Ae71 Vs Ke70 Diff

[BlueKsev]

Hey all i've just picked up an ae71 with a spare diff ( for $100 :dance: ) and i'm going to put the 4ac into my ke70.

 

Well, i have heard the ae71's diff centre's have a 4.1 ratio for auto, and 3.9 for manual can anyone confirm this?

Ke70's have 4.3 for auto, 4.1 for manual.

Are the diff's from the ae71 and ke70 the same? other then the centres of course?

 

Next, the ae71 tailshaft is different is it? I'm guessing the spline off the gearbox arent the same as on a k40 or k50 box.

Reason for this is i want to know how i go around keeping my ke70 diff with the 4.1 ratio for now. Might give me a little more acceleration then the 3.9 ratio.

Could i use rear half ke70 tailshaft, front half ae71?

 

The struts from the ae71 are the same as in a ke70 too aren't they?

 

I have spent a while searching around but haven't found any real answers.

Any information would be appreciated.

 

Cheers, Ben

[flamingheads]

I'll get it started from my hazy memory of this stuff.

 

KE70 & AE71 diffs are not the same. I'm not sure on the ratios.

I believe the AE71 diff will bolt on without any mods but a quick measure will confirm this for you.

 

Next, pretty sure tailshafts are different and not compatible so you'll need the AE71 shaft.

 

Not sure how the struts will go. I think they're compatible but don't take my word.

 

I know the info's all out there somewhere. Hopefully someone will come along and correct my mistakes. Good luck with it

[Ben-89]

True auto ae71s have the 4.11 diffs Made by Borg Warner, this can be identified by the backing plate which can be removed from the rear of the housing. Manuals have the 3.89s. Having done the auto-man conversion Ill tell you the 3.89 diffs arent too bad on take offs while you giving good cruising ability thanks to its low final drive.

 

I wouldnt bother with putting the ke70 diff unless you want really great take off and poorer

top speed. Just to simplify..

 

AE71 AUTO 4.11

AE71 MANUAL 3.89

 

KE70 AUTO 4.31

KE70 MANUAL 4.11

 

Whilst on the topic, if you have an early flat front ke built before 1983 in SE trim it will most likely have an S series (Jap) diff which unbolts from the front as opposed to the rear on the Borg Warner..

 

K40/50 have a different spline shaft compare to the T50, so its probably easier to use an AE71 tailshaft if you have access to a cheap one.

[BlueKsev]

Alright thanks guys :).

Yeah my ke70 is an 83 model and it does have Borg Warner with the bolts on the rear.

Just from the short drive i had in the ae71 taking it home, It has a very noticeable power increase over the 4k. Put your foot down in first and it has no problem spinning the rears. The ksev struggles even if you drop the clutch from stand still. So i thought combine this power with the final drive ratio of the ke70 and i would have adequate performance ;)

I don't mind if the top speed is low. The 4ac is on a 5 speed box as well so shouldnt be revving too high at 110kmh which is as fast as il ever want. I'm stuck on an 80kmh top limit for a year as it is anyway.

 

And yeah i should have everything i need + more. I've got the complete ae71 as well as all these goodies off a spare one. And i'm definately sorted diff wise, i have 2 manual ae71 diffs, 1 reco'd auto ae71 diff, 1 manual ke70 diff and one T series diff with 3.7 ratio + all i need to install it. I'm just trying to pick which one to use haha!

Cheers

[SLO-030]

Spoilt for choice :cool:

[Ben-89]

The ae71s do have that extra grunt on tap if you need it :y: I have been in a mates ae71

with a 4ac, t50 and 4.11 diff and with the 4.11s the revs sit on roughly 3,800 or a tad more. Thats going at 100 as well, my previous 4ac, t50 and 3.89 was sitting on 3,000 or a tad more at 100km so it really sipped the juice.

 

Maybe you could stick with the 3.89 Borgie and keep for events the T series or possibly hunt down some disc brakes and lsd centre while its off the car:y:

[BlueKsev]

Yeah iv got plenty haha i'm pretty sure I'm selling the T series to a mate though. Could always use a bit of extra $$$ and he needs it more then me - he's doing an sr20 conversion

And yeah it definitely seems worth the conversion. I think the 4ac might be a little under-rated.

Oh that is revving a bit high at 100kmh then.. oh il see what its like i can always change it later :)