Colloti Gearbox & Wheel Size

[undergroundade]

I am building a competition 130TC for next years Toyo Championship and am getting my hands on a Colloti gearbox with LSD.Can anybody help me on a suggestion for ratios and the best wheel diameter.

Thank you

Adrian

[Julian]

Do you know what sort of speeds you need to attain and where the peak torque range is on your engine? What is your redline for the engine to maintain reliablity throughout the season? Are you planning on a rebuild mid-season?

The select of tyre diameter (gearing) and gearbox ratios is going to come down to letting the engine lay down its best punches where they will make a difference - exiting corners, corner speed (without dropping off cam) and peak speed attainability.

I assume you are not in a position to change ratios between events so your choice is going to be a fairly general one for the season. I also assume that you are tied to using Toyo tires given the title sponsorship of the series.

Given that the above two assumptions are correct then your first step is to look at what tyre sizs are available to you - not all are applicable to the car and wheels you have to hand. If you are buying the wheels then you can to an extent cherry pick from the tyre list but keep in mind that bigger wheels and lower profiles are not necessarily better unless you can afford ultralight alloy or composite wheels.

So please start by filling in the details so we have something to work with.

[Guy Croft]

Try this link, enter diff ratio (default is 3.73) tyre size, gear ratios etc.

http://www.diffsonline.com/techinfo/Gea ... ulator.xls

Thanks to the guy at Diffsonline LLC who wrote it, I just wrote them a thank you note.

GC

[Guy Croft]

You'll all be pleased to know I'm sure that I had a very nice, cordial letter from Dan which said:

I like the way your site is setup and nice to see how many things the ZF LS fit in.
Anytime I can be of help with parts etc, give me a shout.


Dan Fitzgerald

Diffsonline LLC
Building Performance Differentials and Transmissions for Race and Street BMWs
Bavarian Performance Group LLC
Independent BMW Service, Repair, and Performance
1034 Main St
Winchester MA 01890
781.983.2944 Voice
866.593.5692 Fax

Nice to be able to introduce and bring together folk with common interests, isn't it.

GC