Dave M Posted September 11, 2002 Share Posted September 11, 2002 Does anyone have back to back experience with ACB10 13" and ACB10 15" with wheels of similar weight (4.5kg 3 piece). I am currently running 13" and am considering changing up size and would like some feedback regarding any handling differecnes. I am only concerned about track performance. Dave PRB87 Link to comment Share on other sites More sharing options...
Dave M Posted September 13, 2002 Author Share Posted September 13, 2002 OK, obviously nobody has tried this ☹️. Is there anybody out there that has run the 15" ACB10? It is an expensive exercise for me to change and I want to be fairly sure that the 15" will perform the same as the 13". Thanks Dave PRB87 Link to comment Share on other sites More sharing options...
F355GTS Posted September 15, 2002 Share Posted September 15, 2002 Dave for track everybody recommends and run 13" for much improved handling and feel Why do you want to change to 15"??? Mark Link to comment Share on other sites More sharing options...
Dave M Posted September 15, 2002 Author Share Posted September 15, 2002 Yes, but how do the 13" improve handling if the tyres are the same circumference, tread and compound? I may need to change because of calliper clearance and availablity of 13" over here. ☹️ Edited by - Dave M on 16 Sep 2002 00:09:18 Link to comment Share on other sites More sharing options...
scooby dooby doo Posted September 16, 2002 Share Posted September 16, 2002 a 13" tyre with the same circumferance as a similar 15" tyre is much higher profile so it has more compliance in it. So it will definitely have very different characteristics. I can't explain exactly how/why the differences are but I'd start by considering the amount the contact patch can twist compared to the axis of the tyre - it will be larger on 13s... ah - i seem to have crossed the limit of my knowledge here.... HOOPY R706KGU See you at Cadwell Link to comment Share on other sites More sharing options...
Andy Checkley Posted September 16, 2002 Share Posted September 16, 2002 Ive have never really understood the real world differences between running 15" and 13" wheels/tyres. I currently run the standard 13" split rims with ACB10s on my SLR, however on my previous VVC Seven I ran 15" A032s, and for my style of driving, I think I prefered the way in which the 15" setup worked for me. (This probably says a lot about my driving style). Certainly in track performance terms I cannot drive my SLR much quicker on a track than I could my VVC with 15" wheels and A032s. Link to comment Share on other sites More sharing options...
Dave M Posted September 16, 2002 Author Share Posted September 16, 2002 Hmmm, might be a case of lashing out on the 15" 3 piece rims and trying them with the ACB10s. I already have plenty of data on the 13" so a real comparison could be made. FWIW I run 2 way adjustable Koni shocks and have a range of springs to choose from with adjustable anti-roll bars front and back. I would rather tune the cars handling using these "controlable" devices than rely on tyre sidewalls for compliance. The 15" wheels are proposed for a new project which will be lighter than my existing se7en, so control of the damping will be more important. I don't have any technicial expertise to back these comments up, just my thoughts. Dave PRB87 Link to comment Share on other sites More sharing options...
Peter Carmichael Posted September 17, 2002 Share Posted September 17, 2002 Urk! Suspension is made up of both the tyre characteristics and the spring/damper/rollbar setup. You cannot compensate for one with the other. The tyre takes out higher frequency vibrations while the suspension takes out the lower frequency ones. You need to build a matched system. A stiffer tyre is more suited to a heavier car. Running a low profile (stiff) tyre on a Seven can leave a range of frequencies undamped leading to a certain suddenness of breakaway. If you don't get this, then I guess the tyres are working OK. YMMV Link to comment Share on other sites More sharing options...
Highlander Posted September 17, 2002 Share Posted September 17, 2002 FWIW I would suspect that running 15" rims would increase the unsprung weight, and since your planning a lighter project this would adversely affect it. Also with 13" rims you have a wider choice of tyres including slicks. But what do I know :-) Link to comment Share on other sites More sharing options...
stevefoster Posted September 17, 2002 Share Posted September 17, 2002 I met a chap at Cadwell who was running 15" slicks on his VX race car. The grip was good and he was fast but he said the 15" tyres were much more expensive than 13" ones. I guess the same would be true of ACB10's. /Steve My racing pics, 7 DIY, race prep. Updated often here Hants (North) and Berkshire area club site here Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted September 17, 2002 Share Posted September 17, 2002 Peter, Why does the R300 work so well then? It runs on 15 inch 195 / 45 profile CR500's. I've just fitted a set of these to my car and so far, on the road, they seems pretty good. Less "squidge" on turn in compared to the Bridgstone S-03's (and much more grip - feels like 032R levels of grip although hard to tell on the road)) and they don't tramline as much as ACB's. I wonder if bigger wheels have got a bad press because it usually mean't using crap tyres. Alex Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now