Yet another E30 to E36 question

[318TIRJC]

Ok so i understand the front suspension on a 96 318ti is not the same on the E30 but the rear is. Now if i wanted to upgrade my suspension so that it could help to hold the weight of a new M52 engine, would a e30 do this good? Also does the e30 suspension and springs bolt up? or what would you also have to replace in order to do this swap? For the fron i was thinking about just using the shocks from a e36 328 to help with the added weight. If anyone could help me with things i will also want to replace i would appricate the help. Thanks

[cooljess76]

No, the e30 rear suspension is not an upgrade. While the Ti's setup is similar, the e30 trailing arms and such are not better. The rear suspension isn't going to be a huge factor when doing an engine swap anyway. The rear diff should be replaced with a medium cased diff out of say a 6cyl e30, e24, e28, m coupe or Z3. Mcoupe and Z3 diffs are expensive, but bolt right up. The 6cyl e30 diffs bolt right up also, but the e24 and e28 diffs have better ratios. e24's and e28's offered a 3.25 and a 3.46 ratio, but the covers and flanges will have to be swapped with one off of an e30, m coupe or Z3. 4cyl's use small cased diffs which will self destruct from the added torque of an engine swap. As for rear suspension, you could upgrade to Z3 or M coupe stuff, but again it's not necessary. You'll benefit much more by upgrading the front suspension to an aftermarket 6cyl e36 setup ie; Bilstein sports/Koni adjustables w/H&R race or sport springs for a 6cyl e36. Instead of worrying about rear suspension upgrades, spend that effort and money upgrading your front brakes and suspension.

Also FWIW, 328 struts alone won't do anything. You'll want stiffer spring rates in the front to accomodate the extra 80 or so lbs from the 6cyl engine. If you go with aftermaket springs, you should use sport tuned struts such as Bilstein or Koni.

[318TIRJC]

Thanks for the help, thats exactly what i needed to know. Now i just need to get ordering all the parts.

[Bluebimma]

Another suggestion:

Get the battery out of the engine bay, its not meant to be there with the 6 cylinder. Any stock 6 cylinder e36 spring is good up front, rears are still fine, but if you want to get picky with it, upgrade them as.

[cooljess76]

Good suggestion Tony, I forgot to mention the battery. Idealy you'll want to displace about 40lbs from the front to the rear to maintain the vehicles natural weight balance. relocating the battery and purchasing a carbon hood should be just about right. Or you could relocate the battery and throw a full sized spare wheel/tire back there and you should be all good.

[Bluebimma]

Mine is relocate and a/c system completly removed it moves a good amount of weight that was once up there.