M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Suspension => Topic started by: achtungE30 on July 16, 2007, 11:54:53 AM
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I'm currently running H&R race/bilsteins on my car - see pic below...
(http://www.fahrfrumlosin.com/pics/Cars/BMW/070307/_MG_0151.jpg)
Is there a way to kill the fender gap in the front?
As a last resort, i'm considering GC coilovers seen here...
http://www.ground-control-store.com/products/description.php/II=121/CA=98
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I have the same problem, but it saved me $50 from having my front fenders rolled to
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What do you guys think about cutting off dead coils?
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Are you running 14's? If so, the cheapest route (and probably the better option) would be to get bigger rims. As you already know, even with the 14's the fender gap is pretty low (at least on mine it's only a little more than an inch).
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I am running 15x8 0et with 205/55-15
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im running 16x9s 205/40/16 and the stock 14 basketweaves on 195/65/14 (yea def less fender gap with 65 profile tires!)
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What do you guys think about cutting off dead coils?
Um, you better not. They were designed this way so it's best you leave them alone.
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People have cut coils for years. When I was young (late 60's) it was the only way to get a lower, stiffer spring.
When you cut coils you also change the spring rate. The amount depends on the original length and how much is cut off. A coil spring is like a wound torsion bar. The shorter the length the stiffer.
Because these are H&R Race they should be very easy to sell. Not so if a coil was cut.
I think the problem is tire size as noted above. The height of your 204/40's is 22.5". The 195/65's are 23.9". The OEM tires and wheels were 24" tall.
205/50/16's are almost exactly 24" tall. You could also remove the rubber spacers. There might be recessed upper seats for the E30.
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Bekkers Drop hats.
http://www.bekkers.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=SUFT008&Category_Code=blssuspension
They do work but need a little trimming to fit on an E30. Nothing major but I've heard they lower about a 1/2 inch not the 1.5 they advertise. With removal of your stock spring pads and these hats that gap will close up.
Hunter
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I have the same "problem" -- H&R & Bilstein Sports and not quite enough front end drop. I think perhaps the internal gas pressure of the Bilsteins doesn't allow the springs to collapse quite as much as H&R predicts. I've run H&R Sports with Koni's and the front end is 1/2-inch lower. I'm half tempted to sell my near-new Bilsteins and switch to Koni's. Anyone interested? ;)
Gary
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Although it may look good, NJ + 205-40-16 + H&R race lowered more = broken oil pan.
If you do this, I wanna start a pool going on the broken oil pan. :D
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theres ways around busting your oil pan. i know when i get that low im grabbin a skidplate. im goin h&r race on koni adjustables (at least until i can afford ground controls). ill also be looking into those shorter spring hats..
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Why would you want to do this? The car will handle worse, will bottom out regularly, may damage the dampers (stroke length will be too long). Your profile is wrong too, you should have about a 50 profile on 205 section 16" rims and I think the tyres are too narrow for the rims.
Personally, I'd spend money on getting a 225/45/16 tyre of the best possible quality.
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Why would you want to do this? The car will handle worse, will bottom out regularly, may damage the dampers (stroke length will be too long). Your profile is wrong too, you should have about a 50 profile on 205 section 16" rims and I think the tyres are too narrow for the rims.
Personally, I'd spend money on getting a 225/45/16 tyre of the best possible quality.
It's called style and bling points for some of these guys. All they want is the looks and that Euro stretch. I'm guessing the op is probably under 30yo if my guess is right. It seems the rage to have a certain Euro-stretch coupled with a low stance for a lot of the younger cats on these boards.;)
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You're so right ! I suppose most of the younger fellows were just a bling in their dad's eye when these cars were new. I have been lucky to own two E30's when they were new cars. So, it's easy to figure out i am almost a teenager...
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It's called style and bling points for some of these guys. All they want is the looks and that Euro stretch. I'm guessing the op is probably under 30yo if my guess is right. It seems the rage to have a certain Euro-stretch coupled with a low stance for a lot of the younger cats on these boards.;)
Wow, are you generalizing me? Please don't do that.:rolleyes:
So by your implication age > 30 = taste? sheesh. I'll have to remember that when a new member comes on here and I have the information he needs.
Yes, i'm 27. Yes I do enjoy the euro stretched look and I was just toying with the idea about getting the front gap reduced or eliminated. I have always admired the e30 at the tender ages of 8-14 and convinced my father to finally get a 3-series coupe in 1992, although unfortunately it was by then the e36. I learned to drive in this e36 and have been a BMW fanatic since my eyes first saw the e24 6-series in the mid 80s.
Like I stated, it was just an idea. Sorry!
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I'm over 50 and I like the lowered look myself. My car is probably lower than actungs. I think there is a fantastic mix of ages and cultures on this board, and we certainly don't want to put anyone down for having tastes different from our own. I do think your tires are what gives the tall look to your car, they look kinda short. Just my 2 cents.
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Wow, are you generalizing me? Please don't do that.:rolleyes:
So by your implication age > 30 = taste? sheesh. I'll have to remember that when a new member comes on here and I have the information he needs.
Yes, i'm 27. Yes I do enjoy the euro stretched look and I was just toying with the idea about getting the front gap reduced or eliminated. I have always admired the e30 at the tender ages of 8-14 and convinced my father to finally get a 3-series coupe in 1992, although unfortunately it was by then the e36. I learned to drive in this e36 and have been a BMW fanatic since my eyes first saw the e24 6-series in the mid 80s.
Like I stated, it was just an idea. Sorry!
Chill Bro, I think you are reading way into it. I never said anything about taste. I never stated whether that looked good or not. I never insulted you in any way. I was merely trying to explain it to people that don't understand the reasoning or the look.
I was just stating a general trend which you do fit into since you are under 30 and do like the Eurostretch look. Those are the facts. There are no opinions stated. Just the facts.
I personally do like the Eurostretch look on some cars including yours. I just personally wouldn't do it since I'm a performance junky and would rather gain a bit more slip angle on more meat.
I like it when people do their own thing as that is what car customizing is all about regardless if other people like it or not. Do not let me nor anyone else get your panties in a bunch over such a subjective topic.;)
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Just drop it with shorter springs or put higher tyrer on it.
For the same reason as you I have switched to bigger tyres.
Than the gap is not so big, and your oilpan gets a little more groundclearance.
I also added the drop hats. The brand is Bonrath, but I think it's the same.
They lower an extra cm (1/2") and now I can life with it.
Never have problems with the oilpan.
And the Europe style is OK ;)
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What shorter springs do you recommend?
The only shorter springs I can think of are Intrax but the drop would be much more extreme.
Also, while running 205/40/16, i'm just 1-2mm from rubbing up on the front strut inserts even with 15mm spacers. So to go to a 205/45 series tire might be pushing it. The rears have 8mm spacers now and the fenders are rolled as best as could be but if I hit a big enough dip in the highway at higher speeds (not even bottoming out), you hear the tire brush the inner fender. The good news is the rear suspension is where I want it to be already.
The Bekker drop hats are definitely an option but they are on backorder here in the U.S. - again, my gripes about this are purely from a cosmetic perspective. I love the look as is but lower would be nicer.
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IMHO - I think your decision will boil down to looks versus performance. Do you want it to look good or do you want it to work properly? I had a set of 17" wheels on my car and chucked them for factory 14 basketweaves. It looked cool, but the performance sucked. It has nothing to do with your situation, but the rotational weight of the 17's was off the charts compared to the factory wheels. I may be wrong, but the difference in height may be attributed to the springs being designed for a 325 engine weight. I personally wouldn't cut any springs to alter height.
Also - everyone repeat after me.....
Rims = motorcycles, bicycles
Wheels = autos
;)
Just some food for thought.
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I have a spare set of 15x7 koseis for performance :)
For now, I wanted some aesthetic appeal.
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Cutting a dead coil off ("dead" being one that is coilbound when the car's weight is on it) won't hurt anything, and is functionally no different than "get shorter springs."
Those that have mentioned shock travel issues are correct - if you lower the car too much & eat up all your shock travel, it'll bottom out harshly - but to my eye, you're not "there" yet.
Measure twice, cut once, though. I've not looked at an H&R "Race" spring, not sure what they have in the way of dead coils that you could cut. If you cut an "undead" coil, IE, one that is still an active part of the spring when the car is on the ground, your rate will increase - not necessarily a bad thing, as you're taking usable wheel travel away in the process.
Too many cars out there are lowered too much. This one does not look "too low" to me, I think a chunk of deadcoil could be removed without any issues. Maybe look to see how much travel you're currently using before cutting?
Putting bigger wheels on to fill the gap is going to raise the car (overall), hurt gearing, ehh, wrong answer, IMHO.
I guess if it were me, I'd A) measure from the center of the wheel to the lip of the fender (or something repeatable). B) Take spring off. C) Bolt wheel on car (car is on jackstands, duh), use a jack to move the wheel around. Put it back where it was on the ground - center of the wheel to the repeatable lip of fender. Jack it all the way up - measure. How much travel? Lower it, figure out where you want it, etc etc etc.
Lowering a car is not rocket science, but hacking springs up "this" much without any thought is not smart, either (I don't get the impression there are too many of "those" people here). That said, the H&R people certainly _DID_ engineer very carefully in their "race" springs, as they need to hit a pretty small target with those - lower quite a bit, don't overpower stock dampers, stiff enough to not bottom, not so stiff that the customers complain (they're nowhere _near_ real racing spring rates).
They've got a tightrope to walk. You just have to make yourself happy - the H&R "Race" springs are a really good starting point - I'd do all the measurements, cut some off, try again - just remember, it is hard to stick it back on:).
.02c
Iain (new here, owned a 318is for a few years, lots of experience messing with suspensions....)
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Before you cut them, sell them to me. Shoot me a good price and you have a deal.
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Deeper spring hats and no rubber pads. I ran without the pads for years and it did not seem to make much of a difference in noise with performance springs.
Uhoh, M42Club must be getting big. Arguments about style are breaking out....let's keep it friendly everyone.
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Cutting a dead coil off ("dead" being one that is coilbound when the car's weight is on it) won't hurt anything, and is functionally no different than "get shorter springs."
There are no dead coils on the front of the E30. The springs will be stiffer after being cut and heat affects can change their characteristics.
In addition, the suspension is getting into excessive negative camber (for the road) territory.
Putting bigger wheels on to fill the gap is going to raise the car (overall), hurt gearing, ehh, wrong answer, IMHO.
But he has the wrong circumfrance tyres on in the first place...
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There are no dead coils on the front of the E30. The springs will be stiffer after being cut and heat affects can change their characteristics.
In addition, the suspension is getting into excessive negative camber (for the road) territory.
But he has the wrong circumfrance tyres on in the first place...
What is wrong with a 16" tire on an E30? Do you mean width as in 205mm - 205/40/16?
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There are no dead coils on the front of the E30. The springs will be stiffer after being cut and heat affects can change their characteristics.
Even on the E30 H&R Race springs? Most of the ones I've seen do have several dead coils at the bottom of the spring.
A spring is simply a torsion bar in a coil; when the spring compresses, the wire actually twists. There are two things that affect spring rate - length of the torsion bar and diameter of the wire.
Most of the stock-location aftermarket "race" springs use a thinner wire and a bunch of dead coils to effectively shorten the active part of the spring (as once the dead coils are in coilbind, they no longer twist). This winds up with 2-4 coils of usable spring(torsion bar), thereby allowing for a thinner wire.
The heat certainly will affect the characteristics of the wire. That said, if there are dead coils (anyone have a picture of an H&R e30 race spring?), it won't matter - a dead coil is just taking up space. If there are no dead coils, ehhh, I don't think it'll hurt a thing - I've cut several sets of springs over the years (Audi 100 {old Audi 100} rear springs make great VW Rabbit rear autocross springs for those on a budget), I've had zero issues. Add that personal experience to the (literally) thousands of people who have cut their own springs, well, I don't think the heat-issue is truly an issue.
Is the "right" spring the right answer? Sure. Does the car know the difference? Nope. Not as long as the spring does not break.
In addition, the suspension is getting into excessive negative camber (for the road) territory.
Two things - negative camber does not kill tires, toe does. I've run as much as 3.5 degrees on the street; my inside edges _absolutely_ wore faster than the outside edges, but by the time the insides were done, the rest of the tire was close behind. Secondly, MacPherson Strut suspensions _lose_ negative camber (gain positive camber) as soon as the control arm goes beyond parallel to the ground - if the control arm is pointed "up" to the wheel from the body, it has less negative camber than if it were parallel.
The rear is another story - the rear does go far more negative, but he's not talking about lowering the rear more.
But he has the wrong circumfrance tyres on in the first place...
So? Stock size is 195/60-14, right? He's got a 205/40-16?
195/60-14 23.21" diameter
205/40-16 22.45" diameter
So, the difference is .76" shorter. Not bad. .38" difference in wheel gap (divide difference by two to figure out how much the car was lowered by the wheels).
That's not bad. Using a shorter diameter wheel can be _very_ good for handling - it reduces gear ratio, center of gravity, etc.
Don't forget that BMW spec'd a tire for the car's intended purpose - once you start narrowing it's intended purpose, things can change. Changing wheel and tire dimensions does wonders for performance - I'm currently running 275/35-15s on a 15x10.5" wheel on my autocross 2002 (which is street legal, fwiw), the enginerds at BMW certainly did not _intend_ for that much tire, and if the car does start tearing itself apart because of that much tire, I'll not complain - but the results are certainly worthwhile.
Dunno. I don't think there's any problem with cutting the springs. Are there better answers? Sure! Are there cheaper answers? Nope. Is it _bad_? No - not at all. As long as the car does not run out of shock travel, things will be OK. Would it be better to get shortened struts (cutting and welding or threading the strut tube), coilover sleeves and doing it right? Yup - but if he's happy with the ride quality & has the means to chop of a small chunk of spring, he should just cut the spring - he just needs to ensure that he's not cutting too much off.
It is not rocket science. Cutting springs is a bit crude, but it works - and in this particular case, I think it has merit - I think he could achieve all of his goals with a Sawzall without making any sacrifices.
Iain
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I'm currently running 275/35-15s on a 15x10.5" wheel on my autocross 2002 (which is street legal, fwiw),
Iain
Pics? Also what kind of drivetrain are you running to support those meaty tires? I didn't realize there were tires still made in those sizes.
Doesn't the wide tires sacrifice some of your steering, especially in an auto-x situation vs. road racing?
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Drivetrain is SP-legal - fresh bottom end/head, stock internals (balanced but not lightened), Megasquirt, Supersprint header, 2.25" pipe into a single chamber Flowmaster. Makes ~115 SAE corrected at the wheels.
I was using 13x9s with 225/50-13 Kumhos prior; the car got a bit taller with the bigwheels, but I lowered it more to compensate.
Steering response is better than the Kumhos. Grip is astounding, but it should be - we added a LOT more tire. It got a touch slower off the line, but that was never the car's strong suit to begin with - and now we have to slow down _less_, so, well, yeah, it works.
Not for the faint of heart when it comes to cutting sheetmetal, though - a LOT got removed. Need to get flares, do bodywork, etc - making it fast first, pretty later.
Iain
(http://www.fsp2002.com/images/bigwheels/070527-SCCA-AX--572.jpg)
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Holy cow! that's some crazy stuff right there. I like how you kept part of the front bumper to be legal. haha.
Since you seem to be more into racing, you should sell off those Euro Corners for extra cash for race parts.;)
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Heh, yeah, the bumper ends are back on - they have to be. I am allowed to cut fenders, bumpers and hoods for tire clearance - at the time of that picture, the fenders had been trimmed, but not the bumper ends - had to take about 2" off.
I have to have the bumpers on to be legal (in class, I can't say I care about street legality with that car - but the lights work, it has insurance & legal registration;), as well as the turn signals.
So, they'll stay:). I did not know they were cool - they were on the car when I got it.
Iain
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Even on the E30 H&R Race springs? Most of the ones I've seen do have several dead coils at the bottom of the spring.
Both H&R springs that I have used up front weren't like this. Maybe more hard core race springs are - I'm not familiar with them.
A spring is simply a torsion bar in a coil; when the spring compresses, the wire actually twists. There are two things that affect spring rate - length of the torsion bar and diameter of the wire.
But there is also a bending force too.
Two things - negative camber does not kill tires, toe does. I've run as much as 3.5 degrees on the street; my inside edges _absolutely_ wore faster than the outside edges, but by the time the insides were done, the rest of the tire was close behind.
I don't think you can say that camber doesn't eat tyres - but I agree that poor toe can also accelerate wear. When you see excessive inner (or outer) tyre wear, then the camber is not optimal for the type of driving being done. -3.5 degrees would be fine for track use, but the inner part of the tyres are taking a disproprtionate load most of the time while on street. You also loose sensitivity around the steering centre which is not always ideal for the road. You can get very close to the legal limits on thread depth before the outer edges catch up too.
Secondly, MacPherson Strut suspensions _lose_ negative camber (gain positive camber) as soon as the control arm goes beyond parallel to the ground - if the control arm is pointed "up" to the wheel from the body, it has less negative camber than if it were parallel.
That depends. If the front is in squat then you will increase negative camber. It also depends on the roll angles you get, back to springs and ARBs again. The possible target is to have zero camber at maximum roll.
So, the difference is .76" shorter. Not bad. .38" difference in wheel gap (divide difference by two to figure out how much the car was lowered by the wheels).
Compared to a 205/55/15 it is 109mm shorter in circumferance or 6.3% out.
Using a shorter diameter wheel can be _very_ good for handling - it reduces gear ratio, center of gravity, etc.
Agree on using smaller wheels for handling but gearing will be dictated by the tyre circumferance.
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That depends. If the front is in squat then you will increase negative camber. It also depends on the roll angles you get, back to springs and ARBs again. The possible target is to have zero camber at maximum roll.
No. Geometrically, if the suspension compresses on a Mac strut car, and the control arms go past horizontal, it is losing negative camber. No two ways about it. The outer ball joint travels a circular path around the pivot point of the control arm, and all else being equal, the car will have the _most_ negative camber when the arm is perfectly parallel to the ground. Anything beyond that, the bottom of the steering knuckle gets proportionally closer to the body of the car (it has to), which reduces negative camber. The strut is fixed, there's no way to compensate at the top.
It is an inherent "flaw" in MacStrut cars - they have lousy camber curves. Think about what happens when both front wheels are off the ground - it gets about 8 degrees positive camber.
It is not as dramatic a change as, say, a swing axle, due to the pivot at the ball joint and the strut, but by default, a macstrut car simply loses negative once beyond parallel.
Take a spring out, get a level/smartcamber gauge, start jacking and measuring - unfortunately, it is true.
Double A-arm cars are a different story; they typically gain camber under bump, which is why so many Hondas have 5 degrees negative.
Have the springs you've cut broken?
Iain
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No. Geometrically, if the suspension compresses on a Mac strut car, and the control arms go past horizontal, it is losing negative camber. No two ways about it. The outer ball joint travels a circular path around the pivot point of the control arm, and all else being equal, the car will have the _most_ negative camber when the arm is perfectly parallel to the ground. Anything beyond that, the bottom of the steering knuckle gets proportionally closer to the body of the car (it has to), which reduces negative camber. The strut is fixed, there's no way to compensate at the top.
Can't follow you with this one. I understand the balljoint moving in an arc, but I don't understand your connection to camber. Aaccept the point on the steering knuckle moving closer to the car reducing negative camber.
If we ignore the effects of roll of the car and steering angles for the meantime, starting from horizontal, as the control arm moves up the balljoint moves inwards. The strut compresses (and pivots slightly at the top) so the top of the tyre will have moved inward more than the bottom - so increasing negative camber.
If the arm could swing 90 degrees upwards, the tyre would be nearly parallel to the ground!
As the arm descends it continually increase positive camber - as you say, the wheels will have a very high positve camber when jacked off the ground.
Have a look at this : http://www.miracerros.com/mustang/t_animate_mps.gif
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The strut compresses (and pivots slightly at the top) so the top of the tyre will have moved inward more than the bottom - so increasing negative camber.
Yup. It did not make sense to me either, until I took a spring off and jacked the wheel through the travel, as limited by the strut.
Don't trust me, trust the camber gauge. There might be *slight* (incremental) camber gain at 0-1degree beyond horizontal, but I never looked at it _THAT_ closely - as the wheel begins to truly move through the available travel, it loses measurable camber. The strut can only pivot "so" much - the top of the wheel can only deflect inward (negative camber) a small amount, but the distance from the control arm pivot to the balljoint changes fairly quickly. I think you might be forgetting that the lower balljoint is going to move with much less resistance than the bottom of the strut moving toward the centerline of the car - the strut is going to stay relatively fixed, the balljoint is going to pivot outward as the c-arm moves upward - but the overall distance will not change appreciably; the outer pivot point is fixed.
If I have the spring out of the 2002 anytime soon (far, far more likely than the 318), I'll measure camber loss & post it, in degrees per inch of wheel travel. It is substantial. Look at the picture of my car above - not much lean, right? Look at tire deflection - the car is pretty fully loaded in that photograph.
The car has ~4 degrees of negative camber at rest in that picture - the wheel looks pretty much vertical in that picture. It also has a fair bit of caster, but the wheel is not turned very much. It is losing a bit of camber through roll, and the rest is going away through the suspension.
We could theorize for days. I'm not inclined to, I know what really happens when the c-arm goes past horizontal - it loses camber (the good kind).
Iain (want another brainteaser? If you have coilovers, and you want to redistribute weight to the rear of the car through ride height adjustment, would you raise or lower the rear ride height?)
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How would this explain why lowering a car increase negative camber? The more you lower, the more negative camber you get.
Also I have to think about your pivoting idea of the control arm as it is limited by the rear bushing. Perhaps the combination of all these things in an E30 gives rise to relatively controlled camber changes. The E36 has it slightly better again.
Your '02 seems to have a little bit of negative camber left!
I like these conversations as there is opportunity to learn something.
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How would this explain why lowering a car increase negative camber? The more you lower, the more negative camber you get.
The control arms are not parallel to the ground when stock - they're pointed down from the body to the wheel. The more you lower, the more negative camber you get - until the control arm goes beyond parallel.
Also I have to think about your pivoting idea of the control arm as it is limited by the rear bushing. Perhaps the combination of all these things in an E30 gives rise to relatively controlled camber changes. The E36 has it slightly better again.
The two pivots effectively act as one, as far as the balljoint is concerned. Depending on how the c-arm is attached to the car, the balljoint may move up and back, or up and forward as the c-arm rotates. Not all Macstrut camber curves are the same, and the E30/36 may well be better than a Dodge Neon, but no matter how it is sliced, macstruts lose negative camber once beyond horizontal - they all do (barring weird eccentric bushings which create an ellipsoid type curve - I've never seen that on a production car).
Your '02 seems to have a little bit of negative camber left!
I like these conversations as there is opportunity to learn something.
I like them, too. The 02 is set up just about right; still tweaking rear spring rates, but it is close. Unfortunately, the rules prohibit me from fixing the rear camber issue, but stiff springs cure that problem:).
Iain
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I like them, too. The 02 is set up just about right; still tweaking rear spring rates, but it is close. Unfortunately, the rules prohibit me from fixing the rear camber issue, but stiff springs cure that problem:).
When set up right, the '02 seriously handles. On the tracks days over here, there is a fairly scruffy race prep'd '02. The things hangs on like something you wouldn't believe (well I wouldn't :p). It has something like 127bhp but will lap faster than an E30 M3.
http://www.bmwcarclubireland.com/gallery/displayimage.php?album=random&cat=8&pos=-2567
http://www.bmwcarclubireland.com/gallery/displayimage.php?album=159&pos=31
Here's me not showing much negative camber!
http://www.bmwcarclubireland.com/gallery/displayimage.php?album=47&pos=191