| [ Total Views: 602 | Total Replies: 4 | Thread Id: 8802 ] |
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 bond
Veteran Volks Folk
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| posted on July 26th, 2003 at 08:04 PM |
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in need of help - single or dual?
was curious what was more fuel efficient.. using a single or dual carb setup? (regardless of engine size)
any help, info, stories greatly appreciated.
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vassy66T1
A.k.a.: Marcus Vass
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| posted on July 26th, 2003 at 10:34 PM |
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I have had both a single (42dcn) and duals (36idf's) on my 1776cc with a mild cam and just the usual balancing of internals and getting
compression ratios right.
The motor is in my Kombi, and on a long trip with the duals I got 28mpg. That was sitting on 95-100km/h.
Round town it does quite well also.
The single wasn't any better, and may have even been a bit thirstier. Powr comes on a lot more smoothly across the rev range with the duals so
you don't have to work the motor as hard i found.
I think it's a matter of getting the jetting spot on.
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Doug Sweetman
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| posted on July 27th, 2003 at 11:44 AM |
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Jetted correctly, a set of duals will give better economy. Doesnt sound logical until you realise with a single you have such long intake manifold
runners that fuel can actually condense on the runners, thus requiring a richer ratio (more fuel) to make up for the amount that condenses.
At least I think thats what I read somewhere.
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 Bizarre
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| posted on July 27th, 2003 at 01:04 PM |
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Doug is right.
Futue te ipsum!!!
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lugnuts
A.k.a.: Mike
Custom Title Time!
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| posted on July 28th, 2003 at 04:01 AM |
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Blue L is right about Doug ive heard |
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Purple Martin
A.k.a.: Martin
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| posted on July 28th, 2003 at 08:52 AM |
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You should read this sermon by the excellent Bob Hoover:
http://osf02.ktu.edu.tr/~ulutas/hoover/dual.html
1959 red & white Beetle
1975 Kombi camper
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Secoh
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| posted on July 28th, 2003 at 09:02 AM |
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often by increasing an engine's output you can reduce fuel consumption. sound whacky? sure, but when you realise you dont have to hammer a larger
or tweaked engine as much as a small or stock one to get the same driveability, it obviously uses less fuel. (to a point of course :P)
I had a toyota crown once with a 2.8L six in it, which would get at best 350 to 400k's from 60L on the f3 freeway which I drive reguarly. it
wighed 1550kg and had high gearing to suit.
I fitted a 3.0L Supra turbo motor into it and instantly could get 600k's from 60L of fuel onm the freeway!
of course if I gave it heaps it'd go through that 60L in 200k's :o
If it aint broke,
Make it go faster!!  |
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