| [ Total Views: 1497 | Total Replies: 7 | Thread Id: 109229 ] |
|
|
 hpnotch
Seriously Crusin Dubber
Posts: 133
Threads: 28
Registered: November 11th, 2012
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on June 10th, 2015 at 06:16 PM |
|
|
Engine RPM and road speed
I've recently fitted an old Smiths tachometer in the Type 3.
Does anyone know of tables that exist to give an indication of engine RPM and corresponding speed?
Currently the tacho reads about 2700 rpm @ 50 mph in 4th gear, running on standard rims (15 in) and tyres. Does that rpm sound right?
|
|
|
adlbeetle66
A.k.a.: Denver
Custom Title Time!
Under the car.........again!
Posts: 1476
Threads: 98
Registered: August 15th, 2014
Member Is Offline
Location: Capalaba, Brisbane, QLD
Theme: UltimaBB Streamlined2
Mood: ICH BIN VW NUSS
|
| posted on June 10th, 2015 at 06:23 PM |
|
|
Not sure if this would help?
Its a type 2 though...
http://www.type2.com/library/misc/calcspd.htm
|
|
|
1500S
Custom Title Time!
Posts: 1418
Threads: 73
Registered: March 28th, 2005
Member Is Offline
Location: Nth Richmond, N.S.W
Theme: UltimaBB Pro Blue ( Default )
|
| posted on June 10th, 2015 at 06:47 PM |
|
|
| Quote: | Originally
posted by hpnotch
I've recently fitted an old Smiths tachometer in the Type 3.
Does anyone know of tables that exist to give an indication of engine RPM and corresponding speed?
Currently the tacho reads about 2700 rpm @ 50 mph in 4th gear, running on standard rims (15 in) and tyres. Does that rpm sound right?
|
Somewhere in the distant past I seem to remember that a Type 3 with a diff ratio of 4.125 : 1 and the standard Type 3 gearbox the top gear road speed
was around 19.8 mph/1000 rpm.
|
|
|
hpnotch
Seriously Crusin Dubber
Posts: 133
Threads: 28
Registered: November 11th, 2012
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on June 10th, 2015 at 08:40 PM |
|
|
Thanks for the replies -based on that info 26/700 rpm @ 50 seems about right then
|
|
|
grumble
Son of Jim - Creator of Good
Posts: 2668
Threads: 53
Registered: June 10th, 2008
Member Is Offline
Location: Taree
Theme: UltimaBB Pro Blue ( Default )
Mood: happy all the time
|
| posted on June 10th, 2015 at 09:14 PM |
|
|
| Quote: | Originally
posted by 1500S
| Quote: | Originally
posted by hpnotch
I've recently fitted an old Smiths tachometer in the Type 3.
Does anyone know of tables that exist to give an indication of engine RPM and corresponding speed?
Currently the tacho reads about 2700 rpm @ 50 mph in 4th gear, running on standard rims (15 in) and tyres. Does that rpm sound right?
|
Somewhere in the distant past I seem to remember that a Type 3 with a diff ratio of 4.125 : 1 and the standard Type 3 gearbox the top gear road speed
was around 19.8 mph/1000 rpm.
|
My Ghia runs close to 20mph per thousand.
|
|
|
Craig S
A.k.a.: Craig
Wolfsburg Wizard
Posts: 635
Threads: 83
Registered: May 26th, 2008
Member Is Offline
Location: Sunny Western Sydney
Theme: UltimaBB Pro Blue ( Default )
Mood: In the mood for change
|
| posted on June 10th, 2015 at 10:28 PM |
|
|
There's heaps of calculators on the interwebs. First one on Google:
http://www.osella.com.au/gear-ratios.htm
You just need to know some of the stats of your car (tyre size, gear ratios, etc)
For the mathematically inclinded you can create a spreadsheet yourself.
From memory Phil had an article in the ClubVW magazine that outlined the formula. Also, Daimo once shared a spreadsheet he had which graphed road
speed at various rpm in each gear.
PM me and I'll send you the one I created.
1969 Beetle - June
1974 L Bug - Gwendolyn
2002 Bora V6 4Motion - Anita
|
|
|
farkengruven
Seriously Crusin Dubber
Posts: 167
Threads: 0
Registered: January 29th, 2006
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on June 11th, 2015 at 02:15 PM |
|
|
What year Type 3?
3.875 or 4.125 ring and pinion?
What tyres radial or crossply?
3.875 running 165 80 r15 tyres - 2560 rpm
4.125 running 165 80 r15 tyres - 2730 rpm
3.875 running 560 15 tyres - 2527 rpm
4.125 running 560 15 tyres - 2690 rpm
2007 T5 TDI Crewvan
2003 Passat
NSU Ro80
1975 Passat TS
1973 L bug
|
|
|
hpnotch
Seriously Crusin Dubber
Posts: 133
Threads: 28
Registered: November 11th, 2012
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on June 11th, 2015 at 07:14 PM |
|
|
Cheers - its a Jan'71 - 4.125 according to the manual.
I'll check the tyre size on the weekend.
I bought this tacho in a run down state through ebay and patched it up to look OK - but I wasn't sure of it's accuracy.
However the tacho is reading somewhere around the 2600/2700 mark @50 mph - so I'm happy to think its operating fine.
Thanks for all the replies.
Just as an aside - and not that I have any desire to get to it - what would be the redline mark on these motors?
| Error |
| Sorry, you must be a registered user in order to download attachments. |
|
|
|
|
