6 speed LSD Mk1 gearbox build

Discussion and technical advice for 84-89 AW10 & AW11 MR2. 3A-LU, 4A-GE, 4A-GZE.

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PW@Woodsport
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Re: 6 speed LSD Mk1 gearbox build

Post by PW@Woodsport »

Interestingly the new 4.312 FD ratio for the 6 speed takes the theoretical top end speed up to 144mph v 128mph on the 5 speed, assuming the 4a-ge has the power to get it there.
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gon
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Re: 6 speed LSD Mk1 gearbox build

Post by gon »

no prob, thank you Paul for all your contribution, including this thread.

I have pictures of the crown and pinion of the c52 and of the c64 (celica T sport) if anybody fancies counting teeth I can put them up.

The C64 (celica and corolla T sport) does have a 4.53 final ratio

I am attempting to put the gear ratios of the C64 inside a C52, and keeping the mk1b driveshafts, for that I am trying to swap the spider gears inside the open diff... let us see how that goes ....
PW@Woodsport
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Re: 6 speed LSD Mk1 gearbox build

Post by PW@Woodsport »

Interesting idea swapping the spiders, wouldn't it just be easier for you to run a pair of Mk2 shafts though?

That really is job done and they are stronger than Mk1 shafts.
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gon
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Re: 6 speed LSD Mk1 gearbox build

Post by gon »

It would be, but budget is reallyyyy tight now...

I will see if I can get the clearances right, if not I will have to spend another 100 quid on them shafts ... but then if I already have the shaft I would probably get the mk3 lsd .... and the missus will not be happy at all :mrgreen:
PW@Woodsport
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Re: 6 speed LSD Mk1 gearbox build

Post by PW@Woodsport »

Who is in charge of the Mk1 knowledge base these days?
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Peter Gidden
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Re: 6 speed LSD Mk1 gearbox build

Post by Peter Gidden »

PW@Woodsport wrote:Who is in charge


wassat?

:mrgreen:
The Silver Fox
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Re: 6 speed LSD Mk1 gearbox build

Post by The Silver Fox »

Paul,

I have no technical knowledge of gearboxes but given that your long fifth gear mod also has a ratio of 0.725, what are the differences in performance between the boxes? Am I correct in assuming the six speed box will give better acceleration?
jimi
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Re: 6 speed LSD Mk1 gearbox build

Post by jimi »

Excellent write up Paul :thumleft: Do you mind if I copy it it for KY2 ? Credited to you of course :)
stenky
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Re: 6 speed LSD Mk1 gearbox build

Post by stenky »

The Silver Fox wrote:Paul,

I have no technical knowledge of gearboxes but given that your long fifth gear mod also has a ratio of 0.725, what are the differences in performance between the boxes? Am I correct in assuming the six speed box will give better acceleration?
The contribution of this gearbox is twofold. Gears 2,3,4,5 provide better performance due to slightly shorter gearing. Namely its +7,7%(2nd) +13,1%(3rd) +20,3%(4th) and +12,4%(5th) torque to wheels increase over C52.
6th retains highway cruising efficiency as the fifth 0.725x4.312 mod.
Basically a win-win situation. Performance without compromising fuel consumption (not that I cared about this much).
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PW@Woodsport
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Re: 6 speed LSD Mk1 gearbox build

Post by PW@Woodsport »

jimi wrote:Excellent write up Paul :thumleft: Do you mind if I copy it it for KY2 ? Credited to you of course :)


Yes by all means Jimi fire away mate, i'm trying to get it added to the Imoc KB but not much response yet..... Imoc seems to be a ghost ship with nobody at the helm these days! :D

Thankyou for clarifying Stenky.
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jimi
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Re: 6 speed LSD Mk1 gearbox build

Post by jimi »

PW@Woodsport wrote:
jimi wrote:Excellent write up Paul :thumleft: Do you mind if I copy it it for KY2 ? Credited to you of course :)


Yes by all means Jimi fire away mate

Cheers Paul, it's done http://www.mr2oc.co.uk/know-your-2-know ... bartid=272 8)
stenky
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Re: 6 speed LSD Mk1 gearbox build

Post by stenky »

jimi wrote:
PW@Woodsport wrote:
jimi wrote:Excellent write up Paul :thumleft: Do you mind if I copy it it for KY2 ? Credited to you of course :)


Yes by all means Jimi fire away mate

Cheers Paul, it's done http://www.mr2oc.co.uk/know-your-2-know ... bartid=272 8)
yay, my gearbox is going to be famous :D
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coanda
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Re: 6 speed LSD Mk1 gearbox build

Post by coanda »

Thanks for taking the time to share this with us Paul - will come in handy in the future considering how far away I am from Woodsport.

Any problems with the 4agze?
PW@Woodsport
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Re: 6 speed LSD Mk1 gearbox build

Post by PW@Woodsport »

I've been asked that a few times, in terms of fitting the gearbox to the engine it will fit, the SC shafts won't work though, they would need to be Mk1 for non LSD or Mk2NA for LSD.

What isn't clear is wether a SC has the same gearbox mounting position, i always presumed they were the same but when i came to put a SC engine into a Mk1 NA one time i had to modify the mounts.... so i'll have to say yes it will fit but might need torque mount mods.
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MartG
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Re: 6 speed LSD Mk1 gearbox build

Post by MartG »

IIRC The rear torque mount on an SC has, in addition to the two bolts that go vertically up from below, two bolts that go horizontally through the crossmember :-k
PW@Woodsport
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Re: 6 speed LSD Mk1 gearbox build

Post by PW@Woodsport »

Thanks Mart, i knew about the extra bolts, but i also think the torque mount relative position to the gearbox is also different, i think it's because the SC box is E series based and Mk1 NA box is C series.
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PW@Woodsport
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Re: 6 speed LSD Mk1 gearbox build

Post by PW@Woodsport »

Back to my question earlier last week, who is in charge or has access to the Mk1 Knowledge base? I think this article has enough merit to be added instead of it disappearing off list into the archives.
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stenky
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Re: 6 speed LSD Mk1 gearbox build

Post by stenky »

Looks like censorship>>expanding KB
I am sooo getting punished for this, but phuket :eye:
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elbon50
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Re: 6 speed LSD Mk1 gearbox build

Post by elbon50 »

PW@Woodsport wrote:Back to my question earlier last week, who is in charge or has access to the Mk1 Knowledge base? I think this article has enough merit to be added instead of it disappearing off list into the archives.


I would suggest PMing Lauren or Chris (Limey) about that Paul
cartledge_uk
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Re: 6 speed LSD Mk1 gearbox build

Post by cartledge_uk »

You can add it yourself paul

see this thread

http://www.imoc.co.uk/forums/viewtopic.php?t=76755

Or I can for you if you want :thumleft:
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