Turboed 1.6L diff upgrade?

[Lucky_Luke]

My first post!! Hi guys, Ive been watching this forum for ages and it seems to be full of MX nutters like myself, and Í need a little advice Im hoping some of you guys can help with.
Ive had an 1990 mx for about 4years and finally installed an AVO turbo kit, and am running 140kw atw's.

Its absolutely insane, but as I knew and have been reading my little 1.6L diff is making funny noises and needs to be upgraded.

I also have a sprung button Xtreme 4puck clutch and is pretty brutal on the diff, and so am wondering on whether a mazdaspeed / cusco/ guru upgrades for the 1.6L diff are worth it in being able to take the 140kw power and some punishment? and which would be best for street use?
otherwise how hard is it to swap in a 1.8L diff ,or rx7 diff?
Im sure someones done this? whats involved in this? $$$?

Any help or advice would be great!
Luke.

[Craig]

Get a 4.1 ratio'd Torsen from a 1.8 and you'll need the tailshaft and both the half/drive shafts too. Plenty of 1.6's have done this conversion and with your turbo you'd be a prime candidate as the 1.6 diffs are a tad on the weak side, breaking even in standard cars. Send MX5_DriftFury a PM (I've bought 2 off him previously), or try www.mx5factory.com.au or www.mx5mania.com.au

Craig

[Juffa]

Like Craig said, go the 1.8 diff. I paid around $1800 for a 1.8 torsen lsd. Much stronger than a 1.6 diff.

J

[Sean]

Sounds like you have a similar setup to me.
AVO based turbo kit.
Extreme 4 puck clutch.
Broke a bunch of 1.6 diffs before even going turbo.

Have upgraded to the 1.8 diff and never looked back. The car makes about 240hp on the street and was daily dríven until the start of this year. It's also been drag raced at close to 10 race days/test and tune days with considerably more power and the diff is still hanging in there.

We've recently added launch control which puts considerable strain on teh drivetrain off the line, and still no problems, it's *just* started to get noisey.

[Lucky_Luke]

Cheers guys, thanks for the replies already! its only been like 2hours!

Yeah after driving the naturally aspirated mx for so long i think i was a little \"trigger\" happy on my first drive with the power and now the rear isnt so happy.

Sounds like the complete 1.8L diff upgrade is more popular so far.. and its good to see you guys are getting good use out of them.

Im a tad bit uneducated on the drivetrain side of things.. as to what years came with which diffs.
Iam told all aussie delivered 1.6L had standard diffs and the import 1.6L have LSD's, is this same for the 1.8L NA's running gear?I just dont know which years came with torsens or not or whether they all did either...

Anyone know which year mx would have a suitable donor 1.8L diff? for a 1990 . Does the whole diff housing would have to be swapped as well ??
or can the 1.8L differential fit in a 1.6L housing?

Craig which year mx does that 4.1 ratio 1.8L torsen come from?

Thanks again guys! keep it coming!
Luke.

[Lucky_Luke]

Cheers guys, thanks for the replies already! its only been like 2hours!

Yeah after driving the naturally aspirated mx for so long i think i was a little \"trigger\" happy on my first drive with the power and now the rear isnt so happy.

Sounds like the complete 1.8L diff upgrade is more popular so far.. and its good to see you guys are getting good use out of them.

Im a tad bit uneducated on the drivetrain side of things.. as to what years came with which diffs.
Iam told all aussie delivered 1.6L had standard diffs and the import 1.6L have LSD's, is this same for the 1.8L NA's running gear?I just dont know which years came with torsens or not or whether they all did either...

Anyone know which year mx would have a suitable donor 1.8L diff? for a 1990 . Does the whole diff housing would have to be swapped as well ??
or can the 1.8L differential fit in a 1.6L housing?

Craig which year mx does that 4.1 ratio 1.8L torsen come from?

Thanks again guys! keep it coming!
Luke.

[Lucky_Luke]

Cheers guys, thanks for the replies already! its only been like 2hours!

Yeah after driving the naturally aspirated mx for so long i think i was a little \"trigger\" happy on my first drive with the power and now the rear isnt so happy.

Sounds like the complete 1.8L diff upgrade is more popular so far.. and its good to see you guys are getting good use out of them.

Im a tad bit uneducated on the drivetrain side of things.. as to what years came with which diffs.
Iam told all aussie delivered 1.6L had standard diffs and the import 1.6L have LSD's, is this same for the 1.8L NA's running gear?I just dont know which years came with torsens or not or whether they all did either...

Anyone know which year mx would have a suitable donor 1.8L diff? for a 1990 . Does the whole diff housing would have to be swapped as well ??
or can the 1.8L differential fit in a 1.6L housing?

Craig which year mx does that 4.1 ratio 1.8L torsen come from?

Thanks again guys! keep it coming!
Luke.

[Craig]

Luke,

You need to turf the entire 1.6 diff, tailshaft and half/drive shafts and go 1.8 for the lot. The only NA's here to get the LSD's in NA format were the Clubmans which run a 4.1 ratio compared to the 1.6's 4.3, although the on road difference is negliable between the two. The Clubmans are a 1.8 Sports version FYI with hard suspension and no power steer.

Stay away from the 1.6 LSD's as they aren't much better than the normal 1.6's, and the 1.8's offer way more strength.

A 4.1 ratio may come from a 93-2000 jap import and they all bolt in OK being the same shape. There are other ratio's out there, I've got a 3.636 for my car as it's a 6 speeder for instance, with some 3.9's floating around as well. Only way to tell is to open them and to count the teeth and have a look see that it's actually an LSD too as you can't overly tell looking at them externally.

Craig

[Juffa]

Cheers guys, thanks for the replies already! its only been like 2hours!

Iam told all aussie delivered 1.6L had standard diffs and the import 1.6L have LSD's, is this same for the 1.8L NA's running gear?I just dont know which years came with torsens or not or whether they all did either...

Anyone know which year mx would have a suitable donor 1.8L diff? for a 1990 . Does the whole diff housing would have to be swapped as well ??
or can the 1.8L differential fit in a 1.6L housing?

Craig which year mx does that 4.1 ratio 1.8L torsen come from?

Thanks again guys! keep it coming!
Luke.

Even if you were to get a 1.6l LSD it would eventually break as they are not as robust as the 1.8l
You have two choices when upgrading to the 1.8 diff. Get a non-LSD diff and upgrade the centre to LSD at a later date, or buy a LSD first up. I'm not sure of the price difference, but I would suggest it will be less painful in the long run to go the 1.8 LSD up front.
The diff housing, drive shafts and nut/bolts to attach the drive shaft to the diff from a donor 1.8 all need to installed for the upgrade.

Not sure what year the 4.1 torsen first appeared. Mine is from a 2000 model. With most cars the later the model, the lower the Km...but as we know that doesn't always apply to MX-5s......I know MX-5s older than mine with less Km.

J

[Matty]

The 4.1/ 1.8l diff first appeared in '94.
You can always buy an open diff and fit a Torsen later...

[Craig]

do all the 1.8 na clubmans come with the torsen lsd from factory? what about the 94+ na limited edition models?

Only the NA 1.8 Clubmans, 10AE and SE got them factory fitted in Oz

[SuperMazdaKart]

what are the symptoms of a dying 1.6 diff? i think mines is just about done is making creaking noises from taking off at a stop. mostly in first gear but sometimes also a little bit in 2nd gear. the noise rather reminds me of a busted CV joint in a FWD.

how long it take to get one of these 1.8 torsens interstate couriered/freighted etc from Driftfury?

[Moggy]

Luke,

The only NA's here to get the LSD's in NA format were the Clubmans which run a 4.1 ratio compared to the 1.6's 4.3, although the on road difference is negliable between the two.

Craig

Didn't the link to the NZ mx5 club above say that the ratio for a 1.6 is 4.1? I always thought they were a 4.1.

I'm only asking because I want to change the diff on my car to lengthen the gears out a bit and I want to make sure I choose the right ratio. At the moment my '89 NA has about 125rwkw and first gear is such a non-event that I have to change gear about the same time as I press the thottle!

[Craig]

Didn't the link to the NZ mx5 club above say that the ratio for a 1.6 is 4.1? I always thought they were a 4.1

For OZ delivered cars the 89-93's were a 4.3, the 94-97's were a 4.1, the 98-2000 was a 4.1 (10AE and Heritage are 3.9 as they are limited edition 6 speeders) and the 2001 onwards were 3.636

That said other markets and especially the JDM market had all sorts of ratios, models and combo's of 5 or 6 speeders to add to the fun.

Craig

[glen73]

try this site out luke for drivetrain http://members.aol.com/solomiata/Drivetrain.html


now i have a 89 import which has a lsd. how can you identify which is what diff? as i have found out.....the jdm's are like a box of chocolates.