Rear arch graft?

[cwatt]

Well, I've been planning to go CSL reps after seeing two e30s with them. Problem is, I've come to find out both those vehicles are early models with late model plastic bumper conversions. I had long-ago read that late-model plastic bumper swaps almost always end up looking like crap, which is why I recently bought a '90 as my starting platform.

I'm now having a little crisis as what to do. Do I keep going down the late-model road and start looking at how to graft in the higher early-model rear arches to clear the 18" rims, or do I abandon the project and restart with an early model and figure out how to make the late-model plastic bumper swap look at clean as the two examples I've seen *below

thoughts?

note: please don't bother responding if you're going to question or criticize my intent to go with 18" CSL wheels. this is not the time nor the place.

[MR 325]

I'm not seeing the reason to cut up or abandon the car unless you're planning to run huge tires.

What size tire do you want to run? You could simply go with a 215/35/18 or 225/35/18 and it would be roughly the same overall height as the original bottlecap/basketweave tires.

[cwatt]

I'm not seeing the reason to cut up or abandon the car unless you're planning to run huge tires.

What size tire do you want to run? You could simply go with a 215/35/18 or 225/35/18 and it would be roughly the same overall height as the original bottlecap/basketweave tires.

My primary concern is not having the wheel inside the fender (primarily for aesthetic but also functional reasons).

Re: tires, in all honesty, I don't know sizes well enough to comment. I like the 'full' wheel-well look, but I'm most concerned about ride quality. I do not like stretched tires for a many reasons.

For what it's worth, I am mentally preparing to do some inner fender modifications to avoid rubbing or loss of steering angle (if need be).

[MR 325]

If you're concerned about ride quality you really shouldn't be installing 18" wheels on an E30. Or even 17" for that matter...

[FLG]

If you're concerned about ride quality you really shouldn't be installing 18" wheels on an E30. Or even 17" for that matter...

Agreed.

Not criticizing your intent, from a completely functional stand point... 18s just are not a good idea, and 17s are pushing it.

Sent from my SCH-I545 using Tapatalk 2

[cwatt]

If you're concerned about ride quality you really shouldn't be installing 18" wheels on an E30. Or even 17" for that matter...

Agreed.

Not criticizing your intent, from a completely functional stand point... 18s just are not a good idea, and 17s are pushing it.

For what it's worth, if they made CSL reps in 17s, I would go with that.

Re: my original 'ride quality' comment, I meant that with regard to rolled tires. I've driven on them and in addition to the constant concern of damaging the lip of the rim, I thought they rode like crap. Having a sidewall feels a lot better, so that's what I meant by 'ride quality'.

*An aside*

Worth mentioning, I'm going to be upgrading the suspension front and rear, likely BC Racing w. Swift springs. They seem to offer a great bang-to-the-buck package in terms of improving ride quality while offering mild adjustability. I'm also going to be running more suspension travel and overall ride-height than most. I'm not a subscriber to the lower is better philosophy. I've gone down that path and don't find it ever works out like people suggest it does. I'm all for a low centre of gravity, but in my experience good chassis bracing and anti-roll systems are more than adequate for what most peoples' needs are, without going the Stance Nation route.

[AndrewBird]

Do you even gain anything going to an early model? I always assumed it was just the fender opening that was lower, not the inner fender as well.

[Thujalvi]

For what it's worth, if they made CSL reps in 17s, I would go with that.

http://www.apexraceparts.com/3-Series-BMW-E30_c_31.html

http://www.apexraceparts.com/3-Series-BMW-E30-M3_c_13.html

There we go, problem solved.

[cwatt]

http://www.apexraceparts.com/3-Series-BMW-E30_c_31.html

http://www.apexraceparts.com/3-Series-BMW-E30-M3_c_13.html

There we go, problem solved.

Thanks for the feedback, I honestly do appreciate it. I am however already aware of Apex and their wheels. I am not a particular fan of their CSL-style wheels nor do I want to run 8.5" in the front. There are CSL-reps avail. in 8" for the front and 8.5" for the rear. I believe this to be a great balance for an e30 with upgraded power and also provides the best fitment.

[cwatt]

Do you even gain anything going to an early model? I always assumed it was just the fender opening that was lower, not the inner fender as well.

I too believe you are correct - fender opening is the primary difference. The issue with the CSL wheels is that the offset pushes them very (very) close to the fender as it is.

The issue is that even with early model e30s, significant fender rolling is required. Since the trailing arm path under compression increases camber, as the wheel moves up and into the fender, it'll lean in offering clearance on the higher wheel arch. This works relatively well where you can run close to stock camber figures. On a late model with the lower arch, you'll be forced to run negative camber to avoid fender contact. There are photos of late-models with 18s illustrating this problem and also why many people say 18s do not look good on these vehicles.

[nando]

Honestly I think fears of running wide/large tires inside late fenders is pretty overblown. if a 235 r-comp will fit rolling the rear fenders, I see no reason why a 225 street tire wouldn't.

I think the problem is most wheels are just too low offset to fit a real tire, or people add spacers/adapters which makes the problem worse.

rolling the fenders shouldn't stop you, every E30 should have rolled fenders.

[ForcedFirebird]

They're semi-rolled from the factory, just finish them up.