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[The Wind Breezes]

Currently running Ventus V12. I made the rear tires totally bald after 3 or 4K miles due to welded diff and hard driving. The plan was to run em down to the cords but I got severe tire damage near the bead due to a nail I was running a 245 / 40 / 18 in the rear and 225 in the front, now I've ordered 4 new 225s to put all around the car, still V12. From what I read it should be no problem putting a 225 on a 8.5 inch wheel.

I mostly drive the car on the street and even with tune and downpipe it has way too much rear grip so hopefully this will make things more interesting. For reference the first thing I do each time I get in the car is hold the DSC button for 3 seconds.

I should get the the tires by Friday and will report on how she handles after I get em installed, which I guess will happen this weekend. Anyone else gone this route?

[brytom]

I see those tires on cars with cheap owners so imagine they're cheaper tires. They're noisy and don't seem to last long.
I went from 225 Sumitomo in the rear (new tires on the car when I got it) to 245 Pilot Super Sport. Those Sumitomo did not grip worth at all, made it a little more fun to drive.

[juld0zer]

I dont think it has too much rear grip if you finished the rears that quickly!

That's not a true square setup if you are stretching them onto an 8.5" rim.

By the sounds of it, you enjoy burning rubber so if less traction is your aim then wouldn't a crap tyre be more cost effective? Just put some cheap Chinese tyres on lol

[The Wind Breezes]

Yes they are very cheap tires! From what I understand it shouldn't be a "stretch" to get the 225 on a 8.5. We'll see.

I'm as interested in seeing what this does for the balance of the car overall than just losing traction. I've run two different compounds F/R before and the balance isn't fun for anything but slides. Same problem with putting cheap shitty tires all the way around. V12 are actually not bad for the money.

[MightyMouseTech]

Wait, welded dif? WTH?

[The Wind Breezes]

Originally Posted by MightyMouseTech

Wait, welded dif? WTH?

I TIG welded the diff myself. Personally I like it better than all but the most expensive LSDs and even then the consistency cannot be beat. I'm quite happy with the results, but of course it changes some handling aspects of the car radically so you need to be an experienced driver and adjust your driving to suit or you will have a bad time. It's freaking awesome in the rain, in the dry, and on gravel, and slightly less awesome but still functional in parking lots.

[infinitekidM2C]

cray...hey that's my parking spot...i'll be there in about 5-10 minutes

[The Wind Breezes]

They're installed, here are my first impressions!!
TLDR; less rear grip, more balance

Took the rear wheels to a Mexican tire shop and got the new tires mounted and balanced for $20 total. Not a bad deal, and they were a lot faster and more professional than the chain stores, plus they let me watch.

Car setup is 35psi front 42 rear 225/40/18 all around. I kept my 245s at high pressure too. The front tires are older, and half worn--haven't mounted the new fronts yet. Camber is within stock limits all around, and the only suspension mods on the car are whiteline inserts in the rear. Went for a little drive with a variety of corners, several 90*, a few "cloverleaf" circles with elevation change, and a high speed on camber left hander that crests a hill. The driving was relaxed, although I did push it mid corner in the cloverleaf and on a few other slower turns. As always, DSC OFF as soon as the car's started.

The handling changed more radically than expected. Amazing what a difference that small change in tire width makes. The "buffer zone" of fresh high treads on new tires is always a pleasant surprise, so that was noticed, but what REALLY caught my attention was the car's new balance. Very noticeable on the cloverleaf which is kind of like a huge undulating skidpad taken at autocross speeds--50 - 55 max. At these speeds you can only tell so much about the car's stability, so it's more telling for mid corner grip and balance. The car is still setup to understeer, but there's noticeably less than before. Whereas my previous driving philosophy was "all the grip's in the rear, drive like it" now there is more balance and the rear is no longer the anchor it was. I'm not sure about straight line grip because I only went WOT in 3rd gear and higher, and on smooth surfaces it held there which is not much surprise.

The car seems like it will be more interesting at high speed for sure--I hesitate to say "dangerous" because that's up to the driver. I will have to investigate the high speed handling on the track, because I don't want to wreck the car probing it on the street. It's already obvious that this new setup demands a more conservative style at high speed as the rear is less stable.

I'm not sure what role if any the very slightly stretched aspect of the rears have in all this. It seems like the carcass would deform less, meaning the rear suspension would handle more of the car's kinetics initially, although with the increased tread height rear vs front it's hard to tell. I'll get the fresh fronts mounted later this week.

[infinitekidM2C]

llantas cabron!

[ShocknAwe]

In for more details and thoughts on the welded diff.

[The Wind Breezes]

Originally Posted by ShocknAwe

In for more details and thoughts on the welded diff.

It's great. There's more understeer on corner entry but it's just another thing to change your driving style around. The car is more sensitive to throttle steering at the limit and responds much more consistently. Slides are WAY more consistent too obviously. The stock e-diff was a PIECE OF SHIT with regard to sliding, it was doable but the lockup was extremely inconsistent and unpredictable. Now it's as consistent and predictable as can be. You will get wheel hop in the wet when sliding with a stock car + welded diff. There is no wheel hop sliding in the dry. Overall the car is a lot more fun wet or dry. I have subframe bushing inserts now which reduced the hop a little but still get some. I might get around to making a diff bracket eventually.

The amount of additional grip over the open diff is pretty surprising. Just imagine all the situations where you would have spun the inside, well, now you don't take that hit as there's 100% lockup all the time.

As far as cons, well, there's wheel hop in parking lots and when making slow tight turns. You also get tire squeal when driving slowly sometimes, but only on certain surfaces. The car takes a lot more throttle to move from a stop if the wheels are at all turned. I guess the wheel is slightly heavier at low speeds too but that's really not noticeable with the power steering. Oh, and FORGET about pushing the car in neutral unless the wheel is totally straight!