I did a "few" modifications on my track toy in the last 3 years and I am experiencing the fact that harder, more complex and more expensive is not always better if you cannot set the whole thing together. To summarize the mods :
- a lot of weigh savings, which mean a (very) light front end
- 215/615R17 & 260/640R18 Hankook F200 slick tires, on 8x17 ET40 % 9.5x18 ET30
- OS Giken LSD
- KW Clubsport coilovers
- Full metallic / spherical bushings front & rear including non-compliance pivot clamps
- Dali front and rear race sway bars
- Type R front reinforcement bars
- Stoptech ST40 big brake kit
- front home made undertray and spliter
- APR GTC-500 wing (set pretty flat)
The last mods which I think I did not take the benefit they should give are :
- the KW Clubsport that replaced old Tein Flex (not even the "mono")
- the metallic / spherical bushings
My alignment specs remained almost the same. Camber 3.30 ° front / 3.00 ° rear. Toe - 1mm front / + 3 mm rear. Caster around 8 °.
I had the front sway on the middle hole and the rear at the softest hole. As I encountered a bit of understeer at the exit (full gas) of fast corners, I set the front sway to the softest too.
Over all feeling :
- I did not totally eliminate the understeer at fast corner exit with full gas but it is better. I plan a Type R front hood to give some downforce (or eliminate lift) to counteract this.
- The front end is strong. I mean, I never feel the front loosing grip even when tailbraking in a downhill.
- I am more afraid of loosing the rear in this situation. I had one or two situation where it lost grip but I could react.
- The front tires still have a bit (5 mm) of unworn surface at the outside edge.
My analysis :
- I feel that I can use more of the front end by tail braking more. I feel that I can get benefit of the 5 mm unworn outside edges of the front tires and to do this I can tailbrake more agressively. For this reason, I am not into softening the front (sway or dampers) as I did it already with one hole on the sway or reduce the camber (3.30° seems right with slicks and the wear is ok). Nor stiffening it as I feel I can extract more of the current setting (spare outside edge of tires) and I would not stiffen a front end that is already so light (no beam, light battery, no spare tires, no front headlights, no AC condensers, no interior, ...).
- It seems that going "stiffer" / less compliant with the spherical bushings and the Clubsport on a very light car was perhaps not a direct benefit without other changes. The old Tein Flex I had had perhaps a bit harder springs (10/12 vs 8/8) but the damping on the Clubsport is a lot lot stronger. You feel it by trying to move the car up and down by hand that it is night and day difference. If on the front, I feel I can take advantage of this increase stiffeness after just reducing the front sway one hole, I am asking myself if the increased stiffeness on the rear is a bit too much and the more floppy rear induced by the Tein flex was helping a bit.
What do you think of the following changes ?
- replace the rear Dali track sway by the stock one.
- perhaps less rebound rear ?
- softening a bit the compression front to well compress the outside tire as the front end is very light ?
Thanks a lot for your inputs.
- a lot of weigh savings, which mean a (very) light front end
- 215/615R17 & 260/640R18 Hankook F200 slick tires, on 8x17 ET40 % 9.5x18 ET30
- OS Giken LSD
- KW Clubsport coilovers
- Full metallic / spherical bushings front & rear including non-compliance pivot clamps
- Dali front and rear race sway bars
- Type R front reinforcement bars
- Stoptech ST40 big brake kit
- front home made undertray and spliter
- APR GTC-500 wing (set pretty flat)
The last mods which I think I did not take the benefit they should give are :
- the KW Clubsport that replaced old Tein Flex (not even the "mono")
- the metallic / spherical bushings
My alignment specs remained almost the same. Camber 3.30 ° front / 3.00 ° rear. Toe - 1mm front / + 3 mm rear. Caster around 8 °.
I had the front sway on the middle hole and the rear at the softest hole. As I encountered a bit of understeer at the exit (full gas) of fast corners, I set the front sway to the softest too.
Over all feeling :
- I did not totally eliminate the understeer at fast corner exit with full gas but it is better. I plan a Type R front hood to give some downforce (or eliminate lift) to counteract this.
- The front end is strong. I mean, I never feel the front loosing grip even when tailbraking in a downhill.
- I am more afraid of loosing the rear in this situation. I had one or two situation where it lost grip but I could react.
- The front tires still have a bit (5 mm) of unworn surface at the outside edge.
My analysis :
- I feel that I can use more of the front end by tail braking more. I feel that I can get benefit of the 5 mm unworn outside edges of the front tires and to do this I can tailbrake more agressively. For this reason, I am not into softening the front (sway or dampers) as I did it already with one hole on the sway or reduce the camber (3.30° seems right with slicks and the wear is ok). Nor stiffening it as I feel I can extract more of the current setting (spare outside edge of tires) and I would not stiffen a front end that is already so light (no beam, light battery, no spare tires, no front headlights, no AC condensers, no interior, ...).
- It seems that going "stiffer" / less compliant with the spherical bushings and the Clubsport on a very light car was perhaps not a direct benefit without other changes. The old Tein Flex I had had perhaps a bit harder springs (10/12 vs 8/8) but the damping on the Clubsport is a lot lot stronger. You feel it by trying to move the car up and down by hand that it is night and day difference. If on the front, I feel I can take advantage of this increase stiffeness after just reducing the front sway one hole, I am asking myself if the increased stiffeness on the rear is a bit too much and the more floppy rear induced by the Tein flex was helping a bit.
What do you think of the following changes ?
- replace the rear Dali track sway by the stock one.
- perhaps less rebound rear ?
- softening a bit the compression front to well compress the outside tire as the front end is very light ?
Thanks a lot for your inputs.
