Just wondering how much rake you guys are running, and where you're measuring.
I was told I want 0.75" measured at the Tow Hook points - but the car is acting like it has too much rake (transitional oversteer, mid corner push that becomes oversteer on exit).
Thanks!
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
Turner recommended 0.5" for my setup. I've increased it a touch since, and IIRC am pretty close to 0.75". My car is pretty damn neutral, with sometimes slight understeer, and sometimes slight oversteer. But it's FUN with no surprises. I can get mid corner push unless I'm very patient with the throttle or very aggressive with the throttle.
I measure at the tow hook also. At least it's repeatable and consistent between cars.
Interesting, ok thanks.
Obviously, 3/4" rake at the tow hooks is very different than 3/4" at the end of the rockers.
Thanks!
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
I find with less than about an inch of rake (at the rockers), i really have to jack up the front and slam the rear. What are you all's F/R ride heights along with your rake?
.5-.75" rake on e36 seems to be the sweet spot, depending on your suspension setup. I would not go less that .5" rake. Always measured at the jack points. I think our height is around 5" at the front jack point to the ground.
I also run about .5-.75 measured at either the rockers or marks I have on the side of my car that I use for reference when I align, scale, etc.
How is your car on turn in? You mentioned pushing mid corner then turning to oversteer on exit. If you get rid of the push on entry (if it's pushing and it probably is) and mid corner, the car will likely work much better on exit.
I'll go home and measure this evening, at the tow hook points.
That said, I was asked this question yesterday, but told to measure to the top of the side skirts, right by the wheels.
Front was 9-5/8 rear was 11-1/8.
I'm running 275/35 R17 hoosiers; the spec says they are 24.8" tall (new).
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
I wanted to add, there's also something odd going on in the front end. I have a 328, with offset lollipop bushings (installed bearing outboard), and GC camber plates.
When I switched to M3 control arms (for better caster) I could get only about 2* of camber.
Something (else) is clearly wrong - I didn't start a thread on that problem - I just wanted to know whether my rake was wrong. It sounds like the answer depends on who you talk with... Some use tow hook points, some use rockers - but all say 0.5 - 0.75. Where you measure makes a huge difference.
I'll go measure at the tow hooks tonight.
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
Not tow hooks ... the jack points on the underside of the car, behind front and in front of the rear wheels. Measure from floor to jackpoint (without the rubber pad in place). Ours is ~5.5" in front, and ~6" on the rear jack point.
Edit, unless you mean the J-hook tow hooks that you strap the car down with ... then, yeah .. those points
Last edited by ScotcH; 08-09-2017 at 01:10 PM.
Right, I said 'tow hook' also, and meant the jack points on the side of the car. Ug.
I have a 328, not an M3. The factory 328 arms are much like the 95 M3 arms, in that you don't get much caster from them. In fact the spec is wildly different between the two (328 vs M3).
Anyway, on my stock arms (again not M3) the balljoint is much wider and the Ground Control rollcenter correction takes advantage of this by moving the balljoint outwards for more camber.
Even with that balljoint oriented towards the outside, and with camber plates, I can get about 3.5* of camber max. I can get only 6* of caster, and you may find another post on the subject
So, something is wrong. What it is, I have no idea.
My complete front parts list (328is, not M3):
1) stock 328 arms
2) GC lollipop bushings, offset
3) GC rollcenter correction, offset outboard
4) GC camber plates
I also have MCS double/remotes and GC swaybars, but neither affect camber/caster.
I'm starting to wonder if I somehow have the camber plates installed incorrectly - however the shock top is oriented as expected about 1 O'Clock on the passenger side, and 11 O'clock on the drivers.
For completeness, I tried to put the 96+ M3 control arms on the front - but lost a ton of camber. I stuck with the offset lollipop bushings, which we know is wrong - but no way should I have been able to get only 2* camber with camber plates.
- - - Updated - - -
Right, I meant the oval holes under the rocker panels, where you attach the T-Hooks when towing. They are maybe a foot from the wheel wells. Under the plastic circles you pull out for the jacking point (if you have one which I don't).
Last edited by CoMZ302; 08-09-2017 at 04:03 PM.
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
I've often wondered if something isn't amiss on my 95 M3 also. Stock LCAs. VAC LCABs (which provide close to stock caster or maybe a touch more). GC street/track camber plates, but I have to add washers to get -3.5 camber even with the camber plates maxed. My caster is aplenty thought, at ~7.5.
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
Odd question, but do you have the upper strut reinforcement plates installed in the car? I did and it was severely limiting my camber. I had to cut a notch in the strut tower to allow full movement of the camber plate. Just throwing it out there.
Thanks for the great idea. I have those plates but have not installed them yet.
Time to post some pix, just a sec.
- - - Updated - - -
Driver's shock tower close up.
Passenger lollipop
Passenger outer tie rod (GC) and balljoint (offset GC).
The Driver's shock top- to the left is the firewall, top is fender, right is grill, bottom is engine.
for some reason the other two pix are upside down.
- - - Updated - - -
I've attached some pix -I think they're correct but let me know if you see something wrong.
Last edited by CoMZ302; 08-10-2017 at 10:18 AM.
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
That is about right for 95 m3's. When I had a 95 I could only get about 2.5 with just camber plates and no shims. 96+ you can get up to about 4 without shims.
I just noticed that you have a 328, not an m3. I think that there might be different spindle geometry, so if you still have the 328 spindles, that could be limiting your camber. I am pretty sure they have less camber stock than an m3 whether 95 or 96+ and the 328 strut mounts are centered which is the same as a 95 m3, and a better position for camber than the outboard 96+ strut mount setup. the spindle would have to be the difference.
Last edited by tsmith25; 08-10-2017 at 04:03 PM. Reason: reading comprehension then respond...
95 cosmoschwartz M3/2/5 : 2012-1/1/2014 (worn rtab's and bald rear tires in the rain)
98 cosmoschwartz M3/4/5 : 2016-3/10/2017 (understeering SUV)
99 Estoril M3/2/5: 6/16/2017-current
Maybe I'm crazy. But I've had a 95 m3, 96 328 and 94 325 all have had no issues getting over 3* with any of them. Like someone said earlier if there are reinforcement plates in there it will limit camber.
- - - Updated - - -
all looks right. I'll take a look at my shock tower tomorrow and see how my shock tower looks.
Anyone who's still following this
My actual measured rake, at the "t-hook" points, is 1-1/16"
Many folks on here have suggested rake (at those points) should be 1/2" to 3/4"
A couple of active (and fast) NASA GTS folks have suggested 3/4" is correct
I went back to my BimmerWorld setup sheet for the MCS shocks, and they suggested 1/4"
With 5" rear springs, and the GC "articulating" rear perches, the least I can get is about 5/8" without raising the front.
Last edited by CoMZ302; 08-17-2017 at 10:37 AM.
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
For what it's worth, I just took a look at my numbers the last time I measured, but I raised the car (at all 4 corners) about 1/4" since I measured last. So I'm sure these rake numbers aren't 100% accurate. These are measured without driver. I'd just call this 1" of rake on my car.
FrntLeftJackPad: 8-1/8 FrntRightJackPad: 8-¼
RearLeftJackPad: 9-1/4 RearRightJackPad: 9-⅛
Great info - Do you like the way your car handles?
Mine, with that much rake, won't get off of the corners - instead of gripping and leaving, it just goes to oversteer. It's also not great in transitions as the rear wants to come around a lot.
Of course we all know mine's a 328 and something is wrong with the front.
2002 BMW M Roaster.
1998 BMW 328is SCCA E Production road racer.
I do like the way it handles. In steady state (long constant-throttle corners) it's dead neutral. On corner exit I can 'easily' get throttle oversteer on 2nd gear turns. On 3rd gear exits under full throttle, I can feel the rear end 'set' out just a little (as if all the slack in the suspension is preparing for oversteer), meaning if I had more power, I could easily get manageble oversteer in 3rd gear corners too. I'd like it to be a LITTLE easier to rotate on trail brake entry, but it's all a trade off.
FYI, the car was predominately an understeer car until I moved the front UUC ARB from full stiff to full soft. That change really made the car balanced.
Rough numbers:
95 E36 M3 used for HPDE/instructor (not race)
Weight is OEM minus rear seat stuff.
-3.5 camber front, -2.5 camber rear.
0 toe up front, 1/8" toe in rear.
Toyo RRs.
TCK SA shocks.
550/650 springs.
Front UUC ARB at full soft, rear OEM ARB.
All bushings in the suspension are OEM except for the LCAB, which are VAC poly.
Last edited by aeronaut; 08-17-2017 at 11:26 AM.
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