Mid Engine SVX concept.

[Dessertrunner]

I think MRT summed it up well in this artical from there web site when they talk about suspension.

"Subaru has tuned the suspension
settings of a standard WRX to cater for a wide range of
drivers. This means handling characteristics have been
set for the lowest common denominator, or drivers with
dubious skill levels, and those that demand ride comfort
over performance."

Kind of changes the thinking a bit.

I need to do as Matt suggested in the start then worry about it later. I can model the suspension behaviour on the 3D cad later

Tony
http://www.mrtrally.com.au/performan...x_book/P96.pdf

[smc]

McNeil Racing's Mid Size T-Style fiberglass/carbon fiber dash are within spec of our stock dashes. I plan on using them for my car. http://www.mcneilracinginc.com/off-r...berglass/dash/


For speedglass for the svx, talk to Talor Percy's http://www.percysop.com/racing_windshields.html
Contact Patrick at 816-765-5011 here in the states.
They built a new facility just for the speedglass (aka lexan) and can get you a custom set with quick turn around. you will need to provide a set of svx glass for them to make the copys from. However, the stock SVX glass is not all the heavy.
Rear Glass: 21 lbs.
Rear Side Upper Glass: 6 lbs. each
Rear Side Lower Glass: 3 lbs. each
Front Side Upper Glass: 6 lbs. each
Front Side lower Glass: 6 lbs. each.

Id just replace the flat, roll down sections and leave the rest.

Less the front windscreen there is only 63lbs worth of glass on our car. Honestly, I expected it to be more than that.

At most, with lexan you would only be shaving off perhaps 30 lbs.
Not worth the $800+ (usd) it would cost. Not to mention the cost of new weather stripping ( nearly $500 from Subaru ) and install.

[bazza]

Originally Posted by Dessertrunner

I think MRT summed it up well in this artical from there web site when they talk about suspension.

"Subaru has tuned the suspension settings of a standard WRX to cater for a wide range of drivers. This means handling characteristics have been set for the lowest common denominator, or drivers with dubious skill levels, and those that demand ride comfort over performance."

Kind of changes the thinking a bit.

I need to do as Matt suggested in the start then worry about it later. I can model the suspension behaviour on the 3D cad later

Tony
http://www.mrtrally.com.au/performan...x_book/P96.pdf

That's 100% spot on and it's the same with pretty much every single car on the road bar supercars - they're all built for the lowest common denominator. Just bare in mind though - that article was written back in the early 2000's and things have moved on in a big way especially in the Subaru mods world. A standard WRX back when that article was written was quite a boring unit although that said - through the hills the only none supercar street cars that could really keep up would be the EVO's and GTR's.

This is what happens when you goto town on the mods:
http://www.youtube.com/watch?v=OOP3_1TsXs4
http://www.youtube.com/watch?v=BAUG7w_GtmU

[oab_au]

Originally Posted by Dessertrunner

Don't agree as the SVX has the third arm coming from the front to the wheel hub the same as your car. using flexiable trailing arms will require that to stay. Given that the arm has a very short length it would be effected by any rid heigth change the most of all.
A rigid arm can still offer toe in adjustment because one bush can be adjusted on a ecentic.

It maybe possiable to move the inner trailing arms to origanl position and leave all that fixed as Matt suggested using standard arms just with a couple of pivot positions in height for adjustment.

Tony

That trailing link takes most of the drive thrust from the wheel to the body, and the braking forces.
It also provides some rear wheel steer.
On a left turn, as the body rolls to the right, the strut compresses. The trailing arm moves through a shorter ark so, as the wheel goes up, the arm pulls it forward, causing the wheel to toe in, to steer the rear into the corner.

The arms position on the car now, is designed to suit the car as it is. With an engine in the rear, the amount of rear steer has to change to suit the new conditions. Lengthing the arm reduces the change, and changing the height of the front pivot, changes the rate of change to wheel movement.

Harvey.

[Dessertrunner]

Originally Posted by oab_au

That trailing link takes most of the drive thrust from the wheel to the body, and the braking forces.
It also provides some rear wheel steer.
On a left turn, as the body rolls to the right, the strut compresses. The trailing arm moves through a shorter ark so, as the wheel goes up, the arm pulls it forward, causing the wheel to toe in, to steer the rear into the corner.

The arms position on the car now, is designed to suit the car as it is. With an engine in the rear, the amount of rear steer has to change to suit the new conditions. Lengthing the arm reduces the change, and changing the height of the front pivot, changes the rate of change to wheel movement.

Harvey.

Harvey I think you hit the nail on the head again, you have got it right except that the wheel moves back when it comes up due to the trailing link sloping down towards the back.

Left brain tells me that the outside wheel goes back, the front of the wheel turns out and that enable the front of the car to turn in more thus reducing the understeer in the car. Back of car wants to swing around,

How does that sound for a load of bull. Even if I have it slightly wrong in behaviour what you say the reason its there now makes sense Harvey.
Thanks.

Tony

[oab_au]

Originally Posted by Dessertrunner

Harvey I think you hit the nail on the head again, you have got it right except that the wheel moves back when it comes up due to the trailing link sloping down towards the back.

Left brain tells me that the outside wheel goes back, the front of the wheel turns out and that enable the front of the car to turn in more thus reducing the understeer in the car. Back of car wants to swing around,

How does that sound for a load of bull. Even if I have it slightly wrong in behaviour what you say the reason its there now makes sense Harvey.
Thanks.

Tony

The arm is slightly down in the static position, I reckon that it is flat in running, so that it swings up to pull the wheel forwards, toe in?
This happens with a fair bit of body roll, so the load is on the outside wheel, that does the steer.

Harvey.

[Dessertrunner]

Did some test work with the new sub frame design and I think the pipe won't work as the the main engine support. The engine load is down twards the ground and the pipe wants to flex, I will change the beams to two rails 75mm by 50mm by 2mm wall. In this way I should get a more rigid engine support.

Anyone have a opinion???

[Dessertrunner]

We are right but wrong Harvey,
The wheel DOES NOT toe out or in. I have been straching my head thinking if the wheel toed out or in there would be problems. If the wheel toed out the car would become unstable in the ass.
So what the smart buggers do is they move the wheels foward and back but maintain the parrell between each wheel. the centre line of the two wheels changes so if I am going around a left hand corner the left wheel lifts and it moves forward, the two laterial arms are the same length so they don't change the angle of the wheel just move it forward. THe left hand wheel raises so moves back staying parrel with the other side.
Now the centre line between each wheel is off line with the angle of the line of the car. in short the two back wheels are pointing towards the left causng the back of the car to want to go left, net result reduced understeer.

Sounds interesting.

So if this assumption is right what more can we do to make it better?
Tony

[Dessertrunner]

Tried farming with RHS and it didn't happen, went back to pipe. Settled on final design and also designed the jig to hold all the parts in place while they are being welded. As you can see the suspenion mounts can be moved and adjusted. The overall height of the sub frame relitive to the support point on the chasse can be changed as well.

Here it is in 3d pdf, the main frame that goes in the car is the red part. We will start cutting the set for the jig this afternoon.

Tony

[bazza]

Originally Posted by Dessertrunner

Tried farming with RHS and it didn't happen, went back to pipe. Settled on final design and also designed the jig to hold all the parts in place while they are being welded. As you can see the suspenion mounts can be moved and adjusted. The overall height of the sub frame relitive to the support point on the chasse can be changed as well.

Here it is in 3d pdf, the main frame that goes in the car is the red part. We will start cutting the set for the jig this afternoon.

Tony

Wow - the stuff you come if with in CAD is amazing.

[Dessertrunner]

Has anyone weighted the rear boot and the front bonnet. Also what about the front and rear bumper bar?

I am trying to figure were the total weight of 1,600kg's of our car comes from and how much can be removed.

Tony.

[SVXRide]

Originally Posted by bazza

Wow - the stuff you come if with in CAD is amazing.

Ditto! Nicely done. Tony! The Acrobat software has come a long way regarding visualization. I take it you're using a high end CAD program and saving the file as a 3D pdf?? Are the green pieces just your welding jig and the blue representing the mounting points on the SVX frame?

Thanks.

Bill

[SVXRide]

Originally Posted by Dessertrunner

Has anyone weighted the rear boot and the front bonnet. Also what about the front and rear bumper bar?

I am trying to figure were the total weight of 1,600kg's of our car comes from and how much can be removed.

Tony.

Tony,

I know just about everything has been weighed in the past. OT can probably pull everything out of his head. I'll see what I can dig up.

Cheers
Bill

[SVXRide]

Tony,
Here's what I was able to dig up after a little searching:

Driver seat (leather with electric controls)- 68 lbs.
Passenger seat- 49 lbs.
Rear seat bottom- 13 lbs.
Rear seat back- 24 lbs.
Factory type spare tire- 28 lbs.
Factory wheel complete with tire, balanced and inflated- 47 lbs.
(Note only a 19 lb. difference between those meaty real wheel assemblies and the goofy temporary spare. Those wheels are fairly light.)
Standard type battery- 31 lbs.
Back glass- 20 lbs
Rear 1/4(stationary) glass- 5 lbs
Rear 1/4(moving) glass- 3 lbs
Rear window regulator- 4lbs.
Front(moving) glass- 8 lbs
Entire AC system (less ducts)- 30 lbs.
Bumper core- 28 lbs.
Entire sunroof assembly (including motor, cables, tracks, wiring)- 29 lbs.
Hood- 46 lbs.
Entire trunk assembly (including lifters, hinges, lights, reflectors, and wiring)- 37 lbs.
Front fenders - 10 lbs/each

Bill

[svxfiles]

3580
3580 lb car
- 23 lb drivers seat swap
- 13 lb front bumper exchange
- 20 lb rear bumper reengineer
- 14 lb lighter wheels (16.5 ea)
- 33 lb spare tire, jack and tools
- 8 lb trunk carpet + cardboard
- 39 lb exhaust system
+220 lb driver
+ 35 lb gas
3685 lb car

The stock headers weigh 18 lbs, the pipe from the headers to the muffler weighs 50 lbs, the muffler weighs 35 lbs, 103 lbs total. My system, from the home made headers, cherry bomb, 3” tubing + afterburner + polished tip weigh 64lbs. 39 lbs savings
So far 150 lb savings.
Note; 4 lb savings on underdrive pulley offset by added weight of adjustable FPR
I cut out the bracing from under the hood, 11 lbs.(the hood was a spare) Not recommended for the street.
Took off the iron bracket for the ac belt adjuster, 3 lbs.
Note, if the complete front bumper support was removed, it would be a 26 lb loss.















What size are your boots?