Raceseng Shock Tops Questions - 1" or 2"

[TrogDor the Burninator]

I've been noticing quite a bit of rear driver-side noise indicative of my RCE Tarmac II Clubsport coilovers hitting the bump stop. My car is lowered somewhat, but not terribly much. I'd say about an inch currently.

I'm interested in the Raceseng Shock Tops, but I'm curious as to how to decide on the proper size. The RCE Tarmac 2's are KW V3s with RCE 400 lb springs (7.1kg).

What is the maximum recommended travel for the KW V3's? Obviously ride height adjustment is crucial to knowing how much travel you have, but are there some visual cues or measurements I can take to help put with this decision?

I do track this car quite a bit in NASA, so I'm concerned about extending too far and ruining the coils prematurely, or upsetting the performance of the coil altogether.

Anyone have experience with these on the track or street?

http://www.raceseng.com/shock-top-2-...baru-brz-2013#

@Raceseng
@Racecomp Engineering

[eyedeez]

http://docs.kwsuspension.de/ea-KWGFwEA-h68658004.pdf

This is the V3 installation guide. This may or may not be of use to you.

[wparsons]

The bump stops should be quite silent when you hit them, and they're progressive rates so it shouldn't be a solid thump.

Further, if you're actually hitting the bump stop, those upper mounts won't help you at all with fixing this issue. You'll either need to raise it up or run higher rate springs. I suspect it might be something else that you're hearing though, possibly the end links hitting the LCA?

Now, if you were bottoming out the shock internally before hitting the external bump stop these would definitely help.

[TrogDor the Burninator]

Hmmmm ... now I'm wondering if my shock isn't extended high enough ... as in time of their installation. How far does the shock normally extend up past the rear shock tower?

I have some image searches to perform apparently. I'll post a pic of my current install height shortly.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

[Racecomp Engineering]

An inch drop isnt a problem. I would double check your install....top nuts may be loose?

Anyway, the 1 inch drop raceseng rear mounts would be my choice if your sticking with an approx 1 inch drop from stock.

- Andy

[TrogDor the Burninator]

So I checked the left rear shock mount for any play / looseness ...

It wasn't loose. However when I tried to loosen the top nut (locking nut) it would not loosen, instead it just turned the entire shock piston.

Sooooo ... what does that mean exactly?

I made sure I wasn't just turning both nuts at the same time with my deep socket ...

Here is a pic of the shock mount from the trunk:

[wparsons]

Did you do the initial install yourself, or have a shop do it?

You probably need a pass through socket on the nut, and then either an allen key or smaller socket (depending on the shock design, stock is an allen key) to keep the shaft from rotating.

[7thgear]

i asked the following question in the "suspension model" thread but no one answered.

by raising the bumpstop engagement in such a way you're also raising how high the wheel can go in the wheel arch

which also affects how high the LCA/UCA has to move up, a theoretical inch or even two higher than it was inteded for.

also generally the bumpstop is an integral part of the system.. especially in a coilover. If you move it up an inch or two, that's an inch or two of coil bind.. can the coils themselves handle it or will they be compressed?

they probably did the math... but i'm not seeing these issues discussed... and i think it should... and that this would be highly application specific.

[Wepeel]

Originally Posted by 7thgear

i asked the following question in the "suspension model" thread but no one answered.

by raising the bumpstop engagement in such a way you're also raising how high the wheel can go in the wheel arch

which also affects how high the LCA/UCA has to move up, a theoretical inch or even two higher than it was inteded for.

also generally the bumpstop is an integral part of the system.. especially in a coilover. If you move it up an inch or two, that's an inch or two of coil bind.. can the coils themselves handle it or will they be compressed?

they probably did the math... but i'm not seeing these issues discussed... and i think it should... and that this would be highly application specific.

I know I brought this up before. Depending on the setup you could be putting yourself into a position of coil bind. Maybe not, but it's something I would definitely do the math on with perch height, spring travel, block length, damper stroke, etc etc etc.

[Racecomp Engineering]

Originally Posted by TrogDor the Burninator

So I checked the left rear shock mount for any play / looseness ...

It wasn't loose. However when I tried to loosen the top nut (locking nut) it would not loosen, instead it just turned the entire shock piston.

Sooooo ... what does that mean exactly?

I made sure I wasn't just turning both nuts at the same time with my deep socket ...

Here is a pic of the shock mount from the trunk:

That's normal....

Give us a call and Myles can probably help you troubleshoot the noise...they should be silent especially with stock tops.

- Andy