happy to have had the bars on for a few days, this is a prototype bar that's not final, but very promising

 

Will the bars work on SPASM cars?
I would not mind a rear adjustable bar.

 

What problem are we trying to solve?

 

Oversteer.
I think the rear bar might be too stiff.

 

Seems more of a veiled 'sales' thread. Two posts by the original poster and both are for something for us to buy.

 

Gem is a good guy. He frequently tracks the car hard, and (along with others) has found there isn't a lot of good, accurate experience/knowledge with the 991 platform for that kind of use. So we've been methodically working through a few different items and setups to get him to where he needs to be, and some of those items and services have been test items while he is the guinea pig most weekends at the track--the results are becoming positive, which means ourselves and other companies are able to offer products that are tried-and-true improvements over stock for people who are driving beyond the original components, which is a win for everyone.

Sam

 

Any feedback on these bars? Just bought a base suspension car and am looking for an upgrade path non-PASM.

 

hmmm. yes a update is overdue here..non PASM, thats interesting, and not sure if its been done, using this setup. I dont want to ruffle any feathers here but will be candid, as promised on my feedback.

I had a similar situation, but my car is PASM; just not PASM-Sport, which sits 10mm lower and is stiffer too.

so here is my update and kinda my reply to your post above

... so not sure how this translates to a non-pasm car; ramping up the coil rate on a damper that you can't turn up the compression and rebound on is different that what I did, and fwiw, I need the PASM bit of it so the damper can keep up with a more stout coil rate. It may be fine on the other hand , but I think the KW kit is for PASM only cars; i'm pretty happy with my results.

I run a tarret camber hat I'm very content with, its made for oe coils and fits a 70mm spring seat, avail for other fitting sizes as well iirc, aso can get in 60mm or 2.5" perhaps?

When I first replaced the coils with KW H.a.s. kit, the oe non sport PASM sways were clearly not up to the task, so I tried the GT3/Tarret rear test bar setup, with mixed results, hence the quiet thread... I have been meaning to do a new thread and will now, soon showcasing the new product.

I felt the GT3 front bar off a 991gt3 isnt a good fit for a non gt3-991,just my opinion so take that fwiw for me, the drop link geometry just didnt articulate enough/have correct angles etc up front, which was a OE part when fitted to a non gt3 991; so testing the rear bar became kinda a moot point.

GT3 links are much longer and thats why the gt3 bar works there, they shot us in foot in the design on non 991gt3 and gave us much shorter drop links. idk why. cost savings or to ensure you ante up the cash for the right car if you really wanna dedicate to track use. But this is a solution thast working for me tracking my 991s, 'better' body control/less overall yaw and lean than with the softer springs for sure which is more confident, I havent yet gotten enough data to publish lap time findings, but will when I can.

Unless you run an aftermarket damper you cant use the tarret adapter that clamps to shock body and allows usage of a taller drop link.

I ended up on the TPC 991 sway bars, where they make both the front and the rear bar and am very pleased and using a end link from a company called Powergrid, also recommended by Tom at TPC.

So I kept the Tarret Camber hats, running between 2.4 and 2.7 is sweet spot for dual usage street and track.
...

I ended up running my heights corner balanced testing higher lower, gt3, etc, and most recently dropped to about 5mm/4mm below the factory PASM-S heights and its just about right. I tried lower and wasnt happy, so you cant just run gt3 height, IMHO.

its able to keep the natural character of the car and allows me to run a stickier tire than I could with softer coils and sways.

The fact that PASM allows for a stiffer setting is what I use at the track,without that, I would not want to say for sure how this works on a non pasm car, I havent researched other 'lowering spring only' solutions which may be an option for you on a non pasm car, or you may wanna consider something like a KW V3 solution and then run a set of after market sways, not sure what your goals are.

The TPC sways worked out great, and I am open to testing another setup from Tarret if/when its available, not everything you test works out 100% and this was a case of just that

 

Thanks Gem. I'm brand new to 991s - actually don't even have the car yet (going to get it on Wednesday). But I had the choice of a PASM car and a non-PASM car and went with the second for many reasons besides the suspension. But one of my justifications was that I could spend 2-3k on the non-PASM car and reduce the high ride height while tightening the handling.

Im looking for a simple solution. Car will be 95/5 road/track. Was honestly thinking of Techart springs to drop & stiffen (as suggested by Sharkwerks) and SPASM sways, to stay close to OEM. Will probably get as much camber as I can from the stock components with an alignment. However I understand that suspensions are like baking a cake, and that certain combinations may work or not work. So honestly I was looking for a respected tuning shop that has done some development work on the non-PASM suspension, and could recommend a package deal (springs, sways, links, etc.). Tarrett is well respected, but I'm not sure they sell springs. I've reached out to BGB, and will call Sharkwerks. TPC is on my list as well, Elephant's website confuses me. Any suggestions? Obviously everyone focuses on PASM, but there are a lot of base Carreras out there.

I also thought about using SPASM springs and sways, but am not sure how SPASM springs would work with non-PASM dampers. I'm not worried about ride, more compatibility.

Honestly the ultimate goal would be to replicate the Cayman/Boxster X73 analog suspension for my 991. Thanks.

 

Update on my end - through my shop (Wright Motorsports of IMSA fame) I've been told that the Carrera 3.4 has a completely different sway bar path through the rear suspension when compared to the 3.8. Hence why there are plenty of front bars for the 3.4, butt no rear bars. Therefore I don't think TPC will be able to help me, although I will still give them a call.

That being said, Tarett has supposedly been prototyping a rear bar for the 3.4, and after several tries, is on the cusp of getting it right. This most recent prototype is being tested right now, and if it bears fruit it should be able to ship in a couple of weeks I am told.

To be honest though, with this being a street car, I am wondering if I even need upgraded bars. Driving the car for the last couple of days, I think it handles great and I cannot detect much roll (all relative - I am coming from an 87 Carrera). I got into this mod simply to reduce the wheel gap on the stock non PASM suspension, and wanted to do sways as a whole I was in there change. But since it seems so hard to get a turn key solution, I might just go with the springs (Eibach) and call it a day.