F13 vs F15

[hendrix]

Going to be doing an X16XE transplant into my E16SE nova very shortly and was wondering if the F13 will fit the XE?
Also what are the pros and cons of both boxes eg which one would give faster acceleration etc
Cheers

[Stuart]

F13 Cr and F15Cr are bascially the same gearbox. only drawback is the F15 is like a small version of the F20 in that the FD pinon is part of the main shaft, so choice of FD is limited to one or two...

[ashjones]

is the f15 a diesel box. think i had one of them and it crap to wide changed to f13 and was a lot better

[Stuart]

The F15 is not genearlly a diesel box

[Jon_nova1]

the F15 would only be good for taking more power really wouldn't it? rather than some sort of speed improvement?

[Stuart]

imho no power hdnaling difference....

you get a taller 5th gear so slightly improved top speed
FD's for the F15 are 3.74 on the Cr and 4.18 on the WR (but i think the WR's are rare as rocking horse poo)
check the speed ingear bit of my sig site to play about and see which is more preferential..

[SRlew]

the guy i baught my engine off offerd me a choice between the f13cr and the f15 he said the f13cr was better for acceleration so i chose that, i like it

revs are quiet high when at 70 on the motorway tho but meh

[Gunzi]

I thought the figures refered to the torque the boxes can take. ie F10 is 100lb/ft, F15 is 150lb/ft?

The final ddrive ratios are stamped on the side of the box IIRC you can see them thru the n/s wheel arch.

[Stuart]

the F number is sustained toruqe in NM *10, thing is no one knows how long the sustained torque is..... in essence a load of old tosh lol. esp for the newer boxes as the numbers dont mean shizzle. and an F10 can take as much abuse as an F13, which can largely take the same abused as an F15....

[Jon_nova1]

you mean theoretically the F10 can handle a constant torque of 100NM? lol

[ashjones]

the bst combo is f13 cr with the 4.1.8 final drive i got told by some rally dude

[Stuart]

for X ammount of time yes.... but as said no one knows that ammount of time.

and more torque means its life is shortend, but again no one knos exactly at what rate etc. but its a fair assumption to make that an F10 would take 200NM of torque for half the life of it taking 100NM...

the reason a LET kills the F20 so fast is that the surge in torque from the engine is too much for the box, but if the torque curve was linear then it wouldnt kill them as often lol

[Adam]

Some f13's also have the clutch change access panel, which is kind of handy.
Altho its of no use with a x16, as it has a POT fly.

Thats one thing i'd definently do before the engine went in, the clutch.
Unless you know its good.

I have a f15cr,3.74 fd, quite a good box, altho revs are high on the motorway, 70mph is about 3.5ish k in 5th,Lol.