Coilovers or Shortened Springs & Shocks?

[joeseinfeld]

Sorry for the noob question, i've researched but don't feel as if i know 100% what i should do or why i should do it.

Basically, I have an E30 which i want to drop for street use (not a track car), so doesn't need "performance" suspension... simply for looks.

Should i go coil-overs (in the thousands $$), or should i just get shorter-stiffer springs and shocks (around $400)?

Is there some other reason other than performance and adjust-ability that people choose coil-overs OVER lowered springs & shocks?

I've lowered cars before.... but not European cars. In the other cars i've simply gone shortened springs and shocks all round. It seems everyone wants to put in coil-overs even though their car is only for daily use?

Cheers!

[jcbe34]

It depends on how low you want to go.. Coilovers will definitely let you lower the car a lot more while still maintaining enough travel to still be tolerable. The big thing with e30's is the need to shorten the strut housings to maintain travel while lowering the car

[joeseinfeld]

It depends on how low you want to go.. Coilovers will definitely let you lower the car a lot more while still maintaining enough travel to still be tolerable. The big thing with e30's is the need to shorten the strut housings to maintain travel while lowering the car

Yer the whole shortening the tower is still a little confusing to me... is it because the new shocks will be too short and therefore not stick out of the top of the tower far enough?

The main reason i didn't want to go coilovers was i kept reading things had to be welded etc... which i don't have the tools to do, other reason obviously cost.

What i gather from your info is that it mainly allows you to go lower, and also go lower with better travel...

Thanks for that

[joeseinfeld]

Woops, left out that i found some coilovers for E30's which don't require strut tower modification (just waiting to find out if that means it won't actually lower it a whole lot) and for about $1150... that was another thing i had to factor into making up my mind whether going shortened springs/shacks or coilovers

[Ant]

you're in luck, i have some time to kill at work...

Up front, E30s have a complete front assembly in one unit. Therefore the brake, hub etc all mount to the bottom spindle as one unit. The shock insert goes inside the shock housing and a spring on the outside. This is why coilovers are not 'bolt in'. In the rear, E30s use separate spring and shock absorber. There are kits to convert to 'true' coil over spring in the rear, but this is complex and (to be done 'properly') needs chassis strengthening.

When people say 'coilovers' it is sometimes confusing in terms of E30s. There are coilover sleeve kits / conversion kits. These are simply threaded adjustable sleeves and shorter harder springs that slide onto your front housing. Often you are required to cut the original spring perch off. This allows you to adjust height and go low however the shock inside the housing still has a range of motion. If you lower too much, the shock is already compressed with the car on the ground. This is obviously bad and this is the reason why there is a limit to how low you can go with these types of coilover kits. However, if you dont want to to THAT low and carefully match the springs and shocks you can sometimes get away with it. Some people have moderate success with cheap JOM stuff. This comes with replacement shock inserts, springs and adjusters. Rear has replacement shocks, springs and adjusters.

To avoid the travel issue and to very low, what people do is buy inserts that are Shorter and drop them inside their front housings. To do this you need to cut and shorten your housings to suit (you can fill the gap inside with a spacer, but this cancels out the whole point of a shorter insert). This shorter insert has movement at the lower ride height given by the springs. This is complicated to do though and takes some knowledge to shorten correctly. Often you may also need to weld your bottom spring perch lower on the body to suit (the adjusters then sit on top of this to wind up).

In terms of coilovers that people get for E30s, most of them come with a front coilover body which is a spring and shock in one that you need to weld to your spindle. So you remove your stock housing, cut it off about 2" above the bottom of the strut tube, slide the coilover over it, and weld it on. This new coilover body is fully threaded, so you can adjust and physically shorten or lengthen the entire housing to lower or riase the car. The springs are also adjustable. In the rear, the separate shock is threaded to shorten and length, and the springs come with adjusters as well.

The above setup is what BC, Megan, etc offer. Alternatively, there are companies like Ground Control or KW that sell off the shelf bolt in coilovers. They have already done the job of cutting and wleding a spindle on for you up front. Welding this is not dangerous if done correctly.

Therefore your options are:

- lowered springs and some shocks like bilsteins. static drop, it is what it is. cant be too low cause it would ride badly.
- coilover sleeve kit, just slip on threaded sleeves and springs. has a travel limit and may bottom out
- coilover conversion kit such as JOM. has new shock inserts, springs and sleeves. has a trave limit and may bottom out
- design you own coilover kit by cutting your housing, selecting shorter inserts and choosing your own springs. takes knowledge.
- weld on coilovers like BC etc. Need to find a trustworthy shop to do it but otherwise all good.
- buy coilovers ready to bolt in like KW or GC. these can be expensive

[joeseinfeld]

you're in luck, i have some time to kill at work...

I've probably read your post about 6 times now and i'll probably read it another 6 more.

Most helpful response I've ever read on a forum! Feel like i remotely actually understand what's going on now

I feel like you would be the man to ask then... how low (i.e. inches between centre of the wheel and top of wheel arch) in your opinion would i be able to go from factory with this type of setup without my car shaking itself to bits?


- lowered springs and some shocks like bilsteins. static drop, it is what it is. cant be too low cause it would ride badly.

Thanks again for that info... feel so much better actually knowing the differences and how it all works

[2-lo]

These links will help you.

http://www.e30owners.com/forums/showthread.php?t=7838

http://www.e30tech.com/forum/showthread.php?t=91779

[joeseinfeld]

These links will help you.

http://www.e30owners.com/forums/showthread.php?t=7838

http://www.e30tech.com/forum/showthread.php?t=91779

i came across that second link, that first one is awesome thanks!

Don't know how keen i am to use my project to learn on in terms of welding

[Adam.]

For make slammed - Coilovers
For make lowerings - springs
The most you can go on the front of an e30 on springs is 60mm, which isn't much and probably wont get rid of all the nasty wheel gap. With coilovers you can get as low as you want and have the option to raise it up.

[joeseinfeld]

For make slammed - Coilovers
For make lowerings - springs
The most you can go on the front of an e30 on springs is 60mm, which isn't much and probably wont get rid of all the nasty wheel gap. With coilovers you can get as low as you want and have the option to raise it up.

Yer by the looks of things i won't be able to go low enough without a coil over type kit like Ant mentioned...

At the moment my car looks like this with 14R/60 tyres:
Front wheel gap from centre of wheel to the top of wheel arch = 38.5cm (15.5”)
Rear wheel gap from centre of wheel to the top of wheel arch = 36cm (14”)

Can almost get my head in there lol

[Adam.]

Propper coilovers it is then