Printable Version | Subscribe | Add to Favourites
New Topic New Poll New Reply
Author: Subject: Can I do this ?
slopecombat

posted on 18/5/07 at 10:16 PM Reply With Quote
Can I do this ?

I've got a pair of SAAB 900 uprights. They look similar to Cortina ones except for the position of the arm that links with the steering bar.

In the Cortina's ones is in the front and in the SAAB ones is in the rear.

Can I rotate the uprights ?




regards,

Modesto

View User's Profile Visit User's Homepage View All Posts By User U2U Member
BenB

posted on 18/5/07 at 10:37 PM Reply With Quote
As long as the kingpin inclination angle isn't FUBARd it should be fine.....
View User's Profile Visit User's Homepage View All Posts By User U2U Member
scoop

posted on 18/5/07 at 10:50 PM Reply With Quote
FUBARD.... IVE ALWAYS LOVED THAT
View User's Profile E-Mail User View All Posts By User U2U Member
Bob C

posted on 18/5/07 at 10:59 PM Reply With Quote
Find out what you can about "ackerman" then decide...
If you do it you probably won't be able to design out the resulting tyre scrub when cornering . . . . but some folk actually reckon that's a good thing!!
cheers
Bob

View User's Profile Visit User's Homepage View All Posts By User U2U Member
12a RX-7

posted on 18/5/07 at 11:20 PM Reply With Quote
can you not fit a rear steer rack and make sure your engine is nice and far back to clear it ... or notch the sump to clear the rack.

some production cars run anti ackerman and allsorts of odd combinations .... they do spend a large fortune of money deciding on these things though.

View User's Profile Visit User's Homepage View All Posts By User U2U Member
BenB

posted on 19/5/07 at 07:12 AM Reply With Quote
King pin inclincation (KPI) = Ackerman
View User's Profile Visit User's Homepage View All Posts By User U2U Member
flak monkey

posted on 19/5/07 at 08:26 AM Reply With Quote
quote:
Originally posted by BenB
King pin inclincation (KPI) = Ackerman


Umm, no, not really.

KPI is the angle between the upper and lower balljoint from vertical with zero camber. (NOT camber). KPI helps with self centreing.

Ackerman is essentially to do with the angle of the steering arm from the upper ball joint when the wheels are pointing straight ahead. You can have positive and negative ackerman. It results in one wheel turning slightly more than the other in cornering.

Those arent the best descriptions, but I cant be bothered/dont have time to do a doodle at the moment.

David





Sera

http://www.motosera.com

View User's Profile Visit User's Homepage View All Posts By User U2U Member
dilley

posted on 19/5/07 at 09:12 AM Reply With Quote
flak where do you get your avatars from??
View User's Profile E-Mail User View All Posts By User U2U Member
MikeR

posted on 19/5/07 at 09:44 AM Reply With Quote
hi g/f poses for him !!!


View User's Profile View All Posts By User U2U Member
flak monkey

posted on 19/5/07 at 10:30 AM Reply With Quote
quote:
Originally posted by MikeR
hi g/f poses for him !!!




Yeah right

Thats Apena - google it with safe search turned off... Some more in my archive





Sera

http://www.motosera.com

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Doug68

posted on 19/5/07 at 06:20 PM Reply With Quote
I don't see that there's going to be any issues doing this.
The KPI will remain the same when swapped from one side to the other and the right castor - camber is a function of the wishbone design.

Look at this for the Ackermann definition.

This is good introductory reading too.

The importance of Ackermann appears to be minimal at anything other than slow speeds where tyre scrub is an issue due to the big steering angles that occur then.

View User's Profile Visit User's Homepage View All Posts By User U2U Member
slopecombat

posted on 19/5/07 at 11:17 PM Reply With Quote
Then ...

I think it will be better if I don't contradict Mr. Ackerman, Mr. Toe, Mr. Camber & Mr. Castor.
I'm not sure if this configuration will displease Mr Disk Brake too.

I'll follow Mr. Saab design.

Thanks.

Modesto

View User's Profile Visit User's Homepage View All Posts By User U2U Member
MikeRJ

posted on 20/5/07 at 12:05 AM Reply With Quote
quote:
Originally posted by Doug68
The importance of Ackermann appears to be minimal at anything other than slow speeds where tyre scrub is an issue due to the big steering angles that occur then.


The problem with turning rear steer hubs around to get front steer is that you get anti-ackerman geomtery, i.e. the inside wheel will turn less than the outside one. This can't be conducive to good road manners...

[Edited on 20/5/07 by MikeRJ]

View User's Profile View All Posts By User U2U Member
Doug68

posted on 20/5/07 at 04:49 AM Reply With Quote
True.
View User's Profile Visit User's Homepage View All Posts By User U2U Member
rusty nuts

posted on 20/5/07 at 07:50 AM Reply With Quote
The Saab 900 was FWD doesn't look like a FWD hub assembly to me
View User's Profile View All Posts By User U2U Member
slopecombat

posted on 21/5/07 at 08:55 AM Reply With Quote
SAAB 900 90's



cheers

Modesto

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Peteff

posted on 21/5/07 at 09:11 AM Reply With Quote
I'd give it a try.

With the cv joint cut down it looks like a good alternative and it looks to have an angle built in the wrong way round. Rescued attachment saab.jpg
Rescued attachment saab.jpg






yours, Pete

I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.

View User's Profile View All Posts By User U2U Member
rusty nuts

posted on 21/5/07 at 04:54 PM Reply With Quote
From that angle it's plain that it's FWD
View User's Profile View All Posts By User U2U Member
t.j.

posted on 21/5/07 at 08:20 PM Reply With Quote
hmmm,

Not sure about it.
- there is probable an angle (castor) static in the upright which has to be compensated.
- watch out where you're rod ends come.
They are tapered! Otherwise your rack comes high mounted.

View User's Profile View All Posts By User U2U Member

New Topic New Poll New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.