GR Yaris Tarmac Rally Build

RallySlagz

RallySlagz

Fascinated Member
Jan 20, 2025
21
84
13
Ingleton
www.rallyslagz.co.uk
I'm converting my GR Yaris in to a true tarmac rally car. So I've been using another forum, but will start posting here also. Bar the welding of the cage, I've completed all the work myself.


This is my latest photo, showing where the car is up to. At the weekend I got the rear differential out ready for my Cusco 2way LSD to go in. I'm waiting on a few parts from Japan to arrive, but I'm very close to its first full shakedown!

gr 5.webp



Big travel suspension from Finland with a true hydraulic bottom out. This thing will be getting jumped!


gr 3.webp
gr 9.webp

Full FIA cage with seat rails, jacking pins, strut top x brace and subframe supports.

If this sort of thing interest you, let me know and I will keep you updated with the build.
 
Last edited:
  • Like
  • Love
Reactions: Wildcat, Chris_P_Bacon, Onehp and 20 others
Nice build! Where about in the Country are you? I'm in Ecurie Royal Oak club. Would love to see this out on stage!
 
GReeni said:
Nice build! Where about in the Country are you? I'm in Ecurie Royal Oak club. Would love to see this out on stage!
Click to expand...
I'm near Ingleton, North Yorkshire. So your a little south of me but not a million miles. I'm enjoying the project but itching to get out in this thing. Its been off the road over a year now but is very close! Lots to learn once up and running as im on my own, no driver supports at all left in the vehicle.
 
This is the Bigem suspension shown off in all its glory. 55mm up front, true coilover on the rear. I've set the car up about 30mm over stock. Everything wound off initially ready for testing. I like a car with a bit of movement, so will add compression in increments. The engineering and quality are superb, so I'm hoping the feel matches this on the road this.

The front top mount is mounted as per a mk2 GR. 3 triangulated bolts, not one central bolt. Its a simple modification with a drill!


SUS.webp
 
  • Like
  • Love
Reactions: Wildcat, Onehp, sha256 and 9 others
RallySlagz said:
This is the Bigem suspension shown off in all its glory. 55mm up front, true coilover on the rear. I've set the car up about 30mm over stock. Everything wound off initially ready for testing. I like a car with a bit of movement, so will add compression in increments. The engineering and quality are superb, so I'm hoping the feel matches this on the road this.

The front top mount is mounted as per a mk2 GR. 3 triangulated bolts, not one central bolt. Its a simple modification with a drill!


View attachment 33762
Click to expand...
Are these the snow/gravel type? Are they softer than the stock suspension?
 
I've opted for a tarmac set up. So a stiffer spring than gravel, though the damper length is the same as is travel (gravel vs tarmac). As you can see its a lot more than stock, though from the mild testing I've done its hard to compare stiffness. You just run a lot more sag, otherwise the front end would be sky high. I'm hoping for it to be a bit softer than stock, with much more compression and ramp up at the bottom end. To help this I've opted for the hydraulic bottom out, over simple piece of rubber being used. I am planning to jump the car, and wanted as close to the cushioned landings you see from WRC cars, though I wont be flying 20ft high

The rear is limited by the suspension arms on travel, though for gravel you can run subframe spacers. I'm also starting out with no anti roll bars, thus putting all of the load through the springs.
 
  • Like
  • Love
Reactions: GRandemakina, Michael Knight, TheManWithTheStick and 1 other person
RallySlagz said:
This is the Bigem suspension shown off in all its glory. 55mm up front, true coilover on the rear. I've set the car up about 30mm over stock. Everything wound off initially ready for testing. I like a car with a bit of movement, so will add compression in increments. The engineering and quality are superb, so I'm hoping the feel matches this on the road this.

The front top mount is mounted as per a mk2 GR. 3 triangulated bolts, not one central bolt. Its a simple modification with a drill!


View attachment 33762
Click to expand...
Forgive my ignorance; how do the rear coilovers fit to the car? Just through the shock absorber mounting points? Any structural mods/strengthening required?

Another North Yorkshire lad here! 👍🏻
 
GRavy_Baby said:
Forgive my ignorance; how do the rear coilovers fit to the car? Just through the shock absorber mounting points? Any structural mods/strengthening required?

Another North Yorkshire lad here! 👍🏻
Click to expand...
So there are 2 bolts at the top that hold the oem damper onto the chassis (top of rear wheel arch). You utilize these, and with a small diameter spring the coil over fits in its place. The original spring perch is then not used under the boot floor, allowing you to change out the lower wishbone that holds the other end of the spring. Thus you can change this wishbone to something stiffer (like a threaded control arm) with better adjustability for toe (will hold its setting better than the oem eccentric bolt on the subframe).

Yes, all the rear suspension load is then going through the top of the damper mount in the wheel arch. You could probably get away with a coilover for most driving, but it should really be reinforced. My FIA cage has a cylindrical tube that goes down internally to join the top of the rear suspension mounts to the cage (middle left of the photo).

Hope that answers your question ok.

11.webp
 
  • Like
  • Love
Reactions: Wildcat, Onehp, Michael Knight and 5 others
RallySlagz said:
So there are 2 bolts at the top that hold the oem damper onto the chassis (top of rear wheel arch). You utilize these, and with a small diameter spring the coil over fits in its place. The original spring perch is then not used under the boot floor, allowing you to change out the lower wishbone that holds the other end of the spring. Thus you can change this wishbone to something stiffer (like a threaded control arm) with better adjustability for toe (will hold its setting better than the oem eccentric bolt on the subframe).

Yes, all the rear suspension load is then going through the top of the damper mount in the wheel arch. You could probably get away with a coilover for most driving, but it should really be reinforced. My FIA cage has a cylindrical tube that goes down internally to join the top of the rear suspension mounts to the cage (middle left of the photo).

Hope that answers your question ok.

View attachment 33766
Click to expand...
Wow! Awesome 🤩
 
  • Like
Reactions: RallySlagz
Great project! Can’t wait to see the final build! Any estimates what the final weight will be?
 
hey RallySlagz... I work for aFe power and I'm putting together a promotional calendar that we give away at shows etc.
we wanted to feature a GR Yaris.. can I use a pic of your project? .. I can have the company send you some calendars if so.

this is largely a promo item. while we do offer them for sale on our site.. we don't normally get any orders for them.. the majority of them will be given away at the 2025 SEMA show. Let me know.. here's a link to our website.

afepower.com
 
  • Like
Reactions: RallySlagz
jamie said:
hey RallySlagz... I work for aFe power and I'm putting together a promotional calendar that we give away at shows etc.
we wanted to feature a GR Yaris.. can I use a pic of your project? .. I can have the company send you some calendars if so.

this is largely a promo item. while we do offer them for sale on our site.. we don't normally get any orders for them.. the majority of them will be given away at the 2025 SEMA show. Let me know.. here's a link to our website.

afepower.com
Click to expand...
Hey Jamie. Sorry im a bit late, i have just seen your post. More than happy for you to use a picture at any point. If i can see the result id appreciate it.
 
So the car was out and about for some photos the other day with a friend. Its driving well and is such a different experience to any sports car I've driven. The feel of the brakes, the roll, the brutal noises. Its all great fun!

Latest project is mounting the JDM light pod. This will be a big help now we have the early dark nights. I cant wait to see it out in the wild with this pod on. Really gives me old WRC vibes...
 
  • Like
Reactions: RichM
What kind of lower front arms are you using to get that much droop? Seem extended?

Nice build! Where are you gonna use it, for fun or actually planning to enter rallies with it?
 
Onehp said:
What kind of lower front arms are you using to get that much droop? Seem extended?

Nice build! Where are you gonna use it, for fun or actually planning to enter rallies with it?
Click to expand...
Thanks. For now its just fun as i don't have the funds to compete with the car. Id love to get it on some gravel but more prep needed to protect the chassis. I plan to help others with rally mods from the workshop or by suppling parts.

The front has much longer dampers than stock, about 205mm of travel. Stock arms can accommodate this. I then installed genuine Toyota front knuckles that are installed to some JDM GR's and other models, that move the lower ball joint closer to the center of the hub. This corrects the front lower arms angle to horizontal when the car is sat in its droop. Currently the arms are stock, but i will move to an adjustable arm to allow for increased Caster and Camber adjustment such as Verkline.
 
  • Like
Reactions: GRavy_Baby, Provenjohn, Nixkf and 2 others
You must log in or register to reply here.
Top Bottom
Back