mk4 rear end in a mk3?

JZa80

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Mar 6, 2009
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has it been done and what would it all require wouldnt it jsut require a custom drive shaft custom flanges for the axles also? if thats all has anyone done this and what gear ratios did they all come with
 

shaeff

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If you're going through that trouble, go with a Ford 9" setup like IJ.'s

Not to mention that the MKIV rear isn't a good match for the MKIII's transmission ratios.
 

JZa80

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ok. i was jsut wondering i dont have a welder and wont have one till like this winter. im jsut going to wait it out and buy a nice one right off the bat. but i was hoping that would be a nice little upgrade. ill look into what IJ did and see what i can come up with.
 

JZa80

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also how hard will it be to daily drive that car with a ford 9 inch will it make a noticable difference in handling? because this is going to be like a summer car. take it to cruises. to the track. and go to small events that my uncle and aunte hold at their dealership maybe stick it sideways every once in a while. would the ford 9inch still be the best idea?
 

figgie

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what?

depends on the gearing......

to tall, sucks at the street. To short. Sucks at highway.

For the work, both will require about the same. Ford 9" will have a vast array of different gearing. MKIV rear end. Not so much choices.
 

JZa80

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ya what owudl be ebst for like in the middle. i want decent highway driving becasue this car will make some trips and the street it will have a little fun like i said might slide it around a little go to the track jsut a overall street/strip car. but im choosing between 3.73,3.90,4.10 any ideas? and would mig welding be strong enough for the welding or mine as well go tig?
 

JZa80

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thanks ya tit still all ahs the stock undercoating on it. but i can say the underbody is minty as ever. im jsut going through debating to do ford 9 inch or beef eveythign up on the stock and jsutg et custom axle shafts and everythign amde. becase this car will be up for sale in the future. to get a nice start towards a mk4 payment. but im loiking the ford 9inch idea but have to look more into it. any threads or write ups on it? i cant find it in ij's what i did today thread haha its only 392 pages
 

toy fanatic78

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Why change the MK3 rear end for an occasionally beat daily driver?
The stock LSD rear end is rather durable,and can handle quite a beating at moderate power levels.
And there are a few choices of gear ratios(I believe 3.54:1 is the lowest you can get in that housing)IIRC the factory offered 4.30,4.10,3.90's,maybe a couple more.
 

SupraClaou

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Sep 1, 2006
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Factory rears for mk3 A70 Supra from lowest to highest:
3.727, 3.909, 4.100, 4.300,
And there is a Turbo A spec rear end of 3.2 which is very very rare! :aigo:
We can go lower until 3.5 which is the limit on our rear 'case'....:naughty:
Jawsgear custom made this 3.5 gear and pinion...

The mk4 rear diff is only good for the V160/V161 Getrag 6 speed manual trans. Otherwise there is no need going that route.:nono:
The twin-turbos mk4 supras that came with the 6 speed getrag... had either a 3.1 or a 3.2 rear (jdm spec only).
So with the 5 speed R154 trans of the mk3 and the mk4 rear (3.1 or 3.2 rear) is useless. Some people even
say that the 3.7 rear is quite tall....figure out. Though I love tall gearing,and the 3.7 is ok with me!

The mk3 rear is an 8 inch diff
The mk4 rear is an 8.5 inch diff for the first years (93.5 - 95 models)...
after 1995 the mk4 had a 8 inch rear diff like the mk3 :biglaugh:
Stock mk3 trans & rear diff can hold up to 600 rwhp with all kinds of abuse
and driving style.And up to 800 rwhp being gentle with 'it' and not doing
1/4 miles on the dragstrip :sarcasm:
 
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IJ.

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shaeff;1295003 said:
If you're going through that trouble, go with a Ford 9" setup like IJ.'s

Not to mention that the MKIV rear isn't a good match for the MKIII's transmission ratios.

NOOOOOOOOOOOOOooooooooooooooooooooooooooo............................. ;)

Damn expensive option as EVERYTHING was custom if I had to do it again I'd find an existing Big IRS pumpkin and adapt it to work.
 

shaeff

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LOL, well, I lust over your rear, Ian. Lust. Your rear. Me.
 

jimi87-t

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Oct 12, 2005
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Haha thats just nasty...

But yeah, why change out the rear-end? If it is in question, have it rebuilt, they are not weak.

Or maybe you are nuts and have a ton of money like Ian....:icon_razz
 
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JZa80

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becasue i was aprting eht car for a buddy we sold the 3.90 LSD and i had a spare 4.10 open form a na surpa and put it in so somsone coudl sitll get the shell no one was budging on it so im going to od a mini project and dont feel like waiting and struggling to find a 3.90 lsd because i can never seem to find anyone selling them
 

SupraClaou

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Sep 1, 2006
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SupraOfDoom;1295155 said:
Turbo A 3.2? Really?

Yeah.....
p1295573_1.jpg

p1295573_2.jpg

p1295573_3.jpg


Very rare....so rare that many people don't believe that this thing really
exist! One guy here in Europe has one piece :naughty::biglaugh: