sorry another jetting question! since +3 crank

[craigz9876]

hi so ive found out im not running a 38mm keihin pwk its a 36mm keihin pwk. (like a dumbass ive measured the outside diameter) anyway, heres my mods:
I'm running a airsal bbk with just polished up exhaust port, a DMC alien pipe, +4 timing mod and a high flow airbox with a k and n filter, vitos +3 crank. any in the process of getting a redesigned head.im currently running a 68 and 170 jets, but i did a plug chop today and the plug was white not even marked. and im really struggling to get in the band only since the vitos crank just finished running it in. ive done a leakdown test all good (after spending 2 hrs looking for a leak, turns out my tester was leaking).
but i would just like a rough figure where to start with my jets so i can order a few either way, or just what jets a few of you guys are running with a similar setup.
thanks craig

 

[Surfrjag]

Those jets seem rich. Have you checked the float height on that carb? You should be close with a 45pilot and 165 main.

 

[craigz9876]

No I've not checked it. Will have to look in to it. It was fine before the stroker but the plug didn't even tan still looked new after a chop

 

[ken84]

hmmm well imo if its still white like that id think your way lean. id try a bigger main jet. what premix ratio are you running? what gas octane?

 

[scotj77]

sorry I have't been folowing your build or anything. so I'm assuming you've done a leakdown. what plug are you running? where is your needle set? why the hell are you running an alien pipe on that bad ass jug? I don't think that pipe could keep up at all with the engine mod's and carb you have. I personally would get a smaller carb or a better pipe. how did you perform your plug chop? just trying to be thorough

 

[craigz9876]

The plug is a br8es. The DMC came on the quad I'm saving up for a right bend once I'm back up and running. I got the quad warm. Changed the plug then full throttle 1st thru to 5th shut off then chopped the plug. Is this correct? How far do you usually have to reject with the stroker?

 

[craigz9876]

Sorry forgot to mention I don't know how to do the needle is the a how to?
It does have a number 6 stamped to the underside of it if that makes any difference?

 

[scotj77]

forget about the needle for a minute. did you do a leak down test on your motor? Also you need a new plug. do not get the br8ex, get the b8es plug. you do not need a resistor plug. that is what the R stands for.

 

[craigz9876]

I've done a leakdown all is good holds pressure. But I've never plug chopped so I could have been running lean before I rebuilt

 

[craigz9876]

found out the carb is a 35mm as i searched the number on the side (70r) so how does this look towards my jetting?

 

[scotj77]

I am runnin a 3mil stroker with a KOR agg trl port on a stoc cylinder with a Kehin 35mm airstriker and my jetting is close at 152 main and 42 pilot. you should def be higher than I am I would think but that pipe is probably slowing you down so.... hmmm you kinda got me stumped. how far did you run it at wot

 

[craigz9876]

Prob about 150yards. From first to top end of fifth I did it. How much difference does 1 jet up make or would I have to jump up a few to try it? Just been for some jets but my local shop don't stock them so gonna order some. Does it make much difference running a k and n filter compared to a foam one?

 

[scotj77]

you need to run it at wot for much further than that. a half mile would be better. that is probably why you got no color

 

[craigz9876]

So I need to hold it in full throttle in 5th a bit longer then? Think I'm gonna upset 1st before I try it as I can't hit the powerband at the min it just chokes when I get there

 

[scotj77]

I think you are jetted way rich it just didn't show any color bc you didn't run it long enough

 

[craigz9876]

so i bought 2 jet kits today got a 150 to 172 and a 180 to 205, will check the float height tomorrow then try to do a plug chop then photo it. so are we saying 1st thru to 5th then hold 5th? or try to hold each gear aswell as 5th?

 

[scotj77]

run it like you were drag racing someone. try to max it out as fast as it will go. I even go into 6th. then hold it there for a good ways. then kill it while at wide open throttle

 

[craigz9876]

So I down jetted to a 155 main today did a plug chop and it was a really light brown will post pics when I get home what is the ideal colour for a plug chop? Cheers craig

 

[ken84]

light brown is good! you can go up one size if you dont feel safe at the jet size you have now. but id leave it right where your at.

 

[craigz9876]

done a plug chop this is with a 165 main hows this look?