Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

VH rpm at 100kmh

Joined
Jun 24, 2005
Messages
233
Reaction score
0
Points
16
Age
44
Location
Wollongong
Members Ride
VH SL Wagon
I have a GU6 diff in my VH wagon which is a 3.36 Small Salisbury
at 100kmh i'm at 3150rpm and at 110kmh im at 3500rpm
M21 4 speed, 253 V8
from a diff calc looks as though its 3.9 ratio, I though small salisbury diff went 3.36, 3.55, 4.44
must be a faulty tacho i think
 

SL/ENUT

The SL/E Fanatic!
Joined
May 28, 2004
Messages
2,086
Reaction score
148
Points
63
Age
41
Location
Burnie, Tasmania
Members Ride
VB SL/E 5L
Going though my commodore records stuff, GU6 was never fitted to a Commodore, never a Holden option.
My understanding is the following
GU4 3.08:1 on both ten bolt and 8 bolt Sals diffs
GV4 3.36:1 on both same diffs
GU7 2.78:1 on 8 bolt diffs
GU8 3.90:1 on 8 bolt diffs(common on the Starfire 4 powered ones)
GV7 3.55:1 only ten bolt diff
G70 2.60:1 only a ten bolt diff

4.44:1 is a ten bolt only diff, used only in the one tonner cab chassis-HQ-WB
 
Joined
Jun 24, 2005
Messages
233
Reaction score
0
Points
16
Age
44
Location
Wollongong
Members Ride
VH SL Wagon
i meant GU4, maybe its got a starfire diff, i'll have to jack it up and check the rotation
 
Joined
Jun 24, 2005
Messages
233
Reaction score
0
Points
16
Age
44
Location
Wollongong
Members Ride
VH SL Wagon
sorry GV4 i just looked at the vin plate
 

Guzzoline addict

New Member
Joined
Aug 31, 2009
Messages
201
Reaction score
3
Points
0
Members Ride
vr v6
The speedo or tacho might be out,have you got a Automotive Multimeter and some sort of gps to check?. Also what code for the engine is on the vin?, if it was a 6 check if the tacho has been switched.
 
Joined
Jun 24, 2005
Messages
233
Reaction score
0
Points
16
Age
44
Location
Wollongong
Members Ride
VH SL Wagon
the car was a 2.85l 6 with a vacuum gauge, the dash was out of a VH V8 but that was already fitted when i bought it. I do have a multi meter with tach and gps on my phone so i can double check next time.
 
Joined
Jun 24, 2005
Messages
233
Reaction score
0
Points
16
Age
44
Location
Wollongong
Members Ride
VH SL Wagon
i don't have access to the car yet pick it up friday however i did some googling and the speedo drive gear is a light blue 24 or 25 tooth which is meant for a 3.9 ratio, the speedo reads true so i'm thinking it has a 3.9 ratio fitted, i will double check though. i will end up with a VL 3.45 BW later after i can find one local, already found a VS diff with disks but will fit these to the VL diff once i find one.
 

Tree cutter

Tree cutter
Joined
Apr 15, 2006
Messages
1,020
Reaction score
9
Points
38
Location
Mt Gambier SA
Members Ride
VX Calais SuperchargedV6
Those revs sound right for a 3.36 diff and 14 inch wheels. My old HT Kingswood used to sit on 3500RPM at 70MPH with a 3.36 diff.
 
Joined
Jun 24, 2005
Messages
233
Reaction score
0
Points
16
Age
44
Location
Wollongong
Members Ride
VH SL Wagon
picked the car up today, got it to 110km on the gps (dash is spot on) and its was revving at 4100rpm and at 100kmh it was about 3700rpm... i can drive everywhere in 4th gear its almost as bad as the old 2.6 diffs that could do 120kmh in 1st gear.
i'm pretty sure its a 3.9 ratio but i will remove the cap and change the oil and check soon
 
Top