FE-FC Holden Discussion Forum
May 22, 2024, 04:24:24 AM
Welcome,
Guest
. Please
login
or
register
.
1 Hour
1 Day
1 Week
1 Month
Forever
Login with username, password and session length
News
: The FE-FC Holden Car Club of NSW are proud to host the
19th FE-FC Holden Nationals
. Check out the
announcement video
for more.
Home
Help
Search
Calendar
Login
Register
FE-FC Holden Discussion Forum
>
Technical Board
>
Modification Help
(Moderators:
RET
,
Glenn 'Stinky' Stankevicius
,
gp
) >
Diff Ratio
Pages: [
1
]
Go Down
« previous
next »
Add bookmark
|
Print
Author
Topic: Diff Ratio (Read 3985 times)
fcwrangler
nsw-club
Guru
Offline
Model: FC
Posts: 1257
JIM-- Gilead NSW
Diff Ratio
«
on:
August 05, 2018, 10:58:41 AM »
0
I’m putting the front and rear ends together for the FC and just wanted suggestions on what diff centre to fit. The car will be running a warm grey with triple strommies, headers, mild cam and 2” exhaust with standard gearbox and EJ front and rear ends. It will be rolling on 15x7 mags with either 205 or 215 tyres. I have the standard diff as well as a 3.55 and a 3.36. Will be used mostly for cruising suburbs and highways.
Thanks in advance,
Jim
Logged
on the seventh day: God Made Holden
Errol62
Guru
Offline
Posts: 1150
Re: Diff Ratio
«
Reply #1 on:
August 05, 2018, 11:12:59 AM »
0
Knowing the aspect ratio of the tyres would help but with 17” rims 3.55:1 would be safe.
Sent from my iPhone using Tapatalk
Logged
mcl1959
vic-club
Guru
Offline
Posts: 6155
FE's rule
Re: Diff Ratio
«
Reply #2 on:
August 05, 2018, 12:22:19 PM »
0
I agree, 3.55 would be the best in my opinion
Ken
Logged
ardiesse
nsw-club
Guru
Offline
Model: FC
Posts: 1299
Re: Diff Ratio
«
Reply #3 on:
August 05, 2018, 09:22:37 PM »
+1
Jim,
I'm with Ken. 3.55 would be the starting point. Mild cam and triples suggest your car would need a bit of a prod to get away cleanly from a standing start. Hmm. Compare the diameter of the rear tyres you're thinking of fitting against an original 13" crossply. If your new tyres stand taller, then you could go 3.89, and change up a ratio if the car feels too low-geared.
Or if you're doing a lot of freeway driving and not much stop-start, then 3.36.
Weight is the enemy. Resist the temptation to load the car up with accessories. It might be instructive to compare the weight of your new wheel/tyre combination against standard. I know, it sounds odd. Recently I changed tyres on my commuter pushie, and it just felt . . . slow. My new tyres were about 80 g heavier (each) than the old ones. But that's how it works with wheels and tyres. You are storing energy in rotation as well as plain old linear motion, and the effective inertia is twice the tyre's mass. Imagine a runner lining up for a race in steel-cap work boots . . .
Rob
Logged
Remember: if your Holden's not leaking oil, it doesn't have any.
fcwrangler
nsw-club
Guru
Offline
Model: FC
Posts: 1257
JIM-- Gilead NSW
Re: Diff Ratio
«
Reply #4 on:
August 06, 2018, 08:36:16 PM »
0
Thanks guy’s I’m cleaning up the 3.55 diff as well as putting new bearings and seals on the axels. Also in the process of overhauling the front cross member with new bushes, seals and rubbers.
Jim
Logged
on the seventh day: God Made Holden
Pages: [
1
]
Go Up
Add bookmark
|
Print
« previous
next »
Share this topic...
In a forum (BBCode)
[url=http://forum.fefcholden.club/index.php?topic=27193.0]Diff Ratio[/url]
In a site/blog (HTML)
Diff Ratio
Jump to:
Please select a destination:
-----------------------------
General
-----------------------------
=> General Board
=> FE-FC Holden Nationals
===> 2020 - Wangaratta - 18th FE-FC Holden Nationals
===> 2012 - Perth - 14th FE-FC Nationals
=> Events, Shows etc
-----------------------------
Technical Board
-----------------------------
=> Restoration Help
=> Modification Help
=> General Technical
-----------------------------
Galleries
-----------------------------
=> Members' FEs and FCs
===> Members' Other Vehicles
=> Project Cars - FEs and FCs Under Construction
===> Members' Other Vehicles Under Construction
=> Members' Completed FE-FC Projects
===> Completed Projects - Other Vehicles
=> Unreal Cars - Members' Artwork
=> Little Cars - Members' Model FEs and FCs
=> Original Advertisements, Brochures
=> Other Images
-----------------------------
For Sale and Wanted
-----------------------------
=> Cars For Sale
=> Cars Wanted
=> Parts For Sale
=> Reproduction Parts
=> Parts Wanted
=> Other Stuff For Sale
=> Other Stuff Wanted
=> Auction and Trade Links
Loading...