Angry Gumby is getting near to it's first fire up! Woohoo! I still have the carbs to sort out though. I'm looking for a starting point for venturi
size and jetting. Any advice will be welcomed.
The engine specs.
2110cc 82 x 90.5
CB H beam 5.4 in rods
CB 044 heads 40/35 valves single HD springs (Mild port job)
9.0:1 Compression
Chromolly push rods.
Engle 110 Camshaft.
The Carbs
Dellorto DRLA40s
Venturis 32mm (too small! should be 36s?)
Main jets 135. (I'm thinking round about 150?)
Now here is where I get out of my depth as I do not have a Delorto book.
The 2 jets that screw in from the top .52.
Single jet that screws in from top. 95.
The 2 jets that screw in from the side. 33.
The carbs were Ebay items and are in pretty good nick.
What do you reckon?
Brendan:jesus
Dont worry about the 1 jet on top or the 2 on the side. The 2 on the top are the idle jets. The other things you didnt mention are the air correction
and the emulsion tube. They are in the stack with the main jet. Emulsion tube should be a no. like 9164.2
I have basically the same combo with more cam and heads, and 48 DRLAs. Im running 65 idles, 165 mains and 170 airs.
The 32mm vents will choke it, but your cam wont be pulling past 5500ish anyway.
I would try some .60 idles, 155 mains and 170 airs... it should get it running. Cheapest way to do it is go to an engineering shop and buy the
drills, only about 1 buck each.
Adrian,
Thanks for the info. I have access to a full set of number drills. Since you typed the response I found a nice exploded view of the DRLA carb on the
CB Performance web site that describes all the bits.
So from what I can work out I've got 180 Air correction, 135 Mains and 52 Idles. I also have a spare set of 36 Dels so I'll check the Air Correction
jets on them. Another site I found states that the 36s have 180 Airs as well from standard. What difference will this make? I might try to get hold of
some 34 or 36 mm Venturis also. I'll put a WTB add in the buy/sell section and see what happens.
Thanks again
Brendan:jesus
Hey, where is the del exploded view on the cb website? I run 40mm dels on my little 1776 and they are sweet.
Try this link
http://www.cbperformance.com/catalog.asp?ProductID=1245
It's the DRLA parts locator
:jesus