Jetting advise for 2110 and 45 DRLA's

[PH1303]

Hi

Hoping for a bit of advise from the lounge members. We are going to change my brothers 44 IDF's to 45 DRLA's, and hoping for some recommendations regarding baseline jetting for the Dellorto's. Engine spec are as the following:

82x90.5
5,5" rods
Web 86B
CB 1:1.4 rockers
9:1 static compression
1 5/8 merged header
G03 heads with 39x35 valves

When the engine was almost new, it made 152 hp and 213 Nm with the 44 IDF's. The Dells are with 38 mm venturies...


/Peter

[javabug]

Very, very close to my engine spec, but with 48 DRLAs and 36 vents. I have to double check my notebook, but I'm almost positive it's the following:

60 idle
160 fuel
190 air

Depending on a few other factors like altitude and fuel type, it could be a slight bit on the lean side for you. But it will get you on track.

[DWL_Puavo]

I second Mike's opinion - if you have the most usual 9164.2 emulsion tube, those jettings should be a good starting point. Also 38mm venturies seem like a good size for you heads, cam and engine displacement. You may need 65 idles (~17% bigger than 60) and maybe 170-175 mains (~13-20% bigger than 160). Most usual air correction jet is 180 and it should also be fine.

[javabug]

I checked my notes, and I'm actually using the 65 idle jet.

[PH1303]

Tanks for all the advise. Much appriciated.

We have now checked the carbs, and they are equipped with:

Idle: 58
Main: 160
Air: 200
Emulsion tube: 9164.2

Proberly a bit on the lean side, but maybe okay for start up.

[javabug]

It'll run like that, but you'll probably need 60-65 and maybe the 180.