Raising the rear

[Mahtava]

Hi guys,

I'm looking to raise the rear of my car.
What are my options?

I have a MY07 GT Spec.B, 18x8 (+45) Tenzo Cuzco with 235/40/18.
Wheels and tyres are currently the only modifications done to the car.

The ride is awesome with just me but when I have passengers in the back or luggage (not game to try simultaneously) in the boot the rear wheels always hits the guard on bumps and corners.

Fender to tyre height is different on the front than it is on the rear.
I'd like to just lift the car of the can 15-30mm if that is possible.
I will post some pics tomorrow hopefully.

Any information is appreciated.
Thanks in advance.

[DrivesLikeJehu]

There are two different thickness spacers available for the rear damper assy. One uses the standard studs, the other needs longer replacement studs.
Those who fit STI pink springs often buy the WAGON spec rears to give an even stance (WGNs are same rate, but slightly longer, giving a slightly higher comparative height).
So, maybe spring options are:
1) Investigate whether standard Spec B WAGON springs are slightly longer than yours. Someone here with a wagon will have upgraded to coilovers and have them in the shed ?
2) Look at a higher spring rate option. Eg: King springs standard height, maybe wagon spec again ? King springs have a reputation for being harsh, so they're definitely stiffer . In fact, almost any aftermarket spring will be higher spring rate, and most brands list a "standard ride height" version, as well as a lowered one.
3) I was reading on a US forum where they discussed the visual bum sag on Gen IVs and someone referred to using two spring seats on the spec Bs. I haven't dismantled my spare rear set yet to see if this is viable, but it looks like the seat is a seperate part on the billie rears. It seems feasible. It would give slightly higher spring preload, but so would longer wagon springs. I believe more preload actually HELPS your "under load" problem, but too much destroys the ride, apparently.
To me, if it only rubs when there is load in the rear, increased springrate would be my preferred fix, but bear in mind that if you increase rear rate only, this will effect the handling balance. I'm inclined to think, a subtle increase will actually improve it (less mid-corner understeer) but be prepared. If you look at, for example, WRX to STI spring rate, they increased the rear rate by more than the front, from memory.
Of course, having done it, I'd put in a vote for STI pinks , but it's a relatively expensive option.
30mm sounds like a LOT to raise it, tho'. That amount, potentially, changes your rear alignment geometry, and would require an alignment, possibly with camber/toe changes needed (adding to the cost).
I'm glad I read your thread, tho' . I just put 225s on mine, and wondered if I could've fitted 235s. Have you determined if it rubs inside edge, or outside edge ? I'm guessing outside, with the offset you're running.

[Greenman]

There are two different thickness spacers available for the rear damper assy. One uses the standard studs, the other needs longer replacement studs.
Those who fit STI pink springs often buy the WAGON spec rears to give an even stance (WGNs are same rate, but slightly longer, giving a slightly higher comparative height).
So, maybe spring options are:

+1 ...good advice.

[coyote]

Yes, you need wagon springs.

I've got heaps.

$50 if you want standard spec b.

$100 if you want Kings.

[DrivesLikeJehu]

I don't think he's coming back, guys
I went and re-read the motorbikers guide to preload and re-read the OP, and I'm now convinced wagon springs plus a pair of spacers would be the best fix.
(If coyote can confirm Spec B standard Wgn springs ARE longer than sedan). OP thinks the current ride is "awesome". (I found it a little wallowy).Kings will spoil that for him.

[teK--]

Wagon rear springs are definitely higher when fitted to a sedan.

The front is meant to be higher than the rear. It is for wheel clearance when at full lock.

Hi guys,

I'm looking to raise the rear of my car.
What are my options?

I have a MY07 GT Spec.B, 18x8 (+45) Tenzo Cuzco with 235/40/18.
Wheels and tyres are currently the only modifications done to the car.

The ride is awesome with just me but when I have passengers in the back or luggage (not game to try simultaneously) in the boot the rear wheels always hits the guard on bumps and corners.

Fender to tyre height is different on the front than it is on the rear.
I'd like to just lift the car of the can 15-30mm if that is possible.
I will post some pics tomorrow hopefully.

Any information is appreciated.
Thanks in advance.

[Mahtava]

So the recommendation is to put a set of Spec.B wagon springs in the rear...
Should I be changing the springs in the front too, to maintain the front being slightly higher than the rear?

As per DrivesLikeJehu comments I'm not inclined to put Kings in as they will make the ride harsher...

I'm also looking at putting 225/40's (borrow from a mate) on my wheels to see if that will eliminate the tyre rubbing issues.

[teK--]

Wagon fronts are same height as sedans, so no you don't need to change them. The car is going to handle differently though if you just jack the back up.

[DrivesLikeJehu]

I'm a newbie here, but I'll give the long answer no-one else has time for, and the old-timers can correct if necessary .
WAGON springs in a sedan is a common fit, to improve the visual impression the rear is lower. Front springs are the same for sedan/wagon. (No need to change).
You need to think of it as a visual impression, because the eye is drawn to the wheel/fender gap. I couldn't find my tape measure, but I expect if you measure off equivalent points on the lower sill between the wheels, the front of the floorpan isn't higher. It just looks like it, because they made the wheel arch bigger/ higher on the front to allow the front wheel clearance to turn. For an extreme example, check out a VN commodore image:
http://www.google.com.au/imgres?imgurl= ... CB4Q9QEwAQ . Imagine that rear wheel arch profile on the front ! So, we know what tek is saying, but he may have been a bit misleading in the way he said it .
The BIG advantage of wagon springs is they should increase your rideheight, AND your preload, because they are longer springs on the same damper length.
If you can try a different tire size for free, do it, but I spent a lot of time trying to use tyre size to improve the severe speedo error. If wagon springs, plus a top spacer, plus maybe an extra spring seat, fixed my tyre rub AND speedo AND visual stance, I'd persevere that far, but thats just me. That's exactly the route I was heading, before I scored some cheap Pinks, and I may still try the spring seat or spacer, once my rideheight has completely settled.
225/40/18 will make your speedo 2% WORSE than the 8%-ish it's already out.
Update: LOL at crosspost.
As for the handling change, you're potentially heading towards a rear weight transfer/ roll oversteer balance, but the engineered-in understeer is pronounced enough, that I don't think it'll hurt if it's just a small change (15mm-ish). You're still WAY short of an outback ride height/ roadholding level, and I don't see too many of those collecting lamp posts on the outside of bends . If you can feel the change and don't like it, a slight rear swaybar increase (17-19mm) or even just poly bushes would likely restore the familiar handling feel.

[teK--]

Thanks Lance for posting what I cbf typing . Agree totally with what you said.

[DrivesLikeJehu]

Fixed it yet, Mahtava ?