Author |
Message |
petesilcock
Part built GTM
Joined: Wed Apr 15, 2015 4:52 pm Posts: 141 Location: Devon GTM: Libra
|
Front Suspension
|
Wed May 09, 2018 6:44 pm |
|
|
petesilcock
Part built GTM
Joined: Wed Apr 15, 2015 4:52 pm Posts: 141 Location: Devon GTM: Libra
|
Re: Front Suspension
I need to be taught how to do this properly I can click on the photos and see them but they don't seem to display.
1. I have put a 'bottle screw' into the top link to make the camber (and castor) easily adjustable Right and Left threads - loosen the lock nuts and turn the centre.
2. Bought roll bar links and shortened to suit - changed from the rose joint rattle units to OEM type I know rose joints are great for competition but not good for road car
3. Fitted 4lb helper springs - these are coil bound when in use however they stop the springs from escaping from their seats when on full droop The spring seats were lowered by Dave Gallop to get the underside of the car very slightly lower at the front. Before adjustment the flat floor was lifting the car with 15mm rake the wrong way.
4. MGF quick rack fitted and new joints where worn.
Pete
|
Wed May 09, 2018 6:55 pm |
|
|
sanzomat
GTM Nirvana
Joined: Sun Oct 19, 2014 10:10 pm Posts: 1138 Location: Bristol GTM: Spyder
|
Re: Front Suspension
All looks very good. I like the adjustable top wishbone . Did you do that yourself? Presumably enough metal removed so it can be shorter than it was originally to give negative camber. The thread on the top ball joint doesn't protrude far from the nyloc - I've always worked on the rule of two clear turns left showing - I guess they were designed for a plain nut with a tab washer? Might be worth checking the tightness of those from time to time, especially as the paint below them might creep a bit. I like the shorter drop links - any impact on movement ratio (and thus stiffness)? I note you aren't on the stiffest anyway!
|
Wed May 09, 2018 8:10 pm |
|
|
Elansprint
Looking like a GTM
Joined: Sat Mar 12, 2016 7:05 pm Posts: 217
|
Re: Front Suspension
Dave i agree about the nylock but the ball joints i bought have a shorter threaded section but they come with a washer with lock tabs to go under the nut to stop it moving not fitted in photo's. i see the large circular washer under the joint is not peened over to lock it in position although these may have been taken before everything was finished Ian
|
Thu May 10, 2018 8:12 am |
|
|
petesilcock
Part built GTM
Joined: Wed Apr 15, 2015 4:52 pm Posts: 141 Location: Devon GTM: Libra
|
Re: Front Suspension
The pics were during works so not finished Yes I cut the wishbones and fitted the adjusters Could not face shimming Not driven since the links altered
|
Thu May 10, 2018 4:44 pm |
|
|
Matty H
Ready for SVA
Joined: Mon Feb 09, 2009 12:11 pm Posts: 317 GTM: Libra
|
Re: Front Suspension
Could you give me details of the front suspension parts interested in doing this myself. Matty
|
Tue Jul 31, 2018 9:12 pm |
|
|
petesilcock
Part built GTM
Joined: Wed Apr 15, 2015 4:52 pm Posts: 141 Location: Devon GTM: Libra
|
Re: Front Suspension
https://s15.postimg.cc/d1lrvujpn/IMG_1116.jpghttps://s15.postimg.cc/70o2yyzq3/IMG_1115.jpghttps://s15.postimg.cc/rkswxjfi3/IMG_1114.jpgLong threaded bar and locknuts to keep dimension of the wishbone. Screws into backboard to further give dimension of the wishbone Cut off part of the roll bar plate Cut wishbone in position that can be easily accessed. 12mm left right threaded bar with nuts and locknuts Offer up and work out the movement needed -cut out this section of wishbone Weld nuts to wishbone Dismantle holding framework. ----- Get camber and castor checked properly!!!! This can adjust both so may be possible to change the self centering Mine with Ford v6 should be on the road in the next couple of months Just now the good summer is better outside than in the workshop
|
Fri Aug 03, 2018 5:52 pm |
|
|
Matty H
Ready for SVA
Joined: Mon Feb 09, 2009 12:11 pm Posts: 317 GTM: Libra
|
Re: Front Suspension
Struggling to find the threaded adjuster where did you get them from and have you used stainless. Matty
|
Wed Oct 24, 2018 10:25 pm |
|
|
petesilcock
Part built GTM
Joined: Wed Apr 15, 2015 4:52 pm Posts: 141 Location: Devon GTM: Libra
|
Re: Front Suspension
|
Thu Nov 01, 2018 5:52 pm |
|
|
Jaykart1227
On the Road
Joined: Mon Jul 13, 2015 6:32 pm Posts: 502 GTM: Libra
|
Re: Front Suspension
Just a thought chaps....is stainless steel componentry best avoided for safety critical items such as suspension? I’ve always avoided using it for anything like that because I didn’t think it had the tensile strength? Is A 4 grade stainless ok in this respect?
|
Fri Nov 02, 2018 7:50 am |
|
|
sanzomat
GTM Nirvana
Joined: Sun Oct 19, 2014 10:10 pm Posts: 1138 Location: Bristol GTM: Spyder
|
Re: Front Suspension
That link doesn't say what tensile rating the stainless is. You can get high tensile stainless, A4-80, that is similar in strength to 8.8 (but nowhere near 10.9's). Most A4 stainless is A4-70 though. The tensile strength of A4-70 is about 7/8's of 8.8's so not exactly weak but worth thinking about it. What is stronger out of the the original tube and the threaded rod? Where are the stress concentrations? I imagine that fatigue generation would be more likely to lead to failure than the tensile strength of any of the components. I would guess that a system with welded nuts and threaded rods would have a number of places where stresses could concentrate compared to a simple tube.
For camber adjustment I'd say a threaded top joint at the end of the wishbone would be stronger but that wouldn't adjust the caster (and would need to be undone to adjust it).
|
Fri Nov 02, 2018 9:46 am |
|
|
Jaykart1227
On the Road
Joined: Mon Jul 13, 2015 6:32 pm Posts: 502 GTM: Libra
|
Re: Front Suspension
Makes sense Dave thanks. I’ve always avoided stainless in any sort of suspension scenario to be on the safe side but I don’t suppose it’s completely necessary.
I’ve had a couple of conversations with Dave Gallop about an adjustable front wishbone (also z cars), I’ll speak more to Dave when he sets my car up but an adjustable joint at the outboard end would be easiest but, dependant on what static / dynamic castor measures at, two adjustable joints at the inboard end would provide full adjustment.
|
Fri Nov 02, 2018 8:01 pm |
|
|
sidewinder
On the Road
Joined: Wed Aug 11, 2010 9:27 am Posts: 621 Location: Sheffield GTM: Libra
|
Re: Front Suspension
I've had stainless bolts for the front wishbone pivots, lower hub pinch bolt and shock mount for years. I use as an everyday road car which IMO needs be more durable than a track car due to the high shock loading from poor roads unlike super smooth tracks! The issue with making parts out of SS is the welding which can sensitise the SS to stress corrosion cracking (esp if used in a harsh environment) and hot cracking (during cooling) due to low melt impurities in the metal. Both of these can be offset by good quality material (inc the weld filler material) with proper compositions and good welding technique.
_________________ 2000 GTM Libra 1.8VVC 145BHP
|
Sat Nov 03, 2018 11:42 am |
|
|
sanzomat
GTM Nirvana
Joined: Sun Oct 19, 2014 10:10 pm Posts: 1138 Location: Bristol GTM: Spyder
|
Re: Front Suspension
sidewinder wrote: good welding technique. I'd better not use stainless then
|
Sat Nov 03, 2018 10:41 pm |
|
|
petesilcock
Part built GTM
Joined: Wed Apr 15, 2015 4:52 pm Posts: 141 Location: Devon GTM: Libra
|
Re: Front Suspension
I think the point is being missed
The top wishbone is a thin walled tube - wall thickness less than 1mm of mild steel Compared to a 12mm bolt the tube will fail. Cross section area is around double for the threaded bar compared to the wishbone tube Correct ref. welding - must be Tig by someone who knows what they are doing The stress on the wishbone is not great unless you clobber a curb at speed I would suggest after doing that a check would be needed anyway
|
Tue Nov 06, 2018 5:37 pm |
|
|