One of the post made me put my thoughts deep in to this subject... Particularly relating to the 705.
Johan and some of you guys have asked how did the front upper arm mod felt and putting one and one together, I came to this conclusion...
I've not tested my car for some time (1 week is long enough
). On the intention to get more steering and getting even tire wear front and rear, I embarked on using softer front tires than the rear and the car will still work OK with no oversteer. I have also used a 4.5 mm split between the front and rear tires (using 18T side pulley, 22T brake pulley and 47T rear diff pulley). This should also make for more steering when running smaller front tires. In my incomplete testings, I have not used equal front and rear tire shore. My apologies for not bringing this up earlier but I think the front upper arm mod increases the roll center thus making the front part roll less. This means less steering.
My guess this is why Michael Salven (and perhaps Ralph Burch who I'm not sure if he did the front upper arm mod) had to take off the front sway bar to get enough steering.
I would think that on high grip tracks, this mod would prevent traction rolling to a certain extent. If Ralph actually did the mod, he probably set the car for way too much steering as it was reported that his car flipped a few times.
Going further, I think I may have overdone things a little. I think my front roll center is too high so much so I do not get enough steering. This is because using smaller front tires by running the split already increases the front roll center. Doing the front upper arm mod will increase the front roll center further
On my Impulse, I remembered that I had lots of steering WITHOUT the front upper arm mod but only running with 4.5 mm split front and rear tires. It felt very nice. I think I'll run equal front and rear tires with the upper front arm mod and see how it goes.