Diff ratio with CD box

[SKYMAGGOT]

Looking to swap in a cd009, with the current diff the speed in gears will be lower than with the 5 speed, not sure whether the car would accelerate faster with that setup.

This is roughly what the gear speeds would be, anyone run a cd with a 4.3 diff?

Running a 25 around 400kw.

[GTSBoy]

Even with a 25 5 speed the 4.11 ratio is too bloody short as it is. Turbo (25, not 20) Skylines should have come from the factory with a 3.7 diff anyway.

Back in the 80s, the first rule of adding a turbo to any car was to also add a taller diff - to make use of the torque.

[Dose Pipe Sutututu]

CD009 with a 4.3 diff is just silly, even with a 4.11 diff it's just silly.

I would be finding a S15 diff at 3.69 for the CD009 OR a S15 Auto diff at 3.9

[SKYMAGGOT]

People have used lower ratio's with a cd, there's someone on here with a 4.3 but is yet to run it.

Be a trade off but would possibly make third gear more useable at lower speeds

[Dose Pipe Sutututu]

You'll be cycling gears like a mad man, like a truck.

For a 400kW setup (as you've indicated) I would say a 4.3 with a CD009 is a terrible idea.

[SKYMAGGOT]

Yeah didn't seem ideal looking at the rough calculations but thought someone may have tried it, have a lsd I'd rather not swap centres as was a bit hard to set it up last time

[Butters]

I am running a getrag with 4.11s . Really like it for a street car, as a race car i'd be changing  out to 3.7. 

 4.3 I think is going to far unless you are building a motorkhana car.

[SKYMAGGOT]

Did seem like you'd be going through gears a lot but rolls start at 40km so would have more revs on & around 80km third gear would be better with more revs on, may end up slower for drags with an extra shift though

[Kinkstaah]

If the CD009 had a 7th gear it'd be perfect.

Still perfect for track use, kinda if you want to max out top gear on the track. That said with that kind of power to do that you're effectively got no use for 1st.

What you want is the shorter middle gears with an acceptably long first.

BRB I am going to hug my T56 Magnum some more.

[SKYMAGGOT]

Yeah slightly less top speed in 6th at .794 vs the .759 for the 5 speed, looks like give & take, might be good at some points & crap at others lol, yeah longer 1st & shorter middles like a lot of bikes do it be good

No hugs for the cd at this point