Gus 5 Report post Posted February 18, 2008 I just picked up one of these to use as a CR box on the turbo, any general feedback on these in terms of strength? as for fitting, it has the larger driveshaft rubber guibo, is this the same size as the e36 m3? i imagine i will need to get an e36 driveshaft and have it lengthed/shortened and then balanced? any ideas on cost/places to do this? also there is a sticker on it mentioning ATF..do they not use normal gearbox fluid and use ATF instead?? Cheers Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted February 18, 2008 Use ATF G3 full synthetic in that gearbox Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted February 18, 2008 Cheers Glenn..do you know where I can find the part number that matches up to the BMW etk on it? there are loads all over the place Quote Share this post Link to post Share on other sites
westy 614 Report post Posted February 19, 2008 None of the part numbers on the gbox I have match anything I could find. Its a ZF S5D320Z for 328/M3 M50 box might be ZF S5D310Z? Same ratios as far as I know. Apparently strong as all buggery! I use Redline MTL If its of any use. Quote Share this post Link to post Share on other sites
CamB 48 Report post Posted February 19, 2008 None of the part numbers on the gbox I have match anything I could find. Its a ZF S5D320Z for 328/M3 M50 box might be ZF S5D310Z? Same ratios as far as I know. Apparently strong as all buggery! I use Redline MTL If its of any use. The 5 speeds aren't really "close ratio" - they're just direct 1:1 top gear - the spacing is about the same as a normal overdrive box... but you need a longer diff. Strong is good though. Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted February 19, 2008 The 5 speeds aren't really "close ratio" - they're just direct 1:1 top gear - the spacing is about the same as a normal overdrive box... but you need a longer diff. Strong is good though. how can they be spaced the same if 5th is the same as 4th on an overdriven box? maybe its not a super close ratio box but its closer than the OD e30 box and thats enough for me glad to hear its strong! i am pretty sure its an m50 box but would not mind making sure! Quote Share this post Link to post Share on other sites
E30-323ti 66 Report post Posted February 19, 2008 how can they be spaced the same if 5th is the same as 4th on an overdriven box? maybe its not a super close ratio box but its closer than the OD e30 box and thats enough for me glad to hear its strong! i am pretty sure its an m50 box but would not mind making sure! The spacing of the gears relative to each other. say 0.2,0.4,0.6,0.8,1 is "normal" giving 0.2 betweens gears then 0.35,0.55,0.7,0.85,1 is "close" giving reducing differences between the ratios. Thus when the car is at speed there is less rpm drop between the higher ratios yet the same top speed can be achieved. The lower gears are longer as the engine has plenty of torque (when multiplied by the ratio) to drive in those taller gears, and who uses first when "racing" anyway. Thats very broad brush, but the general jist of it. As mentioned earlier the 1:1 5th boxes use a lower final drive (diff) ratio. Running the 1:1 ZF with a 3.73 diff will yeild similar results to using a 4.45 diff with a Getrag 260. Quote Share this post Link to post Share on other sites
CamB 48 Report post Posted February 19, 2008 (edited) how can they be spaced the same if 5th is the same as 4th on an overdriven box? maybe its not a super close ratio box but its closer than the OD e30 box and thats enough for me Coz if you choose a diff that offers the same rpm in 5th (eg a 2.93 for a 1:1 top or (close enough) 3.73:1 for a 0.81:1 OD box), then the ratios are **kinda** similar (I plugged it into a spreadsheet and the graphs were similar). So it's better, but not good like the real c/r Getrag - you're not really much better off than a Getrag and a ridiculously short diff. It's really about whether 1st is any use. (edit - what ^^^^ said) Edited February 19, 2008 by CamB Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted February 19, 2008 The dogleg i was using before was with a 3.23 diff..will prob go that or maybe a 3.46. using the current 3.64 will be the same as driving round in 4th with the 260. so really about your comments ^^ it depends on how short 1st is? the e36's I have driven seem much better geared than the e30... ah well, I can wait and see! even if its not as close as I hoped I am not fussed...it fits better (Ie not cut and welded), has a stronger driveshaft guibo, has done 70k, cost f**k all and I can use it for an m52 swap! Quote Share this post Link to post Share on other sites
Gus 5 Report post Posted February 19, 2008 because I am slacking off at work...i made this up....just a cobbled together thing comparing gearbox ratios Model 1 2 3 4 5 reverse E46 4.21 2.49 1.66 1.24 1 3.85 E30 325i 3.83 2.2 1.4 1 0.81 3.46 320iS 3.72 2.4 1.77 1.26 1 Spacings 1 to 2 2 to 3 3 to 4 4 to 5 E46 1.72 0.83 0.42 0.24 E30 1.63 0.8 0.4 0.19 320iS 1.32 0.63 0.51 0.26 320iS box is same as M3 so a good indication of a CR. all gears fairly similar excluding 1st...not too bad! again, that is an e46 box..i am assuming its similar Quote Share this post Link to post Share on other sites
CamB 48 Report post Posted February 19, 2008 Don't get me wrong - I reckon it's a good idea and I'd do the same. And if you multiply the gears by the FD you'll get the effective difference and you can see the ZF is sort of in between Quote Share this post Link to post Share on other sites
hybrid 1043 Report post Posted February 19, 2008 all in all gus as I said in my PM, its a better choice than the current getrag in it now. If you get the ZF m3 one .. (yours is either that or the m50 version) they are as strong as you can get in the BMW range that will bolt straight into to an e30. the zf 6speed will not fit as it is to big for the trans tunnel. drive shaft wise you will have to go the 328i e36 manual or get it fabbed up for about $500 NZ .. out of the stock one and an e36 one ... easy enough to do (what we are doing) e36 / mcoupe diffs are the same pattern wise as e30 ones. nice score I wouldnt worry too much about being down on ratio as the turbo has the power (and potential power) to compensate and infact you wont want a too short a ratio for it. Quote Share this post Link to post Share on other sites
westy 614 Report post Posted February 19, 2008 ZF S5D 320 Z ratios: 4.20 2.49 1.66 1.24 1.00 r3.89 Practicaly identical to e46. And yeah 3.64 diff is the same in fifth as std forth. Quote Share this post Link to post Share on other sites
