does anyone know what good ratios are,
I am tossing up between a 4.12 (bug box) or a 4.86 (kombi box) ring and pinion.
keeping in mind, I am using a N/A subie motor with a 6500 rev limiter.
what size tyres are you using?
um,
don't know,
what's a good size?
my guards are big enough to go with 8x28" slicks if I want.
is there any way you could fit one of those :"much better "
subi gear boxes.?
Mid eng / sub chassis would be good.
Have you downloaded the Exel Dyno (I think) program from Wes`s site it alows you to change all the variables and tells you what sort of et, revs, etc you may run. Is very helpful for playing around with ratios and tire sizes. http://www.offroadvw.net/bajawes/
yeah probably would, but that's $$$$ and alot of stuffing around,
I am thinking more like the TSR racing cars in the UK.
besides, a standard subie box probably wouldn't have the right ratios for a buggy anyway. So i'd be back to square one.
Alternatively: You do lose some power through the
box But have you considered an Auto.
Its what I want to try.
Build the motor more for torque and trick the
converter... well its worth considering.
mmm, don't want to rebuild the motor just yet, it's only done 100k max and besides an auto is not all that strong, really heavy and, most importantly won't fit into my chassis without major surgery (that I don't want to do), I already figured all that out.
just checking...
-
Have you run this engine with a standard ratio
gearbox.?
It would give some reference for Changes.
Like - do you need a higher 1st..
and thus if this were true , raising first and second
might be heading in the right direction.
Also can you figure out what top speed you expect to
reach at end of 1/4 , because that would determine
the final ratio. For arguments sake : 6500 rpm at 140 mph
crossing the finish line would mean the ratio 4th and diff ratio
and tire circumference can be all calculated.
And then when you find that it goes Faster than what
you figured , you go larger rear Tire Dia..
All sounds so Easy.
I think I'll play with the Dyno program like andy suggested. That ought to give me some good ideas.
Go to
http://www.johnmaherracing.co.uk/
He has a ratio calculator and performance figures for heaps of cc combo's with their g/box ratios, their 1/4 times and 0-100km/h.
Good read.....
Apparently the 3.88 is the strongest....then alot of people run standard 1st and 2nd then bring 3rd a little closer and keep 4 as the overdrive. If
not for street then can change 2nd , 3rd and 4th.
Matt
ta boof