diff and dropgear combo advise
Turbo Mini Forums

hy.

finally got it together to continue the turbo build. now... i have slowly been buying parts that i need and dont need but wanted...

all that now leaves me with a choice for drops and final drive.

i can go with standard drops and a 3.44 or 3.11 final drive or straight cut drops 1.045/1 with the 3.11 diff.

what would be your advise and why?

greets.

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

I guess what sort of use and rev range do you have?
I run standard A series drops with the mini spares remote SCCR gear set and a 3.76FD on a 165/70 10. It then the car runs to 8300rpm so sitting on the motorway at 4000rpm wouldn’t bother me.

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

the engine isnt run yet. so rev range no idea. its running on 12 inch wheels standard ratio gearbox.

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

i'd just go for the 1:1 incas e there is any difference in backlash with the 1.045 ratio drops, the .045 only drops the the speed by 3mph at 100mph anyway.

my tought is that a 3.44 might be a bit short and the 3.11 bit long. as i calculated that with the 1.045 and the 3.11 diff would make 3.25. right in the midle of it. so small roads no problem and highway without rushing it.

or am i seeing this wrong?

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

no thats a fair point, although is a 3.2 diff an option?,

what gear kit are you running? if its std helical i doubt youd find the 3.1 too long, admittidly 3.1 can be tall with a s/c set in 1st and 2nd , but 4th is nice for cruising at about 4k.



https://www.calverst.com/technical-info/gea...ing-drop-gears/

I'm in the Helical drops, clubman gearset, 3.2 FD and 10 inch wheels camp. I found this was a good all-rounder.

I could even be tempted by a 3.44 as I don't do many miles!

If something is worth doing, it's worth doing half of.

i meant to mention, if you keep to 1:1 then if the drops get to much you can swap back to helicals without affecting the gearing.

my gearbox is standard helical. the differential is standard to. ( option for a standard 3.44 of standard 3.11) i had a 3.11 in a na 1275 and found it was long ( 12 inch wheels) did about 3800 rpm at 120 km/h
i tought calculating 3.11*1.045 would make 3.25 ( or same as it would aqtualy be a 3.25 or does that straight cut drop gear set affect the drive different then just that?

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

This all depends on what you are using the car for.
I Have standard drops SCCR gearset and 13”wheels and I thought the 3.44 in theory sounded great being able to use the entire gearbox to its potential. Using the entire rev range in all 4 gears on the twisties. Then I got it on the road which was fantastic and until I did a 300mile round trip to pick up some new bits. Sat on a motorway at 70mph at 4K+ revs for an hour and a half drove me insane. I couldn’t even hear my stereo.
I Immediately swapped it for a 2.9 which makes it drive much more like a proper car with much more feel for the added Torque and 100% better for 90% of the driving I actually use the car for.
Alternatively if I was going anywhere near a track (which I’m not) I would have a completely different opinion.
3.11 sounds like a good compromise though.

the car isnt really 100% legal in our laws so use will be track days and occasional runs.

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018