Originally posted by xLibelle
View Post
Let's think also the following data about E30 dan E28 front struts.
1) The guide support on E30 and E28 front struts are similar, BMW part number 31331139452
2) The upper spring plate on E30 and E28 front struts are also similar, BMW part number 31331128524
3) Ditto for upper spring pad, BMW part number 31331128523
4) And the lower spring pad too, BMW part number 31331124322
Meaning that E30 front springs can be used on E28 front axle.
This conclusion is confirmed by the discussion in Stancework forum (www.stanceworks.com --> tech --> ride control --> E28 lowering with E30 parts).
See also the discussion in MyE28 forum (www.mye28.com --> Tch Talk --> Spring diameter E28 vs E30)
Next, we need to shortened E28 front strut in order to install the E30 strut insert in E28 front strut housing.
After googling, I found out the following dimension:
E28 P36-0243 BMW E28 Sport insert tube 432 mm length
E30 P36-0335 BMW E30 325i Sport insert tube 418 mm length
Both having P36 = 36mm piston diameter
Thus, the E28 front strut housing need to be shortened 14mm (432mm - 418mm).
Checking the caster angle on both E28 and E30, I found out that:
E28 front caster angle +8 deg 46' + 30'
E30 front caster angle +8 deg 30'
We can use E36 M3 eccentric front control arm bushing to adjust the difference
Those are my investigation so far by comparing the available information from the internet.
Other advantage of using E28 front strut to make 5 lug conversion to E30 is the possibility to use larger front disc brake (280mm E28 front disc diameter compare to 260mm of E30 front disc diameter).
Cheers,
pungky29 - BMW Car Club Indonesia
Comment