Hey everyone. Just wondering what your dub revs at when driving at 100kph? I have never had a gauge so dont know what my kombi's and type 3's have done over the years. Pretty high by the sound of it.
There is a detailed article on this in the August 2009 issue of the Club VW Sydney magazine 'Zeitschrift'. Go to http://vwwatercooled.com/mag/mag/history.html and download it as a
PDF.
It explains how road speed and engine speed are connected, and how you work out one from the other. Some of the examples mentioned are:
1600 Kombi - 24.95 km/h per 1000 rpm - 4409 rpm at 110 km/h
2-litre Kombi - 29.67 km/h per 1000 rpm - 3707 rpm at 110 km/h
1200 Beetle - 29.70 km/h per 1000 rpm - 3704 rpm at 110 km/h
1500 Beetle - 31.42 km/h per 1000 rpm - 3501 rpm at 110 km/h
Superbug L - 32.01 km/h per 1000 rpm - 3436 rpm at 110 km/h
Golf Mk5 GTI - 41.57 km/h per 1000 rpm - 2646 rpm at 110 km/h
Modern cars are much taller geared than older cars.
Sweet bro, that pretty much explains it all. Wow, im still amazed how much a 1600 kombi revs at 110km/h, especially compared to the new golf....
back in the 50s and early 60s
that amount of revs was common in most cars...
the VW engine was advertised as slow revving...
and was one of the first cars to have Overdrive as standard
[compared to other cars back then]
Holdens & Fords etc only had 3 gears..
many automatics had two gears.. Fordomatic was one..
LEE
What about using 205 70 15 tyres on the rear
as Hankook Centrum are 668mm diameter
where as 165 80 15 Hankook are 624mm diameter
wheels are going 15.4 kms slower with the 205 70 x 15 tyres
so engine is going slower too...
I wonder what this does to acceleration??
is it worth it???
LEE
PS: using 14 or 13 inch wheels and tyres will give you great acceleration... but poor fuel economy.. etc..
my manx revs at about 4000 at 110km/h and my 60 beetle is about 3500 at 110km/h
matt
Our bus is 3500 at 110kph with a 2 litre box.
it all depends on tyre height
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In case you want to work it out yourselves, ALL three variables are needed :
Km/h = (RPM x Circ x 0.06) / (Gear x Final)
Where Km/h is the calculated speed
RPM is the engine revs
Circ is the tyre circumference (depends on the wheel and tyre size - can be measured by marking the tyre/road with chalk, rolling forward one tyre
revolution and marking again)
0.06 is mathematic constant that converts metres/minute into kilometres/hour
Gear is the gear ratio (usually fourth gear, but any gear works)
Final is the diff ratio
Let's use the Superbug L as the example. It has 15" wheels that wear 165/70-15 tyres - a rolling circumference of 1.923 metres. The 4th gear ratio
is 0.93, and the diff is 3.875. The calculation for 1000 rpm is: (1000 x 1.923 x 0.06) / (0.93 x 3.875) which equals 32.02 km/h.
To get the engine RPMs at any speed - say 150 km/h (!), you go 150 / 32.02 x 1000 = 4684 rpm.
You can change any or all of the three variables - wheel/tyre, 4th gear and diff - and get a different result.
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there are online calculators too for RPM etc.. if you go to
http://www.cbperformance.com
http://www.csp-shop.de
The only way you would actually know for shore would be to put a tacho on and see.