M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Swaps, Turbos, Buildups => Topic started by: Jay-Vee on June 15, 2014, 01:32:34 AM
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Hey guys,
Looking at updating my E30 M40 to an M42 from an E36 and wondering which transmission is best to use?
I've read that the getrag used with the E36 version has better ratios but has issues being installed into the E30 and I’m wanting this to be as straightforward as possible.
Does anyone think it would be worth re-using the old original transmission to avoid any hassles or is it gonna be easier for the swap to just keep the engines and transmissions together?
Cheers.
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Depends what is your goal because E36/E46/E90 have different ratios. If your car is used for town only and you like shifting you can go for E36/E46/E90 transmission with standard rear dif ratio. E36/E46 gearbox swap needs les modificamodificationtions. E36 m3 6spd good to go if you could find one. E90 6spd gearbox from 4 bangers needs special clutch disc and driveshaft modification.
At the moment I am driving E36 5spd with 3,64 and with 225/45R17 tires my max speed is around 210km/h. 150km/h is ~5000rpm. I realy want to swap to 6spd but do not have time for this. Realy like car performance on autobahns :)
In my E30 there was 3,9 rear dif and E36 gearbox and liked it!
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Thanks for the info mate, well my goal is for the swap to be as straightforward as possible as I dont have a hell of alot of mechanical experience.
Would it be more common to leave the transmissions attached when pulling it out and dropping it back in?
That sounds like it would be easier, but I'm trying to avoid hassle if the E36 trans has issues being positioned in the E30.
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E36 gearbox from 6 cylinder swap is easy. You will have to swap some components from E30 gearbox and you will need clutch slave cylinder from E36.
Keep in mind E36 gearbox 5th speed ratio is 1 and E30 is 0,8. Your max speed with E36 gearbox in 5th gear will be like with E30 gearbox in 4th gear.
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Hi Jay Vee
The first thing you need to do is have a look at what you have got.
I believe from your car photo plus it's basically the same as mine when I started is 4.10 diff and getrag 240
So stick you head under the back of your car and look at the diff for a metal tag, it's probably going to say 4.10. Probably, take a look.
Then have a look at the ratios on your getrag 240 already in your car. Listed on this site multiple times.
If your happy with your high rpm at 100-110 km/h of about 3000 from memory and good acceleration all is well stay with what you have got. No new gearbox.
However if you wish to decrease your rpm at highway speeds get another diff 3.91 or 3.7. Med or open case and that depends on how much further you want to go with hp. Anything above 250 hp med case and getrag 260 from the 6 cyl e30s
Cheers Rohan
Pm me if you want to bud!
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Cheers for the advice mate, I'll check mine out and look it up on here.
I'm happy with the acceleration so I might look at keeping the one already there.
Thanks again.
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We have the stock Getrag 240 with a 3.45 LSD. Ours is turbocharged, approx 180 HP. It works well for us on highway and track.
It is easier to change the diff than a gearbox.