I'm tearing down my entire suspension and replacing all the worn parts.

This is going to be a daily driver with a fuel injected 2270. I'm wallowing through the myriad of suspension parts on the various websites, and it is befuddling. It seems I could spend between $500 and $5000 and I'm not sure how much better it would be.

I would like to return the car to factory specs (or maybe a little better), but I don't want to spend $$$ building a suspension for the racetrack.

Any suggestions for tie rods, ball joints, bushings, torsion bars, front shocks (or inserts), rear springs, rear shocks and anything else I'm forgetting.

Thanks.

George

What year is your car? That makes a difference with the ball joints. Turbo inner and outer tie rods are more direct due to their design and are a great addition to the steering feel and performance. Bilstein shocks and strut inserts make for a great ride with even better control. Make sure to inspect the bushings all around as too much deflection will compromise the handling and can prematurely wear other components. You're dealing with a 50yr old car and these parts need an upgrade!

General guidance:

Avoid Urethane bushings, poly bronze bushings, or any sort of bearing/spherical bushing for street use. They have serious drawbacks for street use. All major OEM's use rubber bushings for sound engineering reasons I won't go into here.

The bottom line, rubber is a great compromise for keeping good ride quality and you can still get amazing handling too without the need for "race track" solutions on a street car.

Coilover solutions - for most, this is overkill on a street car. This is where costs increase exponentially - cha ching! No need to go there for the average street car.


Here's my personal recipe:

Torsion bars - Replace front torsion bars if there is any hint of pitting corrosion on them or wear marks from having contacted the inside of the LCA. Sway-A-way replacements available from PMB. I went stock size. Avoid the urge to think more is better unless you already understand supsension tuning, know what you want, and are prepared to buy more tuning parts later. Even it they aren't corroded and are OEM, I'd still probably replace them simply because torsion bars have lifecycle limits. Without knowing exact mileage and prior use, better safe than sorry but I do understand budget constraints too.

Front LCA bushings - Elephant Racing due to OEM fit to the LCA's and OEM bushing durometer. They come with install tools and great install direction, I had zero issues installing these. As previously stated, worn bushings will lead to premature wear on the torsion bars.

Ball joints - Lemforder for Front LCA's for me.

Front Struts: Replace them with something quality, Boge, Bilstein, Koni. Dampers do wear out and cannot be tested with hand force. The 914 Bilstein front struts (inverted damper) are a nice upgrade but at this point in their life, be prepared to replace not only the strut cartridge but also the bronze linear bearings in the strut body and the seals -- this gets pricey fast. I went Boge gas strut but I'm working on refreshing a set of the 914 Bilstein struts in the background for future tuning.

Steering: Lemforder turbo tie rods. Be warned - although they do have a more direct road feel, and increased front end responsiveness, this isn't a once size fits all solution for everyone. They increase NVH (road noise, and vibration in the steering wheel) for the gain in responsiveness. OEM steering with renewed inner joint bushings (914Rubber) and standard tie rod ends are still very responsive compared to your average car. Don't forget to check the bearings in both the steering column and down on the input shaft to the rack & pinion where it passes though the bulkhead. Replace those if they are worn, contaminated with dirt, etc.

Rear Semi-Trailing Arms:

I used Restoration design bushings. They offer both OEM durometer and a stiffer 85 shore version. I went with 85 shore for my own tuning reasons that I won't try to outline here. I'd recommend most people go for the street version. The RD version is cheaper than the Elephant racing version. I went with RD because I wanted to re-use the hollow OEM rear pivot shafts and don't want the added weight of other suppliers solid stainless steel pivot shaft solution. Not knocking them, just wasn't for me.

Rear Springs
I'm starting at 100 lbs/inch 914Rubber springs and will tune from there accordingly.

Rear Dampers - Replace them. Dampers do wear out over time and cannot be tested reliably with hand force. You also want nice fresh, compliant bushings in the bottom of the rear dampers that will come with new parts. 25 year old, hardened bushings aren't doing you any favors w.r.t. ride and NVH. I'm partial to the Bilstein's with the provision for some rear ride height adjustability.

Anti-roll bars (ARB) are nice (I have stock both front and rear and will tune from there as the starting point). However, my 1st 914 had no ARB's - quite honestly it was fine for Michigan's largely straight roads. I eventually got that to a point I liked for occasional autocross and spirited cornering by tuning just front and rear spring rates.

Refresh it once now, and you'll enjoy many trouble free miles. That is my philosophy and I'm sticking with it!

Thank you so very much. You have provided exactly what I'm looking to figure out.

I just got done disassembling my front and rear suspension. The only thing left to do is remove the rear wheel bearings and front races. That took a couple of days and some long nights with hammers, map gas, PB Blaster, breaker bars and a bit of ingenuity.

Every wearable part is worn out!!!!

(Except for the brake rotors for some weird reason).

Now I have to clean, media blast, powder coat, zinc plate and order some parts.

Thanks for such a complete write up. I will definitely use your suggestions.

George

i did pretty much what @Superhawk996 is saying to do. all in one hit.

only thing i did not change were the rear springs.

the car feels fantastic.

Bilsteins are my preferred. Front and back. Try replacing the rubber and stock bits 1st. Turbo tie rods will stiffen up the response, and let you feel the road more. Do the ball joints too.
In the back the 100# springs will accommodate daily driving and improve the ride. The stock springs were 66-68#. We do also have a 140-160# progressive spring, but if you want a more “stockish” ride, I’d stick with the 100#. We just did our 6th run of these, and they’re in stock ready to ship now. Made right here in the good ole USA

https://914rubber.com/100-lb-sport-rear-spring-set



Mark

All good stuff right here!

Looks like Bilstein offers the B6 Front and Rear shocks for the 914.

https://www.bilstein.com/us/en/product-sear...798046438879637

https://www.bilstein.com/us/en/product-sear...798046438879637

I'll probably go with these.

George

factory boge sachs shocks, factory height springs, bushings should be just fine

I run the B6 on mine. We did build our springs to the factory height, if you are going to replace the springs the 100# would be my recommendation.

I noticed a marked improvement in handling and feel. This was on my stock 1.7. I need to do my 2.0 as soon as I get more metal work done.

At $135 a set (the springs) they may be one of the least expensive parts you replace

Superhawk nailed it. The only addition I'd add is to replace the front strut upper mount rubber. As Superhawk stated, unless it's been touched recently the rubber in the upper mount rubber is 50 years old.

There is a huge temptation to upgrade this and that with the suspension and it's definitely a slippery slope. Personally, for the street, I think everything stock is still an incredibly responsive ride compared to todays vehicles. With suspension 'upgrades' you run the risk of making the vehicle a tad too aggressive for street driving.

@Superhawk996
When I did the build on my 996, I did a monoball conversion on everything but the upper strut/shock mounts. On those upper mounts I filled in the voids with 3M urethane to firm them up a bit.
I know every chassis is different, but it seems to have worked out incredibly well on that car. I only get a bit more high freq road noise on particularly grainy pavement, meanwhile the handling is phenomenal in so many ways.

Without pushing you to the point of charging me a consulting fee, is there any reason I should expect a different result from the same approach on the 914?

Thanks,
Van

Having done 2 914's full suspension.....it will be the best money spent next to horespower or engine.

with that said it won't be cheap. If you do the work yourself avout 3 to 4 K. Progressive shocks and springs are money well spent.

@Van B
Modern bushings tend to be much larger OD to allow for packaging of isolation (in void direction) and still being able to provide the appropriate rate in the solid direction to have responsive handling.

You won't find voided suspension bushings on the 914. I'm sure there may be an exception out from some supplier there but rear trailing arms are solid, front LCA's are solid, Rear Dampers are solid (top & bottom) as are the strut tops.

The simple fact is that the 914 bushing are pretty small by modern standards and really don't have the suspension package space to fit in voids.

The rear trans mounts are voided by the way. Same for the 914/6 front engine mount.

Everything is a compromise as you've noticed.

I need to add to my list of To Do Items

Thanks. After re-reading my post, I wish I'd expanded a bit more. Specifically what I was thinking of was going with spherical for the control arms but retaining the rubber top mount for NVH.
The trouble with the voids, even on modern cars is that they allow a noticeable toe and caster change when you increase your grip enough to allow for harder acceleration or braking.
I learned a lot on that build and among them is that the thing I don't envy about your job is that you live in a world where endless compromise is required. And if you aren't able to pick a direction you end up with an enduro motorcycle i.e. sucks on the track and on the street lol!

Van

@Van B
I have to say, that at the level (grip/braking/cornering) you're playing at, those are attribute tradeoffs that only you can make. Hat's off to you for pursuing what suits you. that is what tuning is all about.

Personally, I would never do Spherical and/or Heim Joints on a street car which is where the OP question originated.

By the time that you're truly suffering from the symptoms you noted, you're playing in, or on, the edge of an operational envelope that 98-99.9% of the population will never experience on public roads and/or doesn't have the driving skill to achieve.

I say that in no way to shame you or portray your driving in a negative way. I say that having run BFG R1 Autocross rubber on my Miata as my daily driving rubber in the summers. That was done on OEM bushings with non OEM alignment. I could get away with absolutely absurd braking and cornering limits that scared the out of anyone not aware that the car was capable of it. Yes, it could have been better with Spherical Bearings in the LCA's & UCA's but the % improvement wouldn't have been meaningful to me for street use.

The increased road noise, suspension harshness over broken pavement wouldn't have been worth it to me. Not to mention wear and maintenance for a street car.

The end point being, its easy for people to read a thread like this and get the idea that they are missing out on something by not going to Urethane, Poly-Bronze, or Spherical bearings at the most extreme. Trust me, for 90+% of us, you not missing anything for street use. When you find that you're truly missing out, you'll know it, and then you can make the attribute trade offs for yourself.

ECS Tuning has LCA ball joints for $160, $63, $45 and $40.

Is there really any difference? Lemforder are $63.

Thanks.

George

Great Post!!

One more vote for Superhawk's excellent advice, and suspect something like this is not only great for a street car but also most 914s…even those used for occasional sports purposes.

Only deviation I would make, having done Bilstein HDs last time around, is Koni reds (new or rebuilt if NLA). Ride is a very personal thing, but in my view softer Konis are nicer than softer Bilsteins. I find the Bilsteins ride great over 50~ mph, but make for a "busy" ride up 50~ mph—which is a lot of the time on a good curvy road, and just when need compliance most. YMMV.

Thanks to the OP for initiating, and certainly to all contributors in this thread. Just great information provided for those of us who can use it.

As another (evolving) setup, and having redone my five-lug suspension twice over 30 years—first when the car was a four, and then as a six—here's where I'm going for a "mildly modded," narrow-body street 914 with an emphasis on compliance and feel vs ultimate grip. I think…

Wheels: Fuchs 15x6
Tires: 185/70R15 Avon CR6ZZ (current) or 215/60R15 Avon CR6ZZ rear (or possibly all around)
Dampers: KW V3 (come with new raised spindles, sounds like they ride beautifully; 911 front struts available, custom rears would be needed)
Springs: New and soft front torsion bars, 140-150lb rears
ARB: 22mm Weltmeister front with custom drop links (done), no rear (been rethinking this lately)
Bushings: Stock-style Elephant rubber in new A-arms and rebuilt trailing arms (done)
Steering: Turbo tie rods, rebuilt rack, rebuilt column

Current brakes are PMB Alfa calipers up front with rebuilt 914 rears, but KW struts & SirAndy's feedback mean I'll probably move to 986 2.5 calipers all around.