drifty325i 0 Report post Posted May 23, 2007 (edited) Hey im almost ready to tune the V8 with the link (will post up pics this weekend ) But i no ill have to change the ratio in the lsd to suit the torque,power and gearbox of the new motor. Now it currently has a medium case A)3.73 lsd, 225/45/16 tyres final drive ratio of 0.86 Giving me an open road of 3074rpm @110kph in 5th Now as you could imagin this does not suit a 300hp v8 in a car that weights around 1185kgs. Im thinking a diff swap to 3.23 lsd this will give me a open road of 2662rpm @110kph or C)2.93 lsd open road of 2414rpm @110kph How hard or easy is it to swap the internal ratio over? ie, keep the same diff just change the ratio and possibily the amount of lock from 25% to say 45%? What are your guys thoughts? Gus,Andrew,Yuen,Glen etc ? Cheers Riley Edited May 23, 2007 by drifty340i Quote Share this post Link to post Share on other sites
bmwsparkle 3 Report post Posted May 23, 2007 We did talk of swapping that time man, I really do need a different ratio. Flick me a text again. Quote Share this post Link to post Share on other sites
drifty325i 0 Report post Posted May 23, 2007 We did talk of swapping that time man, I really do need a different ratio. Flick me a text again. Might be the go mate, im just a little concerned its a bit to worn? and from what im told its expensive for a rebuild. Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted May 23, 2007 Give Diff Specs a ring for a price on the swap.... Ph. 2745741 Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted May 23, 2007 Ooooops....you live on a little island.....lol Thats an Auck number I gave you Quote Share this post Link to post Share on other sites
drifty325i 0 Report post Posted May 23, 2007 Haha ill give them a call for reference. cheers Quote Share this post Link to post Share on other sites
Matty 0 Report post Posted May 23, 2007 A G Bell in "Modern Engine Tuning" (p231) recommends a gearing of 24-27mph/1000rpm for a 3.8-4.2l engine with a 5 speed manual. It's a great book worth taking the advice of. That equates to a final drive of between 3.08 and 3.47. So the 3.23 should be perfect. Quote Share this post Link to post Share on other sites
bumpstop325 0 Report post Posted May 23, 2007 Im in the same place as you. Instead of 3500rpm at 110k with a 4th gear of 1:1 diff 3.46:1, so im going for a diff ratio of 2.79:1 to suit my needs better. But i can seem to find the link to the website to buy new LSD clutch packs for US$65???? Can someone repost it. Im not looking forward to how much it will cost me for the swap. Quote Share this post Link to post Share on other sites
E30-323ti 66 Report post Posted May 23, 2007 Hey im almost ready to tune the V8 with the link (will post up pics this weekend ) But i no ill have to change the ratio in the lsd to suit the torque,power and gearbox of the new motor. Now it currently has a medium case A)3.73 lsd, 225/45/16 tyres final drive ratio of 0.86 Giving me an open road of 3074rpm @110kph in 5th Now as you could imagin this does not suit a 300hp v8 in a car that weights around 1185kgs. Im thinking a diff swap to 3.23 lsd this will give me a open road of 2662rpm @110kph or C)2.93 lsd open road of 2414rpm @110kph How hard or easy is it to swap the internal ratio over? ie, keep the same diff just change the ratio and possibily the amount of lock from 25% to say 45%? What are your guys thoughts? Gus,Andrew,Yuen,Glen etc ? Cheers Riley Hey Riley, Sounds like things are comign alng well!! Are you running a W55?? When I first got mine on the road I had a 3.46 with tha W58 (0.78 5th IIRC) Was spinning ~2200rpm at 100kph, and would do 190 at the end of 3rd That was with 225/45 R16's The gearing was a bit tall, but perfectly acceptable. The 1JZ has a fatter torque curve (slightly lower peak) than the 1UZ (stock Vs stock) so the gearing isn't so important. I'm now running a 3.73 (toyota) with 245/40 R17's (about 1" taller), and the gearing is a little shorter than before. Can still use 3rd out of the hairpin at Manfield and have plenty of pull (2nd was tyre smoke central). I have also run a 3.91 (bmw & toyota) and a 4.11 (toyota), the 4.11 was way to short Chuck a few ratios in, open diffs are cheap and easy to put in, see if you like it before swappign the guts over. I have a PDF at home (NZ) with how to tear down & reassemble the BMW diffs, would be of use if you were to DIY it. I think I sent it to Andrew to put up somewhere?? Personally I'd pay someone, shouldn't take long/cost much for a diff guy to do. Let us know how you get on!! Quote Share this post Link to post Share on other sites
drifty325i 0 Report post Posted May 23, 2007 Hey Riley, Sounds like things are comign alng well!! Are you running a W55?? When I first got mine on the road I had a 3.46 with tha W58 (0.78 5th IIRC) Was spinning ~2200rpm at 100kph, and would do 190 at the end of 3rd That was with 225/45 R16's The gearing was a bit tall, but perfectly acceptable. The 1JZ has a fatter torque curve (slightly lower peak) than the 1UZ (stock Vs stock) so the gearing isn't so important. I'm now running a 3.73 (toyota) with 245/40 R17's (about 1" taller), and the gearing is a little shorter than before. Can still use 3rd out of the hairpin at Manfield and have plenty of pull (2nd was tyre smoke central). I have also run a 3.91 (bmw & toyota) and a 4.11 (toyota), the 4.11 was way to short Chuck a few ratios in, open diffs are cheap and easy to put in, see if you like it before swappign the guts over. I have a PDF at home (NZ) with how to tear down & reassemble the BMW diffs, would be of use if you were to DIY it. I think I sent it to Andrew to put up somewhere?? Personally I'd pay someone, shouldn't take long/cost much for a diff guy to do. Let us know how you get on!! Hey things are really comming along well now and im getting quite excited. Yip running a rebuilt w55 tomota gearbox, with a rear mount leaver point. And hopefully a short shift kit if i can find one??? I think the 3.23 will do the trick buy the look of your info, cheers for that. And i think ill just pay someone to do the diff right lol, save mucking around aye. Quote Share this post Link to post Share on other sites
