Date: Tue, 18 Apr 1995 10:29:43 -0700
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: eugp@uclink3.berkeley.edu (Eugene C. Palmer)
Subject: Re: The Berg and springs
>I am planning on buying a stock motor with a new case and installing
>009, extractor w/single QP and dual Kadrons. Now, Berg is telling me
>that dual carbs means dual springs. He quotes some stats about valve
>train failure and such. He also warns that most builders do not
>correctly install and shim dual springs, which can cause a whole other
>set of problems. My question is this: do I order my engine with
>dual springs or go without? He doesn't say how often others screw
>this up. It would seem from his writing that stock single springs
>would give me more trouble than risking having someone screw up
>installing dual springs. Opinions? Oh, this would be a stock 1600DP
>going into a '71 bus. Thanks, Jim
Jim,
I, being a Berg fan and having read all the same stuff your reading, would
say that it mostly depends on your driving style. I have built several
engines since "going Berg" and find that spring wieght is mostly relative to
rpm's (of course). Any bus should definitely have shimmed, heavy duty
singles, and if your fond of hard climbing in third and keep it there until
you hit 60 over the crest of the hill like I do, get double springs.
However, I have two engines out with dual carbs, LW fly, CW crank that have
HD singles springs with baby dellortos (FRD 34's) on single port heads that
have lasted longer than my double spring, dual port, engines. With 6.7:1,
12.5 BTDC and regular gas (87) these engines have great throttle response,
power, no knocking and run really cool. Broke 210 degrees a couple of times
climbing out of Death Valley at 114 degrees air temp, but other than
that..... I did drive the double spring engines harder, 75+mph for hours on
end through Cal & Oregon, so it's not fair comparison. I have to disagree
with Ol Geno about the FRD 34 carb. It can do an air-cooled engine as far
as my experience has been. The Kadron is great too, and develops more
power, but the throttle response is happening on the FRD's.
You do have to be more careful with your valve train, use HD pushrods,
lashcaps, solid shafts, notch your lifters, and watch them. But you should
do that anyway in a bus. I check my valves every morning on the open road,
would've loved to get those hydraulics, but Ol Geno says no. I have a
theory that single springs would get better mileage than doubles, but I
wouldn't risk a valve failure on it. Doesn't the type IV have double
springs? Anybody care to comment?
I also have a theory that the single port head is a better heat dam (more
material) and cracks less.
I should mention that I have several carb sets for sale;
Dellorto FRD 34's with both single port upright and type III manifolds
Kadrons with both single port and dual port upright manifolds
Solex PDSIT 32/34 (l&r) with type III manifolds and factory filters with spares
Weber 40 IDF-XE with dual port upright manifolds, and velocity stacks
All have linkage, and are in good condition. Price is best offer over $175
for the singles and $250 for the Webers.
I will be selling these, along with lots of other stuff, at the Vallejo swap
meet this weekend so if your interested drop me a line.
Eugene
'71 you-know-what
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