Low cost chassis bracing that works! (For 987s)
#19
Racer
Lucas, I am considering doing this on my 987.2 Spyder. Did your car have parts 3, 4 and 5 installed, so the only missing parts were 1, 2 and the bolts?
Hey guys, I've found some good low cost mods for a 987 Boxster that's really worthwhile if you're sensitive to chassis flex. This doesn't really improve performance, even though a lot of aftermarket companies that sell bracing might claim so. However, for someone like myself who hates the little bit of "reverb" vibration emanating through the car's structure over rough roads or even normal bumps, this is great couple of mods. It does increase steering precision at very high g loads as well, but it's a minor difference.
So onto the mods. For the 987 chassis, Porsche decided not to include the diagonal braces in the front compartment that the 997s have.
The mounting holes for these braces are already in place in the 987, you only need to buy the braces and the 6 bolts for this to bolt right on.
Parts:
99650423301 (DRIVER SIDE)
99650423401 (PASSENGER SIDE)
90037810001 Hexagon-Head Bolt M10 X 45 2
90007501003 Hexagon-Head Bolt M6 X 12 4
If you're on a budget, go ahead and buy the braces used on Ebay or something, otherwise they're still only $130 USD or so. The bolts can be bought anywhere or ordered through a dealer as well. These braces will slightly improve steering precision when the suspension is loaded up in corners. The difference isn't huge, but it does work. Why Porsche left them off the 987, I have no idea.
The next mod is a lower suspension brace. This one made a fairly noticeable difference in reducing overall chassis structural vibrations over bumps. And luckily it is also extremely cheap to make.
It is basically the $100 Techno brace from Pedro's garage.
Parts:
One 24" 0.75" square aluminum bar
Two M10x55mm bolts with 1.5 pitch treads (could sub for M10x50 or M10x60)
Two 10mm washers
Cost will be below $20. What you need to do is undo 1 sway bar mount under the car, undo the 2 nuts on the most rearward (towards the back of the car) mounting point of the rear suspension. Pound out the studs that the nuts were screwed onto. Insert the aluminum bar and slot it right above where the 2 studs used to be. Mark the holes onto the bar by using marker or spray paint, take the bar out, drill out the holes (10mm diameter, 3/8 drill bits will get it really close, 3/8" = 9.6mm). Insert the new M10x50mm bolts and push the washer between the bar and the bolt head, and use the original nuts to tighten the bar onto the car (48ft/lb). Reinstall the sway bar mount (17ft/lb for the 2 bolts) and you're done.
This reduced chassis vibration/reverb by a good 75%, I'm actually amazed Porsche didn't reinforce the aluminum plate which mounts onto the same bolt holes, it's a missed opportunity to make the car feel much more solid.
I also bought an aftermarket front and rear strut tower braces for my 987 Boxster S, however I think the Porsche OEM front diagonal braces will be enough for the front, and the rear one didn't do much at all, plus it was very difficult to fit a 986 rear strut brace in a 987, I wouldn't recommend it.
The overall feel of the car is now much closer to a coupe than before. I never thought the Boxster lacked much in terms of out right grip in the corners, but the steering precision was just a touch off when you're cornering right at the limit, now that's much better. The best part is that a lot of the squeaks and rattles are gone, and the ride overall just feels calmer. A lot of the bumps on the road used to make the structure of the car reverb just a tiny bit, making it feel a bit busy. Now it is more solid and "refined" if you will.
As for the 987 Cayman, it already has a top, so I doubt these braces will make much of a difference. That said, how can you go wrong for less than $100 in parts for these braces?
-Lucas
So onto the mods. For the 987 chassis, Porsche decided not to include the diagonal braces in the front compartment that the 997s have.
The mounting holes for these braces are already in place in the 987, you only need to buy the braces and the 6 bolts for this to bolt right on.
Parts:
99650423301 (DRIVER SIDE)
99650423401 (PASSENGER SIDE)
90037810001 Hexagon-Head Bolt M10 X 45 2
90007501003 Hexagon-Head Bolt M6 X 12 4
If you're on a budget, go ahead and buy the braces used on Ebay or something, otherwise they're still only $130 USD or so. The bolts can be bought anywhere or ordered through a dealer as well. These braces will slightly improve steering precision when the suspension is loaded up in corners. The difference isn't huge, but it does work. Why Porsche left them off the 987, I have no idea.
The next mod is a lower suspension brace. This one made a fairly noticeable difference in reducing overall chassis structural vibrations over bumps. And luckily it is also extremely cheap to make.
It is basically the $100 Techno brace from Pedro's garage.
Parts:
One 24" 0.75" square aluminum bar
Two M10x55mm bolts with 1.5 pitch treads (could sub for M10x50 or M10x60)
Two 10mm washers
Cost will be below $20. What you need to do is undo 1 sway bar mount under the car, undo the 2 nuts on the most rearward (towards the back of the car) mounting point of the rear suspension. Pound out the studs that the nuts were screwed onto. Insert the aluminum bar and slot it right above where the 2 studs used to be. Mark the holes onto the bar by using marker or spray paint, take the bar out, drill out the holes (10mm diameter, 3/8 drill bits will get it really close, 3/8" = 9.6mm). Insert the new M10x50mm bolts and push the washer between the bar and the bolt head, and use the original nuts to tighten the bar onto the car (48ft/lb). Reinstall the sway bar mount (17ft/lb for the 2 bolts) and you're done.
This reduced chassis vibration/reverb by a good 75%, I'm actually amazed Porsche didn't reinforce the aluminum plate which mounts onto the same bolt holes, it's a missed opportunity to make the car feel much more solid.
I also bought an aftermarket front and rear strut tower braces for my 987 Boxster S, however I think the Porsche OEM front diagonal braces will be enough for the front, and the rear one didn't do much at all, plus it was very difficult to fit a 986 rear strut brace in a 987, I wouldn't recommend it.
The overall feel of the car is now much closer to a coupe than before. I never thought the Boxster lacked much in terms of out right grip in the corners, but the steering precision was just a touch off when you're cornering right at the limit, now that's much better. The best part is that a lot of the squeaks and rattles are gone, and the ride overall just feels calmer. A lot of the bumps on the road used to make the structure of the car reverb just a tiny bit, making it feel a bit busy. Now it is more solid and "refined" if you will.
As for the 987 Cayman, it already has a top, so I doubt these braces will make much of a difference. That said, how can you go wrong for less than $100 in parts for these braces?
-Lucas
#20
Racer
#21
Addict
Rennlist Member
Rennlist Member
#22
Racer
Thanks Afshin! I ordered the parts from Suncoast. With the "console" part (0 997 504 359 00, $99.55 from Suncoast), the total was 234.05 plus shipping. One of the parts was only available in Germany, so it may take 4 weeks for delivery. I am also ordering the Rennline rear subframe stabilizer, which appears to serve the same function as Pedro's Technobar with the same attaching points. When I get the parts installed on my 987.2 Spyder, I will have the car aligned and corner balanced, then post my thoughts.
#23
Rennlist Member
I tried to buy the front strut/brace stuff for my 2011 Boxster S (987.2) from a P-dealer online source and they wouldn't sell it to me because the parts catalog says it is only for 986 cars. (part # 99650423401 and 99650423301)
So I am asking people with 987.2 to confirm that they have bought these 2 parts and successfully (and easily) installed them in their 987.2 vehicles. I'll then order them from my local dealer.
TIA, CIA, etc,
fred
ps: I know that this thread is filled with happy users with 987.2, but if I buy the parts I can't give them back, so I want to make triple sure that they fit.
So I am asking people with 987.2 to confirm that they have bought these 2 parts and successfully (and easily) installed them in their 987.2 vehicles. I'll then order them from my local dealer.
TIA, CIA, etc,
fred
ps: I know that this thread is filled with happy users with 987.2, but if I buy the parts I can't give them back, so I want to make triple sure that they fit.
#24
Addict
Rennlist Member
Rennlist Member
I tried to buy the front strut/brace stuff for my 2011 Boxster S (987.2) from a P-dealer online source and they wouldn't sell it to me because the parts catalog says it is only for 986 cars. (part # 99650423401 and 99650423301)
So I am asking people with 987.2 to confirm that they have bought these 2 parts and successfully (and easily) installed them in their 987.2 vehicles. I'll then order them from my local dealer.
TIA, CIA, etc,
fred
ps: I know that this thread is filled with happy users with 987.2, but if I buy the parts I can't give them back, so I want to make triple sure that they fit.
So I am asking people with 987.2 to confirm that they have bought these 2 parts and successfully (and easily) installed them in their 987.2 vehicles. I'll then order them from my local dealer.
TIA, CIA, etc,
fred
ps: I know that this thread is filled with happy users with 987.2, but if I buy the parts I can't give them back, so I want to make triple sure that they fit.
#25
I tried to buy the front strut/brace stuff for my 2011 Boxster S (987.2) from a P-dealer online source and they wouldn't sell it to me because the parts catalog says it is only for 986 cars. (part # 99650423401 and 99650423301)
So I am asking people with 987.2 to confirm that they have bought these 2 parts and successfully (and easily) installed them in their 987.2 vehicles. I'll then order them from my local dealer.
TIA, CIA, etc,
fred
ps: I know that this thread is filled with happy users with 987.2, but if I buy the parts I can't give them back, so I want to make triple sure that they fit.
So I am asking people with 987.2 to confirm that they have bought these 2 parts and successfully (and easily) installed them in their 987.2 vehicles. I'll then order them from my local dealer.
TIA, CIA, etc,
fred
ps: I know that this thread is filled with happy users with 987.2, but if I buy the parts I can't give them back, so I want to make triple sure that they fit.
#26
Rennlist Member
AFSHIN: I actually didn't, and should have. My car is from Stuttgart so I figured (per a previous post) that it did have the mounting points. I've just looked at the car for the 1st time and see that I'll have to remove various plastic trim pieces in order to see the mounting points. IS THAT CORRECT? I don't have time to do it now, and will look in the morning.
Are those trim pieces easy to remove AND REINSTALL?
TIA,
fred
Are those trim pieces easy to remove AND REINSTALL?
TIA,
fred
#27
Addict
Rennlist Member
Rennlist Member
Fred just pull the battery trim cover and look to the driver side strut tower for the holes. Should take 2 minutes to verify
#28
Rennlist Member
AFSHIN: Woefully incorrect assessment of how long it would take to check my car. It took ONE minute, not two.
My car DOES have the 2 threaded holes. So that means I CAN install the 996-class struts into my car!! I will order the parts right now.
THANKS FOR YOUR HELP. (TO install, I'll have to remove those trim pieces, and then put them back, yes? . Is that difficult?)
My car DOES have the 2 threaded holes. So that means I CAN install the 996-class struts into my car!! I will order the parts right now.
THANKS FOR YOUR HELP. (TO install, I'll have to remove those trim pieces, and then put them back, yes? . Is that difficult?)
#29
Addict
Rennlist Member
Rennlist Member
Trim removal should take 10 minutes give or take
#30
Rennlist Member
Okay, curiosity finally forced me to take the 1-minute look at my '05 Boxster S. Well, I'll be... it has holes in the strut tower too. Nice!
If someone can please advise the process for trim piece removal, I'd be grateful.
Thanks!
If someone can please advise the process for trim piece removal, I'd be grateful.
Thanks!