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  #11  
Old 14-01-2020, 05:42 PM
SammyZ3M SammyZ3M is offline
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Fast road. Occasional tracj, I feel the stock diff is too long. I have driven an e46 m3 with a 4.1 and felt good so thought I’d comprised and go 3.9. Maybe 3.7 if one comes forsale
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  #12  
Old 14-01-2020, 10:49 PM
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c_w c_w is offline
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Cant compare e46 directly as they run bigger wheels, so although the actual gearbox ratios are similar, with an same ratio diff the e46 would be relatively longer geared. 3.64 or the 3.73(?) would be good on track to use 3rd/4th/5th.

I put a 3rd clutch in mine for a while which is supposed to give 40% lock over stock 25%, but in all honesty it didn't need it and also i think it introduce understeer on turn in. With decent semi slicks the car doesn't need any mods to the diff from my experience. The balance of modest torque and r888s meant it could be driven flat out in dry out of corners.

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Originally Posted by fok View Post
I’ve just read c-w’s reply and I would add that I ran an E30 LSD in 3:46 with nearly 400rwhp for 10000 miles with no problems when my car was LS1 powered.

I’m back to the OEM 3:15 now with the bigger power LS3......we’ll see how it goes.
Yea I was thinking with a v8 it would need stock or longer, but depends on the gearbox ratios.

Last edited by c_w; 14-01-2020 at 10:55 PM.
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  #13  
Old 15-01-2020, 09:58 AM
SammyZ3M SammyZ3M is offline
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Cheers for the reply, yeah might go for the 3.73 and I’m using 18s same as th e46 I’ve driven
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  #14  
Old 15-01-2020, 11:48 PM
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Is it same size tyre though? Stock z3m rear wheel is 245/40/17 but e46 m3 18” is 255/40/18, significantly bigger overall.
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  #15  
Old 16-01-2020, 08:48 AM
SammyZ3M SammyZ3M is offline
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235/35/18 which is what I’ll be running on the z3m anyway
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  #16  
Old 16-01-2020, 10:21 AM
maph maph is offline
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Quote:
Originally Posted by c_w View Post
Is it same size tyre though? Stock z3m rear wheel is 245/40/17 but e46 m3 18” is 255/40/18, significantly bigger overall.
Correct.....

245/40/17 diameter is 24.7
235/35/18 diameter is 24.5
255/40/18 diameter is 26
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  #17  
Old 16-01-2020, 10:59 PM
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Best ratios are
3.46 for 5 speed
3.64 for 6 speed
3.9 would be painful. No 1st gear to speak of and in top at 80 it would be screaming it’s Tits off
On a run you would be deaf , and skint
My 3.64. Was hard work on a long run with the 5 speed
Awesome through the gears though
Now with 6 speed best of both worlds
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  #18  
Old Today, 11:10 AM
SammyZ3M SammyZ3M is offline
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Cheers I’ll keep that in mind
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