Jetting Kits, what do you do?

[michael950]

Just curious what jets people have use when they jet their carbs, do you have a kit of jets or just get recommendations and run those?

I will be switching to 44mm SBNs, and have been told a good start is to get the jets 10 up and 10 down from stock settings. Even at 2.50 / jet that is 20 jets for main and 20 for pilot = 40 jets total.

$2.50/jet x 40 jets = $100 * 2 carbs = $200 in jets

$15 per n/s x 4 = $60 x 2 carbs = $120

$2 / spring x 4 springs = $8 * 2 carbs = $16

200+120+16 = $336 in jetting. :scared:

All prices Riva.

 

[Matt_E]

He. Yeah, I've been down that road. Get a good estimate what your jetting should end up at. Then get all sizes within 7.5 jet points (whatever). Have a all spring sizes.

I don't really see another way to do it. The better your estimate, the less money you spend.

 

[SuperJETT]

I think most people mean jets within 10 points up/down, meaning if you're starting at 120 highs, you'll need 110, 115, 125, 130 jets. For the lows, they are in 2.5 increments so 110, 112.5, 115, 117.5, 122.5, 125, 127.5, 130. So that would be 22 jets, though you can probably get a good starting point from someone on here and only go 5 points up/down and be close.

Just curious what jets people have use when they jet their carbs, do you have a kit of jets or just get recommendations and run those?

I will be switching to 44mm SBNs, and have been told a good start is to get the jets 10 up and 10 down from stock settings. Even at 2.50 / jet that is 20 jets for main and 20 for pilot = 40 jets total.

$2.50/jet x 40 jets = $100 * 2 carbs = $200 in jets

$15 per n/s x 4 = $60 x 2 carbs = $120

$2 / spring x 4 springs = $8 * 2 carbs = $16

200+120+16 = $336 in jetting. :scared:

All prices Riva.

 

[crammit442]

I think most people mean jets within 10 points up/down, meaning if you're starting at 120 highs, you'll need 110, 115, 125, 130 jets. For the lows, they are in 2.5 increments so 110, 112.5, 115, 117.5, 122.5, 125, 127.5, 130. So that would be 22 jets, though you can probably get a good starting point from someone on here and only go 5 points up/down and be close.

H.S. jets come in 2.5 sizes also. I personally have never needed jets in 2.5 increments. Whole sizes are normally sufficient for me.:biggthumpup:

Charles

 

[Matt_E]

Having the guy that built/ported the engine know what he's doing helps to cut down the guess work significantly.

Unfortunately for me, that guy was myself. So, it took me a while to get it dialed in. However, I am confident that I have the best possible jetting for my setup now.