Subaru Impreza GC8 & RS Forum & Community: RS25.com - View Single Post - Equinox's RBP V8 EJ207 STi Swapped RSTi - Twinscroll Braps Inside
View Single Post
Old 10-18-2015, 08:49 AM  
equinox92
They call me Garrett
 
equinox92's Avatar
 
Fav Mod: Park Bench
Join Date: Nov 2010
Location: Detroit, Michigan
Trader Rating: (53)
Posts: 4,057
Default

GC8 STi Tarmac/Gykhana Springs

Finally got my hands on set of these and wasted no time putting them on the car.

As it turned out, I had STi WAGON springs on the car, which was not doing my coupe any favors.

Simple swap, simple comparison.

Did the rears first:



As you can see, the spring on the left (STi Wagon) doesn't have as much coiling at the top as an STi sedan or coupe spring. Compared to the tarmac spring though, there's a LOT going on that's different.

The tarmac spring (right) has a lot of coiling at the bottom that was very soft, and the standard coiling in the middle also grew in diameter and was VERY stiff. From what I could tell the bottom coils took up the weight of the car, and also compressed when the tophat went on. So from my reasoning, those coils are there to take up all the small bumps and whatnot from daily driving, where when they get compressed in a static turn, the real stiff part "takes over".

I could be wrong, but that's what I have noticed so far.

Anyways, rear struts with the spring on:



Mostly took this picture to show off the Ohlins, but more importantly the green spring dot at the bottom which denotes these as the STi Tarmac springs.

And a front comparison:



Kind of a crappy angle, but it's business as usual here in the front. Little bit of extra coiling on the top and bottom compared to the STi wagon spring (left). Also should note that the front wagon spring seems to be exactly the same as STi coupe/sedan fronts.

We can also see in this picture the double pink dots on the bottom that denotes these are the tarmac springs.

And on the strut:



Ride Height

Measured from the center of the axle nut to the fender.

STi:

RF - 13 7/8in
LF - 13 7/8in
RR - 13 6/8in
LR - 13 6/8in

Tarmac:

RF - 13 5/8in
LF - 13 5/8in
RR - 13 3/8in
LR - 13 3/8in

So in the front there's a drop of 1/4in and in the rear 3/8in which comes out to ~6mm front and 10mm rear

Perfect!

First Impressions:

AWESOME! These are a perfect combination spring for DDing and taking corners HARD. Rear seems way more planted, front isn't getting a huge load on it. No rubbing with my 17x7.5 wheels and paired with the Ohlins keeps everything in line.

I have an AutoX coming up in a week and I can't wait to drive with these for the first time as well as the 04 STi rack for the first time.

Even with just a day of driving I am already convinced that these Tarmac springs paired with Ohlins adjustable is one of the ultimate GC setups for DDing and AutoX/mild track use.
__________________
Tuned Detroit - Automotive Blog, check it!

Last edited by equinox92; 10-18-2015 at 11:42 AM..
equinox92 is offline   Reply With Quote