Gus

Am making the switch from 17 to 18. Received the 18's toady - OZ Alleggerita HTL with Toyo R888 - Frt 235/40/18 and Rear 265/35/18. First thing I noticed was that the R888 are a little taller than the 17 Hoosiers I run Frt dif is a 23.8 dia vs a 25.5 (R888) and the rear is 24.8 vs 25.4 (R888) - widths are very close to being the same in section and tread frt 9.8/8.9 vs 9.6 /9.0 and rear at 10.2/10 vs 10.8/ 10 - tread width is basically the same.
For me it looks like I am going to have to lower the front ( 1 3/4 inch difference). So I need to drop at lease 3/4 inch or more to get back to the level I am was at with the 17's and drop the rear a little 0.3 inch. I know I have this in the rear, but believe I am as low as I can go on the front without changing springs again.
Just wondering for those of you that have made the switch from 17 to 18 - What differences have you run into and what suspension adjustments have you had to make.

sml

why compare back to the 17? was it 100% perfect?

just start from scratch with ride height & alignment.

Gus

Not looking to compare as I know things change - really trying to get input on what others had to change/ or adjusted - so I have an idea of direction to go.

sml

that's a different question .. why not just search for ride height & alignment topics then.

s4magman

Although this has nothing to do with ride height; with the switch to 18s you may also consider the steering rack brace. You have a few options for that brace - original 993, RL'er Peter (chaoscreature), or Rothsport.

jotaking

Does anyone know what the largest wheels you can get on a narrow body c4 without messing about with fenders etc...

I am looking at speedline split rims 18's front 9" and rear 11" will they fit?

TIA

Steve

s4magman

SML and Bill Verburg have many posts on this topic - quite informative ones on the fit of various wheel sizes. NB with the widths you are mentioning is unlikely without rolling or cutting the fender lips. Offsets and camber become critical too.

Gus

9 front and 11 rears are too big - the sectional width of the tire would be too great. Frt at 8 is safe and rear at 9 is safe- 10 very questionable, as the next question is what size tire are you mounting and what would the sectionla width be. Even then (depending on spacers) you will need to roll the inside fender lip up. The stock lip sticks out on the inside and will cut into the tire on hard cornering or major bumps.

swaini

hi jotaking,
i changed over to 18s on a narrow body carrera 2, mine are 9.5 in the rear, messing with the fenders will depend on how u wanna go and tires...

i had to... expensive but worth it.
pirellis have a more contoured round edge, i havent tried them personally as i run continentals. but this was on more than a thread here in rennlist. hope this was helpful.

sml

only if you buy the wrong offset ... 9.5" has heaps of room.

10" is easy and 11" has been achieved.

you missed some important info ... 9.5ET????????????????

swaini

that was the set recommended by fvd germany.

sml

this is incorrect ... 10" is fine with the correct offset & camber even at very low ride heights.

jotaking

The actual sizes are

18x9.0 Front et 40
18x11 Rear et65

The wheels are rh speedlines

Will these fit or would I need to start adjusting fenders etc...

Gus

See recent comments posted -
https://rennlist.com/forums/964-foru...tri-state.html

sml

correct .. that is 10ET40.

10ET44 to 10ET47 is the sweet spot with max neg camber for no mods .

search the threads for the guy with the 11" to find out the perfect camber and offset.