someone remind me please...

Thanks,

-e

[jmortensen]

1.5 turns, then do not adjust them anymore. Get the size pilot that runs well with 1.5 turns out. That's the advice I was given from those who know better than me. CCW makes it richer.

[EricB]

Aha! Exactly the kind of advice I was after... Thanks!

My pilot screws are "40" size which was the default size for my PHH 44.

I've gone one size bigger (155 vs 150) on my main jets but otherwise everything else is stock.

Thanks again.

-e

[jmortensen]

Your pilots are 40s??? I think I'm using something in the upper 60s. 67.5 I think. 40 is probably way too small unless you have a really tiny cam. I remember when I first installed mine it came with 50s and I kept on going bigger and bigger and bigger to the point where I thought I was doing something wrong. Then I installed a narrowband O2 in the exhaust and went bigger and bigger and bigger still til I finally got what I wanted.

[gundee]

If the jet is a 40 size, then you are probably talking about the pump jet and not the pilot.

[EricB]

duh...

my bad.

pilot screw isn't sized.

It is indeed my pump jets that are size 40... I have a stock L24 cam - no lumpy cams ... yet.

You know what, you guys that have been playing around with PHHs longer than the rest of us... you really ought to put a little do's and dont's list FAQ together specifically for PHH carbs... The manual (when you can find it) only gets you so far...

One of my friends (Dave with the flat black Z) was at an informal Club 4AG drift event at Camarillo airport some months back and was approached by one of the visiting Japanese "experts" in attendance. The guy took one look at the set of PHH triples and quickly made some suggestions... do this, don't do that, adjust this like this... the guy basically went to town on it... his car rips as a result...

I'm guessing you guys put your knowledge together and we could get something pretty useful of it, no?

What do you think?

-e

[EricB]

I do have an O2 sensor plumbed in my header collector... it is however a single wire Bosch off the shelf unit connected to a cheap $30 A/F gauge. A $200 Halmeter it isn't... but I figured some indication of what my mixture is like is better than none...

For what it's worth:

Runs a bit rich (smells like it) under 3000rpm

Feels pretty good from 3000-5000rpm

At WOT it can slightly detonate from 5000 to redline

-e