Weber 32/36DGV verses the Weber 38DGES

yodta
(pooh bah)
Wed Apr 13 2005
06:05 PM
yodta
(pooh bah)
Thu Apr 14 2005
12:44 AM
Sarge
(carpal tunnel)
Thu Apr 14 2005
02:20 AM
yodta
(pooh bah)
Thu Apr 14 2005
04:14 AM
Sarge
(carpal tunnel)
Thu Apr 14 2005
01:14 PM
I tried taking the primary air up to 175 to see if I could weaken it a bit, but all that did was make the primary come in later, and it
was flatter up through around 2500 until I gave it more throttle and then it would pop, which is no good.
I also tried taking the p-idle down to a 60, but that was way way too lean. I went from the mix screw being at around 2-1/8 up to
about 3 turns out!
Anyway, just to get a better feel for what it's actually doing, I'm considering the following combinations: a 130 main with a 155 air,
and a 135 main with a 170 air, just to see and get a better feel instead of relying on the meter.
Re: Weber 32/36DGV verses the Weber 38DGES
Oh, by the way, very important -- the Aux. Venturies in each of the throats of my carb are both 3.5. I thought the secondary was a
4.5, but it's not.
I think I'm gonna make an air filter spacer out of the Garolite, too. kinda figured on the 1/2" to 3/4" rise.
check with Pierce on the insulator blocks. they have one on their site for the 32/36 and one for the DCNF as well.
http://piercemanifolds.com/accessories.htm
Re: Weber 32/36DGV verses the Weber 38DGES
I just ordered some main jets and an F81 emulsion tube this afternoon. I got a 125, 120, and a 115. I'm not sure the way to go is
down, though, but as I said, still trying to get a feel, and open to experimentation.
the F81 tube is identical to the F50 except it has two small holes at the base of the tube which would, I imagine, reduce the
mixture weakening effect at lower rpm.
got some gasket material and the insulator, too.
Re: Weber 32/36DGV verses the Weber 38DGES
First, you shouldn't have changed jets until you drove it on that F6 tube. What I'm trying to do is show the difference in timing with
the current jetting . As your test shows, the primary has plenty at low revs with the current combo but runs out a fuel at higher
velocites. The noise with no gain is too much raw fuel without air mixed into it from the tube's configuration. If you drop the main
jet down in size you will have to drastically drop the air jet as well , probably in the range of a 160. The F6 tube will show if you
have enough velocity or just a large volume of air moving through the carb . This initial run is really showing the secondary as
well as (possibly) the primary needs a larger venturi installed. Not sure why you have 3.5's in the auxilaries, I thought most
engines specified over 1600cc would get 4.5's in the secondary for sure . One real issue here is how well that manifold is
atomizing the fuel , the F6 so far shows that it is not . This is not totally a bad thing and can be dealt with by adjusting the carb. If
this is the case you may just have to go with a tube that is basically the same layout as the F50 but with smaller holes or a
smaller outside diameter . Too bad we couldn't hit a dyno shop and spend a couple days dialing it in....
Sarge
Re: Weber 32/36DGV verses the Weber 38DGES
I'm actually going to change back to the jetting tomorrow as it was prior to installing the F6. sorry, got excited
who is your parts supplier? Pierce is showing only 3.5 aux. venturis for the DGV & DFV series carburetors.
Quote:
The F6 tube will show if you have enough velocity or just a large volume of air moving through the carb.
the F6 will show what?
so after I go back to the previous jetting, what do we do next?
Re: Weber 32/36DGV verses the Weber 38DGES
The high jetting you were running tells me the air moving through the carb is not doing so at a very high velocity . This is just a
lack of signal, probably from the intake having a bit too large of an internal runner diameter. Offenhauser typically runs pretty
large runner bores to help larger valves and high compression work like it should . As a result the air moves slower, but more
volume. The speed of the air going through the carb's venturi is the signal the carb recieves. You can run into the same problem
if the carb's main venturi diameter is too large. Say, if the 32mm throat had a 30mm choke diameter instead of 27mm, the signal
would be weaker to the auxilary venturi . Same deal with the secondary, hence a lot of the 32/36's having a 4.5 in that side. The
4.5 aux's I refer to are from a 38DGAS and are not a total direct fit, most a bit wider and guys use them to repair loose fitting
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