8vtornado 0 Posted March 9, 2009 i was looking to fitting porsche brakes (i started getting the parts) but i have now been thinking about spacing. my wheels will need changing or spacing and im not changing them after spending forever polishing them, so i gotta space em probably about 15mm and do arch work to allow for this. my problem is the way spacing will affect the handling. surely its gonna put all the steering geometry out and corner funny? i love the way the car handles at the mo and if it gets worse itd be a no no to the brakes as i cant reverse the arch work as id space the rear and pull the rears too. i would like some feedback from people who have got wide spacers on their C and preferably with track experience with it to define the real difference in handling. thanks :) Quote Share this post Link to post Share on other sites
8vtornado 0 Posted March 11, 2009 no1? Someone must have 15mm spacers on their c? Thanks Quote Share this post Link to post Share on other sites
luke w 0 Posted March 13, 2009 I've been using 15mm spacers on my Mk2, not really found any problems with them really. There's no wheel wobble at high speed or any real adverse handling issues. I've done 3 trackdays with them without any problems, but I haven't been on track without so can't really say if their's much difference. It does tramline a little more, but thats about it really. Quote Share this post Link to post Share on other sites
Henny 0 Posted March 13, 2009 I use 11mm spacers on my early Corrado G60, but that puts the 40 offset wheels back to 29, which is about right for a 7.5" wheel on a G60... The reason I run these spacers with 40 offset wheels is because the dish on the 40 offset wheels is less than on a 30 offset set of the same wheels (they're a different casting). This means that they'll clear my Brembo brakes easily, but won't change the handling characteristics of the car... On J-DUB (late G60) I ran the same design wheels, only with a 30 offset , again with an 11mm spacer giving a final offset of 19... this didn't seem to screw up the handling any, didn't make it tram line and didn't stop a local motorsport company corner-weighting the car and setting up the tracking/camber properly for me... With the spacers and 30 offset wheels on my early G60, the wheels stuck out from the arches and looked bloody silly... with the 40s, they sit perfectly... I can't see the extra 4mm you're on about making that much difference, but it's all dependant on what the offset and width of the wheels you're running are... Quote Share this post Link to post Share on other sites
8vtornado 0 Posted March 13, 2009 thanks for the replies. well as you seem to not notice adverse handling it should be ok, i dont want to ruin a really good setup, obviously i know the camber and tracking will have to be re-set, thats no probs, i was just thinking about as the wheels turn, the position of them will be different to standard as they are further from the pivot points. my wheels are 17x7.5 borbet C's and i think the offset is 35. so am i right in thinking my offset will become 20 if i use 15mm spacers? my wheels will come out further, i am sourcing some later spec front end stuff at the moment, probably have to flare those a little too. did you space the rears aswell? thanks Quote Share this post Link to post Share on other sites
Henny 0 Posted March 13, 2009 ooh, ooh, ooh! Borbet Cs? I can answer this one then! :lol: :clap: :clap: :clap: The wheels I was on about in my earlier post are 7.5x16 Borbet Cs! (I've been called a Borbet C whore in the past... :oops: ) Right, the 35 offset Borbet C is a less dished casting than the 30 offset ones... at least, this is true for the 16" ones, and I'm reasonably sure this is also true for the 17" versions... This means that the clearance on them is much better than the 30 offset ones which have a deeper dish to the spokes so they hit the calipers! I actually have a spare 35 offset 16" wheel which I've had a 6mm spacer made for so I can use it as a spare wheel without anyone being able to tell the difference (unless you look really closely at the spacer!)... The best way to tell what the dish shape is on your wheels is to have a look on the rim for the casting number... it'll be something like C75730 or similar... That means: Borbet type C 7.5 inch width, 17 inch diameter, 30mm offset casting style... Unless the brakes you're putting on a HUUUUAAAGGGEEEE, you will probably be able to get away with a 10mm spacer to clear your new brakes... at least, with a 10mm spacer they cleared my 305mm 4 pot Seat Ibiza Cupra Brembos in both 30 and 40 offset 16" versions... I went with 11mm when I had the new spacers made for the 40 offset wheels, just to give me an extra 1mm of clearance on the brakes... they were somewhat close before, but not dangerously so, but as I was having new ones made anyway, I thought why not add in a mm clearance?!? :lol: On J-Dub, I only spaced the front wheels... on H-YYU I've spaced all 4 wheels to keep the same offset all around... I happen to have a set of 10mm, custom made, hub-centric spacers which were made specifically for Borbet C wheels (they replace the spiggot ring too!) going spare at the moment... Quote Share this post Link to post Share on other sites
StuartFZR400 0 Posted March 13, 2009 Good ol' Henny - glad you're still here chap. Tit bit on tramlining, it can be cause by a few things and I dont think 1cm offset less will make much diff. It can be more down to things like: tyre pressure, tyre cast shape/brand and tyre size. Also a bad camber will mean you're running on the edge (inner or outer) of the tyre and thus tramming will be real bad. The only note on spacers - as you've established they should be safe, considering people trackday them - would be that you need to ensure your wheel bolts still go into some thread the same amount - dont leave yu self short. Get a piccy up soon. Quote Share this post Link to post Share on other sites
8vtornado 0 Posted March 13, 2009 cool thanks, number on the wheels is 75730 so must be 30mm offset. The brakes im using are porsche 4pots from a boxter with the 305 ibiza discs. Ill have to measure how much space i need to create when ive got the brackets made up, how much wud u want for the spacers? Is it a set of 2or 4? As ur a borbet c whore ill post up a pic later of mine, i think ul like em! I have some 10mm longer bolts, dont worry ill be safe, hubcentric and longer bolts! Thanks Quote Share this post Link to post Share on other sites
Henny 0 Posted March 13, 2009 the last 2 numbers (30 in your case) are the casting number, that's not necessarily the same as the offset! The 40 offset end with 35... they cast 'em with a much larger center than needed and then machined them down to the offset required... IIRC, 40 was the actual cast offset for the 35s, and they could then do any offset between 40 and 35 by machining off material from the mounting face... 35 was the actual offset for the 30 cast, and from that they could make anything from 35 to 30... etc,etc, etc.... 8) You could still have 35 offset wheels, but on a "30" casting which would give you a slightly deeper dish than a 35 offset on a "35" casting... Does that make sense? It's been a long day... ;) :lol: I'll check I've still got the adaptors (I'm sure I have, but it's been a while!)... Oh, and I've edited my post before as I got the numbers the wrong way around... :) Quote Share this post Link to post Share on other sites
8vtornado 0 Posted March 13, 2009 ul love this or hate this: to this: theyre polished (took many many hours to do!!!) with metallic grey inner bits. but they flip to grey spec at most angles: i want to lower it a bit more, its got arch gap, which isnt good! and its gotta go wider too to enable the brakes to be fitted which are sitting under my bed atm!!! so shud look good. and stop well!!! how are you finding the 305s? isnt the offset stamped on the inside of the wheel? Quote Share this post Link to post Share on other sites
Henny 0 Posted March 16, 2009 the wheels I've currently got on my Grey G60 were polished when I got them from Germany... I liked 'em, but had them refurbished back to standard silver powdercoat as they're then much, much easier to take care of and I'm a real lazy get at times! :lol: Those look nice with the centers grey and the faces polished... not seen a set done like that, and they suit it nicely... Personally, I think your C sits almost perfectly... I definitely wouldn't go lower as you'll screw up the handling and ride quality... The 305s are awesome... Jim's been witness to just how silly they are when I took him out at Bruntingthorpe and did a brake test from about 110mph to stand still... I'm glad we were both wearing seatbelts! :lol: The offset is, indeed, stamped on the inside of one of the spokes normally... Are you sure you're going to need to space the wheels to fit the brakes? There looks to be loads of clearance there... Quote Share this post Link to post Share on other sites
8vtornado 0 Posted March 16, 2009 i havent made a proper set of brackets yet but made a mock up one and im pretty sure itd need some pretty big spacers. Did u make the brackets or were u lucky enough to get some ibiza ones? Im havin a little trouble atm with money to buy the stuff and with modifying the cad drawing for the brackets atm so im not sure when ill be getting them on, which is a shame cos the pads on my old brakes are getting low! Thanks for the compliments. I think the car wud look much better 10 - 15mm lower, if it makes it handle rubbish tho ill wind it bal up, its on koni coilies =D Quote Share this post Link to post Share on other sites
Henny 0 Posted March 17, 2009 the 305s I have are the full kit, so the proper mounting bracket and brand new calipers from Seat back before they got silly with the prices... 8) Quote Share this post Link to post Share on other sites
fla 9 Posted November 2, 2009 slightly away from the core of this thread, but if you use normal spacers (ie non hubcentric) on the front wheels how would you get teh wheels balanced? I would assume that this would mess up the balance, no? Quote Share this post Link to post Share on other sites
