Suspension Refresh

For you flat four Porsche 912 fanatics

Moderators: Miggs, KS

GonzoBard
DDK addict
Posts: 114
Joined: Sat Feb 28, 2015 11:38 pm

Suspension Refresh

Post by GonzoBard »

I’m planning to remove the suspension from my ‘66 car over the coming Winter and have components powder coated / fixings plated etc. New rear dampers are needed but I wondered what upgrades / changes I might consider. What might others recommend? I’m generally happy with the ride, i.e. I’m not necessarily looking to firm it up, nor am I looking to lower it to ‘improve’ the stance. Any suggestions welcomed. Thanks.
User avatar
hot66
Moderator
Posts: 18378
Joined: Tue Nov 11, 2003 4:17 pm
Location: North Yorkshire

Re: Suspension Refresh

Post by hot66 »

best thing you caan do is have a proper alignment and corner weight set up once youve finished the build up. A nice compliant and predictable handling set up IMHO should be the aim.

I'm not upto date on swb suspension recomendations these days , but there is so much work on the swb race cars and rally cars some of this should have trickled down to a great fast roads set up.
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster

Its not how fast you go, but how you go fast ;)
GonzoBard
DDK addict
Posts: 114
Joined: Sat Feb 28, 2015 11:38 pm

Re: Suspension Refresh

Post by GonzoBard »

Funnily enough I was watching the Fordwater Trophy on YT this morning for the early 911s - their handling looked pretty good! Thanks
Ollie
I luv DDK!
Posts: 755
Joined: Wed Jun 15, 2005 10:17 am
Location: St. Leonards-on-Sea

Re: Suspension Refresh

Post by Ollie »

Suggest some adjustable rear spring plates to make ride height and alignment easier.

https://www.rsrproducts.com/product-pag ... r-adjuster
Hannibales
DDK Fanatic
Posts: 98
Joined: Fri Jul 31, 2015 5:48 pm
Location: Cheshire

Re: Suspension Refresh

Post by Hannibales »

Split bolts for the trailing arms if you haven't got them already make future removal and adjustments much easier as you don't have to drop the transmission. If you don't have them already then just cut through the old ones with a hacksaw and replace on reassembly.

Elephant Racing do some nice parts that can tighten up the feel without being harsh. I have their stock ride rubber bushes all round and am very happy with them. As a note, all the early 911s at Goodwood were running stock suspension so there's no need to go crazy by any means.
Oli

1966 912 now with '69 911E 2.0 MFI
1989 944 S2
2009 Boxster S Sport Edition
1998 Land Rover Defender Wolf
1955 Daimler Ferret Mk1
GonzoBard
DDK addict
Posts: 114
Joined: Sat Feb 28, 2015 11:38 pm

Re: Suspension Refresh

Post by GonzoBard »

Thanks gents, very useful.
GonzoBard
DDK addict
Posts: 114
Joined: Sat Feb 28, 2015 11:38 pm

Re: Suspension Refresh

Post by GonzoBard »

So new Koni rear dampers have arrived, look straight forward to fit. I’ll start by rebuilding the front suspension, then move to the rear, which looks to be more involved. The Elephant Racing bushes look good so I plan to use those.
Sam
Nurse, I think I need some assistance
Posts: 4098
Joined: Fri Jul 02, 2010 8:56 am
Location: Cambridge

Re: Suspension Refresh

Post by Sam »

Try to get a ride in an elephanted car. I’ve been in a couple that have been really hard riding, though it was a while ago and I think they probably had more than just bushes. I do very much remembering resolving at the time that standard was the answer.
964 C2 Targa. 205 1.6 GTi. Testarossa. Fisher Fury Fireblade. Motorhome. Motorbikes. Scooters. Pushbikes. Threadbare Saucony Peregrines. Dog. Human relations and friends. 97.5%-built house.
User avatar
hot66
Moderator
Posts: 18378
Joined: Tue Nov 11, 2003 4:17 pm
Location: North Yorkshire

Re: Suspension Refresh

Post by hot66 »

I’ve had polybronze er. Bushes since about 2010 and find them great
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster

Its not how fast you go, but how you go fast ;)
911hillclimber
Nurse, I think I need some assistance
Posts: 19155
Joined: Mon Mar 10, 2008 6:26 pm
Location: West Midlands

Re: Suspension Refresh

Post by 911hillclimber »

Just my 2 pence;
I have a 73T.
Rear suspension mods are simple and are
Poly bushes fitted in 1989 and are still in the aluminium arms, never been touched since 1989. 70K miles ans 13 years road hillclimbing.
Rear torsion bars are from a 3 litre Turbo, can't recall the diameter, but larger than the T's. I would keep your current rear torsion bars.
Split spring arms to aid ride height and corner weighting. Accurate corner weighting really helps the 911.
Koni adjust able dampers set 1/2 way in the damping adjuster range.

In all this i feel the alignment quality will make a bigger difference than many mods and of course the tyres.
The front is stock except for the Bilstien fixed rate dampers set by Bob Watson in 1992.

The front did have ball bearing top mounts, poly bushes etc but now all stock (new) rubber.
Did not notice any difference from all the solid pivots to rubber bushes except quieter.

Steering rack is stock with turbo track rod arms.
Anti roll bars are 2.7 RS spec. which required mounts to be welded to the rear shell and front arms as per factory.

Momo steering wheel, 13" makes speed driving nice, parking heavy but worth it.

If a simple road car is your direction I would go stock parts all in perfect condition, alignment done by an early 911 specialist and nice correct sized tyres for the rims.

Just my take on my 33 years with the car.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
SeanP
I luv DDK!
Posts: 776
Joined: Thu Sep 06, 2012 11:59 pm
Location: North West Essex

Re: Suspension Refresh

Post by SeanP »

Be aware that SWB front suspension is very different to LWB suspension. You cannot use LWB turbo tie rods on a SWB rack. You find that the SWB rack is shorter than a LWB rack and you will run out of adjustment before you get it aligned. There is a work around using Rover 214 tie rods.
Also the bushes on the A arms are different along with the ball joints.
Be careful using stiffer torsion bars as a 912 is lighter than a 911. What works in a 911 might not work in a 912
1966 912
1969 912/6 hotish rod in build
1974 914 Dead
LI 125 Lambretta (Yeah right it’s a 125)
Mini Cooper s
GonzoBard
DDK addict
Posts: 114
Joined: Sat Feb 28, 2015 11:38 pm

Re: Suspension Refresh

Post by GonzoBard »

Thanks gents. I hadn’t planned on changing torsion bars. I had noted that all the solid tie-bars I had seen were for LWB cars, rather than SWB cars, so may choose to stick with what I have. I’m aiming for a well-handling road car, so not really aiming for anything much over OEM. The ER a-arm bushes appeared to be a better design than others, but then realised it was LWB bushes I was looking at, the SWB bushes are different. Interestingly I recently removed the steering wheel that came with the car twenty years ago to find it was a 914 wheel. I replaced it with a wheel in better condition, only subsequently to realise it was a larger, original spec wheel (400 or 420mm, can’t remember which). Funnily enough I much prefer the original spec wheel! Not cool, I realise, but hey.
GonzoBard
DDK addict
Posts: 114
Joined: Sat Feb 28, 2015 11:38 pm

Re: Suspension Refresh

Post by GonzoBard »

On the tie rods Sean, are you replacing the Porsche tie rod ball joint with the Rover ball joint? The Rover ball joint looks to have a longer threaded section?
SeanP
I luv DDK!
Posts: 776
Joined: Thu Sep 06, 2012 11:59 pm
Location: North West Essex

Re: Suspension Refresh

Post by SeanP »

GonzoBard wrote: Fri Dec 15, 2023 10:42 am On the tie rods Sean, are you replacing the Porsche tie rod ball joint with the Rover ball joint? The Rover ball joint looks to have a longer threaded section?
Yes Rover tie rod porsche ball joint. Last time I looked the Rover tie rods were £14 each.
You could buy a pair from elephant racing if you feel flush!
1966 912
1969 912/6 hotish rod in build
1974 914 Dead
LI 125 Lambretta (Yeah right it’s a 125)
Mini Cooper s
GonzoBard
DDK addict
Posts: 114
Joined: Sat Feb 28, 2015 11:38 pm

Re: Suspension Refresh

Post by GonzoBard »

Thanks. See what you mean about flush ER tie rods.
Post Reply