club.liberty.asn.au

Hi All,
I have been reading the info about steering racks below at this link:
viewtopic.php?f=16&t=31075[url][/url]

Can someone provide any detail if the Gen 4 post face 2007-2009 GT-B steering rack are the same as
the 2007-2009 GT-B TBSTI?

I find the GT-B with a few suspension mods handles like on rails and the road feel is excellent.
I would expect even better from a low km STI version with similar suspension, rims and tyres!

However even after a wheel alignment by a Subaru specialist I have felt the STI feels a little vague when driving in a straight line. It also loves to follow the camber of the road slightly left or right. It does have slight tow in to help with this.

The steering wheel to rack doesn't seem to have play in it.

What is the issue and what can could be checked?
Thanks,

Same 2.7 turn racks in postfl GT & tbSTi.
Preface GT got 2.5 turn racks.

Check your LCA bushes for cracks, steering knuckle for play…

I wasn’t happy with the steering initially and wound up with an STi solid steering u-joint, Whiteline RCA kit, AVO caster adjust LCA bushes, Whiteline rear upper outer caster correction bushes and 235 40 18 8.5 +35 wheels and Shockworks coilovers, lowered slightly with a finger gap between tyre top and guard lower edges, and all within stock alignment specs.

I’d say the important parts for improved steering feel are the RCA kit, added caster and the solid knuckle.

The pokey wider tyres with slightly lower profile than stock adds weight to the steering and helps clear the added caster.

The caster mod helps with straight line stability, return to centre and dynamic caster, at the expense of some added tyre shoulder wear. The latter isn’t an issue if the tyres are regularly rotated. I’m now on PS5 which can potentially be fully rotated side to side as well as front to rear (fact check required).

Still on the to do list: Shockworks caster adding front top plates: +7’ caster possible, install prefl rack or jdm GR STi 2.3 turn rack.

bigBADbenny wrote:Same 2.7 turn racks in postfl GT & tbSTi.
Preface GT got 2.5 turn racks.

Check your LCA bushes for cracks, steering knuckle for play…

I wasn’t happy with the steering initially and wound up with an STi solid steering u-joint, Whiteline RCA kit, AVO caster adjust LCA bushes, Whiteline rear upper outer caster correction bushes and 235 40 18 8.5 +35 wheels and Shockworks coilovers, lowered slightly with a finger gap between tyre top and guard lower edges, and all within stock alignment specs.

I’d say the important parts for improved steering feel are the RCA kit, added caster and the solid knuckle.

The pokey wider tyres with slightly lower profile than stock adds weight to the steering and helps clear the added caster.

The caster mod helps with straight line stability, return to centre and dynamic caster, at the expense of some added tyre shoulder wear. The latter isn’t an issue if the tyres are regularly rotated. I’m now on PS5 which can potentially be fully rotated side to side as well as front to rear (fact check required).

Still on the to do list: Shockworks caster adding front top plates: +7’ caster possible, install prefl rack or jdm GR STi 2.3 turn rack.

Thank you for the advice.
I drove the 07 GT today to compare to the 08 STI. The steering on the GT is heavier but gives more initial road feel.
I have tried both sets of rims/wheels on both cars with little or no noticeable difference.
18x 7.5, STI rims 225/40/18
18x7.5 Foz rims (48 offset) 235/40/18.

The STI includes minimal alteration but includes:
Alloy OE LCA's with rear NEW Urethane LCA bushes and NEW front OE,
22mm front sway bar with urethane bushes,
20mm rear OE STI sway bar,
STI springs,
Reco Bilstein's and new top hats.

The GT includes:
Rear NEW Urethane LCA bushes, complete new LCA's and replaced front urethane bush with OE,
22mm front sway bar with urethane bushes,
20mm rear sway bar with urethane bushes,
OE GT springs,
Reco Bilstein's and new top hats.

Both cars have STD wheel alignment and both handle like on rails.
The only difference is the STI feels lighter in the steering and therefore less feedback.

I shall check the steering rack bushes and look at your caster and RCA kit improvement. It could be the STI OE knuckle but it looks sound.

Other than the Brembo's the GT feels incredible to drive as both same bolt on mods and similar tune.
GT brakes with Intima SR and slotted rotors stops on a dime if pushed but I feel the booster may be tired. Any suggestions on replacement? will a Gen 5 Lib booster fit?

Thanks for advice.

You can always load up two browser windows with each cars VIN search on eg Partsouq com, drill down to the steering parts page and see if there any difference in the eg the p/s pump and steering rack part numbers.

Or just try visual inspection of the stickers/imprint on the rack & pump?

You might try a 365mm steering wheel as well, the smaller diameter makes the steering wheel ever so slightly harder to turn.

Thanks for advice Ben, I may be onto something after discussing the flexible steering damper with another Subaru owner with a 2015 WRX. He said he experienced exactly what I have with on center straight line feel of low feedback.
He added the steering damper stiffening kit and now has perfect feedback.

I noticed both my 07 and 08 have this flexible damper near the knuckle. What I don't understand is why the 07 feels stiff.

Yesterday I noticed the 08 Invidia bell mouth of the dump pipe sits much closer to the rubber joint and fire wall than the 07 dump pipe.

I'm wondering is it the heat from the 08 dump pipe contributing to a more flexible rubber damper joint which makes it feel more loose in the steering?

Be interested to hear if anyone else has experienced this and how they rectified? I could try a Heat shield mat?

The damper stiffeners sound worth a go also.

I would heat-wrap or use one of those Perrin (etc) dump pipe blankets on general principles.

Can't be good for any parts to have heat radiating off the dump pipe that close to them.

Removing a dump pipe for wrapping is pretty easy, although wrap is a bit horrible apparently (never used it). The special blankets don't even require dump pipe removal - they just lace up with safety wire around some buttons.

Yowie wrote:I would heat-wrap or use one of those Perrin (etc) dump pipe blankets on general principles.

Can't be good for any parts to have heat radiating off the dump pipe that close to them.

Removing a dump pipe for wrapping is pretty easy, although wrap is a bit horrible apparently (never used it). The special blankets don't even require dump pipe removal - they just lace up with safety wire around some buttons.

Thanks for advice,
What do you think of this exhaust wrap;
Exhaust Wrap Titanium Heat Resistant 10M x 50mm 2000F + 10 Stainless Cables Ties

https://www.ebay.com.au/itm/19496997733 ... gK4hPD_BwE[url][/url]

This seems a cost effective solution. The bell mouth zip style coveres are very expensive but include titanium or carbon fibre. Any other suggestions appreciated.

I don't have any hands-on experience with heat wrap so this set of comments is pretty lightweight:

Assuming that particular wrap isn't some terrible scam type stuff it's probably like any other. There are plenty of videos on effective heat wrapping technique (wetting the wrap, spraying with heat-resistant paint when finished to seal it down? etc).

Some people talk about wrap being quite hard on headers.

Here we have a dump pipe (after the turbo has taken a lot of heat energy out of the exhaust) so it's probably less of a concern.

FYI my Xforce stainless dump pipe (wrapped in a Perrin blanket for years) showed different colouration (more blue than gold) on the insulated part when I recently took it off, but no other damage (other than a cracked welded hanger at the gearbox end that needed repair - unrelated to heat).

As such, I would probably not get too hung up on different theories. You can always replace the dump pipe in a few years time if it turns out to be a damage-causing problem.

The usual fix for insulating the exhaust from the cv boot is a simple metal heat shield.

Some aftermarket dumps have a curved stainless steel plate on standoffs, or just use 3 layer heat shield material and metal zip clamps, aka cv boot clips.

Lava wrap can be a fire hazard if it becomes soaked with oil.

I fitted the Perrin steering damper support quadrants and the steering is now sharp and not really much additional vibration from the road. The steering does seem lighter than our other GTB.

bigBADbenny wrote:The usual fix for insulating the exhaust from the cv boot is a simple metal heat shield.

Some aftermarket dumps have a curved stainless steel plate on standoffs, or just use 3 layer heat shield material and metal zip clamps, aka cv boot clips.

Lava wrap can be a fire hazard if it becomes soaked with oil.

Thanks thats a good tip regarding fire hazard. agree