Fine tuning carb for 50hp build

[iggy320]

I have a few things I need clarification on.

 

- To remove or not to remove pilot air jet on fcr39

- How much richer do I need to run if I pull out SSW pipe quiet insert?

 

I have the 440 kit, fcr 39, stage 2 cams, base gasket mod, mrdssw pipe with quiet insert.

 

I'm at 700ft above sea level.

 

Carb is set as it comes from the TT store:

160 main jet

45 pilot jet

EMR needle on clip 3 (or whatever it comes with from the store).

Pilot air jet is STILL IN

 

Should I remove the PAJ?  I removed it once when I still had my RS-2 and it ran like crap!!  WAY too lean with the 160MJ.  It doesn't make sense to remove this thing at all, because when I put it back in it ran great again.

 

I seem to be currently running lean on the PJ because I have some slight popping on decel and slightly less than snappy response on 1/4 throttle.

 

I am thinking I could go with 165 MJ 48 PJ and remove the quiet insert and PAJ.

 

Do I need to put in the emn needle and/or change clips..?

[hinksy]

If it is the FCR/MX then you should remove the pilot jet , if it is the slant body FCR then it stays in , greg

[iggy320]

But it ran terrible when I took it out with the RS2... won't it just make it leaner?

[Craigo]

 To remove or not to remove pilot air jet on fcr39.....Remove it

- How much richer do I need to run if I pull out SSW pipe quiet insert?......155 main jet is ok (below 3,000 ft)

 

EMN Needle , clip 3 is what you want....

Do the O ring mod

Are you sure you didn't remove the Main Air Jet by mistake..?

[iggy320]

Okay so what I've noticed is I've been running way rich with the BB kit with my 160 main.  When I pull the throttle past 1/8 or 1/4 some smoke comes out of the exhaust.  I can smell gas, and when I pull the carb out there's smoking coming from the manifold.  Definitely rich.

 

I think I need to grab a 155 main before I do any of this other stuff.

 

I did quickly try and remove the PAJ again (I am removing the correct one) and it ran even more rich (???) and I tried the emn needle, It didn't really change much.

 

I even did the o-ring mod and got my spray going at about 1 second, and it ran even richer still, smoke going all over the place.  I set everything back to the way it was.

 

I'll be grabbing a 155 main before I do any more adjusting.

[OverSquareEng]

Okay so what I've noticed is I've been running way rich with the BB kit with my 160 main.  When I pull the throttle past 1/8 or 1/4 some smoke comes out of the exhaust.  I can smell gas, and when I pull the carb out there's smoking coming from the manifold.  Definitely rich.

 

I think I need to grab a 155 main before I do any of this other stuff.

 

I did quickly try and remove the PAJ again (I am removing the correct one) and it ran even more rich (???) and I tried the emn needle, It didn't really change much.

 

I even did the o-ring mod and got my spray going at about 1 second, and it ran even richer still, smoke going all over the place.  I set everything back to the way it was.

 

I'll be grabbing a 155 main before I do any more adjusting.

 

What color is the smoke?

Edited May 14, 2014 by Wisconsinite762

[iggy320]

White smoke.

[OverSquareEng]

White smoke.

 

If it is running rich the smoke will be dark grey/black.

 

White smoke is usually caused by burning coolant.

[iggy320]

Come to think of it, there was some moisture in the end of the exhaust... I'll check the coolant cap.

 

I may need to tighten up the 4 bolts underneath the cams...

[Craigo]

Okay so what I've noticed is I've been running way rich with the BB kit with my 160 main.  When I pull the throttle past 1/8 or 1/4 some smoke comes out of the exhaust.  I can smell gas, and when I pull the carb out there's smoking coming from the manifold.  Definitely rich.

 

I think I need to grab a 155 main before I do any of this other stuff.

 

I did quickly try and remove the PAJ again (I am removing the correct one) and it ran even more rich (???) and I tried the emn needle, It didn't really change much.

 

I even did the o-ring mod and got my spray going at about 1 second, and it ran even richer still, smoke going all over the place.  I set everything back to the way it was.

 

I'll be grabbing a 155 main before I do any more adjusting.

 

The pilot air jet is on the left as you look at the back of the carb, main air jet on the right..