EOI: Custom Gemini diff conversion R&D and manufacture

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Fazio
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Post by Fazio »

so with this just being a center, whats the estimated price and what would need to be supplied?
got my te gemi for $220 :)
new coupe... project under construction
http://www.ozgemini.com/forums/non-tech ... ight=fazio
Turbocoupe75
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Post by Turbocoupe75 »

Hey all sorry to join the conversation late, I have been looking through all the posts regarding up grading the gemini diff to a stronger item,

I'm curious to know why a cut down VL 5.0 LSD disc brake item is so unpopular??????

I have one am looking into cutting one down for my coupe and switching to a four link rear.
The crummydore diff is strong, common and "cheapish" and there are a few different ratios to suit. There are of course engineering issues, and the cost of cutting down axles and welding on mounts ect ect. But surely this could be all done for under $1000 in including the diff??? with a little bit of home engineering (excluding professional engineering)
eg:
-My diff cost (free) $$maket value $400?
-axles cut and re-splined $200
-weld up gemini suspension mounting points (free)
-fabricate 4 link pick up points (engineering input recomended)
#Turbocoupe75
Gene FJ20DEBT
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Post by Gene FJ20DEBT »

But surely this could be all done for under $1000 in including the diff???
lol!!!

diff - what ever u paid.. say $400
shorten housing and weld gemini brakets on.. $750
shorten and respline axels $300
tail shaft - $350
4 link kit $800+ or ladar bar kit $500
then u have all the mods tot he car to fit the 4link which would be a heap.. a little work in the ladar bar....

then u need to buy a LSD and ratio that u want...

no way u would do it for a grand
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Turbocoupe75
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Post by Turbocoupe75 »

LOL back, I reckon i could do for close to $1000, I'm not saying it would be easy, there is no reason that allot of the fabrication couldn't be done in the back shed with a little planning and design

diff - what ever u paid.. say $400
-I got my LSD diff for free with disc brakes


shorten housing and weld gemini brakets on.. $750
Free, I have a welder and access to a drop saw


shorten and respline axels $300$200 or free if I do it myself It helps a mate has a mill and dividing head, not sure how much it is to get them heat treated?

tail shaft - $350 why pay someone??, measure cut weld I can do that myself, pay to get it balanced though

4 link kit $800+ or ladar bar kit $500
then u have all the mods tot he car to fit the 4link which would be a heap.. a little work in the ladar bar....
No way im paying $800 for a kit, cut the pickup points and upper links from another car and fabricate suitable mounting points on the underside of the gem.


won't hurt to give it a go!
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Gene FJ20DEBT
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Post by Gene FJ20DEBT »

Turbocoupe75 wrote:LOL back, I reckon i could do for close to $1000, I'm not saying it would be easy, there is no reason that allot of the fabrication couldn't be done in the back shed with a little planning and design

no eveyone have ability to do so in there back shed

diff - what ever u paid.. say $400
-I got my LSD diff for free with disc brakes


not everyone is goning to get a diff for free

shorten housing and weld gemini brakets on.. $750
Free, I have a welder and access to a drop saw


dodgy... got a jig to make it straight?

shorten and respline axels $300$200 or free if I do it myself It helps a mate has a mill and dividing head, not sure how much it is to get them heat treated?

not everyone has mates with machinery liek that

tail shaft - $350 why pay someone??, measure cut weld I can do that myself, pay to get it balanced though

cos not eveyone has welding abilitys to do so.. and somehtign like a tail shaft i would be paying a pro to weld up, even if i could weld

4 link kit $800+ or ladar bar kit $500
then u have all the mods tot he car to fit the 4link which would be a heap.. a little work in the ladar bar....
No way im paying $800 for a kit, cut the pickup points and upper links from another car and fabricate suitable mounting points on the underside of the gem.


again, dodgy.. cut and shut suspension parts.. awsum....

won't hurt to give it a go!
might hurt when the tailshaft comes apart and tears through the floor

you said
I'm curious to know why a cut down VL 5.0 LSD disc brake item is so unpopular??????
maybe for you its cost effective cos u know peoepl who can do this and that, and u have welding skills etc.. your question was a general "why dont peoelp like shortened commodore diffs cos they can be done under a grand" and my answer was a general reply to that..

cant say i would like to have a housing cut and welded up in the back yard with out the use of a jig to make sure its straight...
either way. i doubt u will do it under 1000$... not to mention have it legal. for under 1000$

------
anyways, this isnt the thread to be asking about comodor diff conversions.
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Turbocoupe75
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Post by Turbocoupe75 »

No worries, so cost is the reason it's is so unpopular

I was more worried about weight or physical size of the diff or difficulty of obtaining a suitable diff ratio, rather than the cost or difficulty of installing a vl diff.
I'm curious to know why a cut down VL 5.0 LSD disc brake item is so unpopular??????
apologies wrong forum...nuff said, ill just go do it n post some pics!
#Turbocoupe75
F3ARED
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Post by F3ARED »

VL diffs are the same as VN-VS live axle ones. LSD centers are easy to find as are different gear ratios. This was the path i was going to go down - cost is 1800 through McDonalds bro's racing including shortening, fitting and all however...

Some engineers like it, some dont. IF this idea materializes then its alot easier to get it passed off seeing as it bolts in.
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macca_loto
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Post by macca_loto »

Turbocoupe75 wrote:Hey all sorry to join the conversation late, I have been looking through all the posts regarding up grading the gemini diff to a stronger item,

I'm curious to know why a cut down VL 5.0 LSD disc brake item is so unpopular??????

I have one am looking into cutting one down for my coupe and switching to a four link rear.
The crummydore diff is strong, common and "cheapish" and there are a few different ratios to suit. There are of course engineering issues, and the cost of cutting down axles and welding on mounts ect ect. But surely this could be all done for under $1000 in including the diff??? with a little bit of home engineering (excluding professional engineering)
eg:
-My diff cost (free) $$maket value $400?
-axles cut and re-splined $200
-weld up gemini suspension mounting points (free)
-fabricate 4 link pick up points (engineering input recomended)
I work in this industry of chassis work and diff work etc.

You can respline and axle but what heat treating is on the axle to begin with? If it has been case hardened it will need re heat treating...

Your mate may have a mill but does he have a broach to cut the splines? Not a cheap machining tool at that either.

Yes you can cut your diff tubes but i guarantee not in a million years will the cut of a drop saw be accurate enough to just "slap" the ends onto and weld up.

The reason we have engineers in this country to sign stuff of is for people like you who think they can wing it.

Using suspension parts off another car isnt going to work either. Not unless they work in the exact same configuration they came off in. But hey if you dont want to pay $800 for a universal 4 bar kit then off you go. I can tell you know that a polished stainless 4 bar kit with brackets costs $700 COSTS $700 and takes 4 hours to put together. Make 2 a day and it doesnt even cover overheads.

The tailshaft dont even get me started on this....
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Gene FJ20DEBT
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Post by Gene FJ20DEBT »

Turbocoupe75 wrote:No worries, so cost is the reason it's is so unpopular

I was more worried about weight or physical size of the diff or difficulty of obtaining a suitable diff ratio, rather than the cost or difficulty of installing a vl diff.
I'm curious to know why a cut down VL 5.0 LSD disc brake item is so unpopular??????
apologies wrong forum...nuff said, ill just go do it n post some pics!

sorry cuz, but i need to reply.

not really the cost.. a conversion will cost u about 2000-3000, which is what peoepl are gonna pay for this thing cuz is having made up (includign stonger tube and axels, disk conversion etc... its more the legality sides of things... most engineers dont want a bar of diff conversions in geminis.. Re: one of my earlyer posts in this thread abou tthe "grey area" :lol:
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Cuz
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Post by Cuz »

Ok, now that this thread is nice and gummed up with crap, can we please move the posts not relevant to another thread?

The only legit question i saw while browsing through these posts was about pricing - please refer to the bottom of the very first post in this thread. I ouline what I have paid for the various parts of the driveline and an approx of what the LSD centre will cost to be made up.
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BAD 44u
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Post by BAD 44u »

cuz a few questions

1 will there be an option of different ratios? or only the gemi 3.9

2 will you be able install the centre yourself/ will the housing need modifing?

3 will the first be approx $3000 as a test and cheaper after that or a set price.?
Gene FJ20DEBT
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Post by Gene FJ20DEBT »

all that has been answered allready
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BAD 44u
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Post by BAD 44u »

sorry just read page 4 which i missed previously and answers my questions.
id personally be more interested in a different gear set to suit the standard diff or romac full spool than a lsd with 3.9 ratio.
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Post by Gemi Coupe »

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Last edited by Gemi Coupe on Tue Oct 26, 2010 3:28 pm, edited 1 time in total.
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Cuz
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Post by Cuz »

Just spoke to bosnjak again. They have a Petrol hemisphere and say there is no reason why what we were planning to do for the Diesel diff cannot be done for the Petrol.

They are looking at gear from Cusco and KAAZ to see what they can use as a basis for the LSD.
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