Spec E30 Philosophy

#1

At VIR a few weeks back, I found a car with no wipers, and several cars with relocated batteries. I spoke to the owners and builder and they agreed to put the parts back on/back to the proper position.

Will a painted caliper make the car faster? Of course not. But the basic philosophy of Spec E30 is to leave it as it came from the factory, unless it is specifically allowed in the Rules. If something is discovered that is illegal, it will have to be remedied.

If you are building a car or have built a car, or are having a car built for you, keep this basic philosophy front and center. It will eliminate having to "undo" something in the future.

Also, at Mid Atlantic weekends, we’ll be checking diff lockup at all races (should be 22-36 lb/ft according to Korman) as well as AFM bore sizes. We’ll also swap a few DME’s with the "contol" units.

And I forgot to do the BimmerWorld brake pads drawing at VIR in March. I’ll do that next week.

Carter

#2

Carter wrote:

[quote]At VIR a few weeks back, I found a car with no wipers, and several cars with relocated batteries. I spoke to the owners and builder and they agreed to put the parts back on/back to the proper position.

Will a painted caliper make the car faster? Of course not. But the basic philosophy of Spec E30 is to leave it as it came from the factory, unless it is specifically allowed in the Rules. If something is discovered that is illegal, it will have to be remedied.

If you are building a car or have built a car, or are having a car built for you, keep this basic philosophy front and center. It will eliminate having to "undo" something in the future.

Also, at Mid Atlantic weekends, we’ll be checking diff lockup at all races (should be 22-36 lb/ft according to Korman) as well as AFM bore sizes. We’ll also swap a few DME’s with the "contol" units.

And I forgot to do the BimmerWorld brake pads drawing at VIR in March. I’ll do that next week.

Carter[/quote]Where in the heck would someone move an E30 battery to?

#3

I was wondering the same thing. Where else would you put the battery?

Michael O.

#4

In the inside of the car, usually next to the driver to balance the car.
Painted calipers? Damn, I have to undo that, but they look so cool. But if we have to leave the car as it came from the factory, then colorful painting/graphics are not oem either, I’m just being picky.:wink:
Is AFM the air flow mass inlet diamater?

#5

BETO wrote:

[quote]
Is AFM the air flow mass inlet diamater?[/quote] Yes

#6

BETO wrote:

[quote]Painted calipers? Damn, I have to undo that, but they look so cool. But if we have to leave the car as it came from the factory, then colorful painting/graphics are not oem either, I’m just being picky.:wink:
[/quote]

Agreed, we are down to restricting "decoration" on a brake caliper but allowing graphics anywhere else on the car? Who’s painted their bumper? That’s not spelled out, who’s pop-riveted a large piece of sheet metal on the roof? The rules say that the panel should be "welded/bonded" AND flush with the roofline. I could care less how people do it, especially to reduce cost, but as some point, it’s getting a bit nit-picky.

I understand the philosophy but using caliper paint as an example is a bit over the top.

#7

erupert66 wrote:

[quote]BETO wrote:

[quote]Painted calipers? Damn, I have to undo that, but they look so cool. But if we have to leave the car as it came from the factory, then colorful painting/graphics are not oem either, I’m just being picky.:wink:
[/quote]

Agreed, we are down to restricting "decoration" on a brake caliper but allowing graphics anywhere else on the car? Who’s painted their bumper? That’s not spelled out, who’s pop-riveted a large piece of sheet metal on the roof? The rules say that the panel should be "welded/bonded" AND flush with the roofline. I could care less how people do it, especially to reduce cost, but as some point, it’s getting a bit nit-picky.

I understand the philosophy but using caliper paint as an example is a bit over the top.[/quote]

One could make the argument that painted calipers is more than just decoration.

Painted calipers give you the ability to quickly see if you have any leakage while at the same time giving you higher contrast between your caliper and pads… so it’s kind of a safety thing :whistle:

#8

The rules say you can install Graphics. That is the difference.

Michael O.

#9

Painting calipers is illegal? Are we being serious? :huh:
So if I paint my ugly, chalky aluminum bumpers black or body color I’m illegal?
Paint the letters on my valve cover?
Are these really the battles we want to wage regarding rules?
Carter, I’m with you on modifications that alter the location, function or weight of something, but paint?

#10

Carter, have you checked your rebuilt diff? At 22-36 ft-lbs it is my experience that you will DQ the entire field.

Used differentials that I have checked are in the 40-44 range.

Having said that, give us all a number and it will be conformed to.Same for front camber, please.What is the AFM bore size that you want to check for? We will purchase a ID caliper to check them (I’ll check mine to determine bore).

I’ll put Cullen to work, either gathering data or checking numbers at Robeling in May. May I suggest data collection first?

Regards, Robert

P.S. I checked a diff this weekend to show one how it can be done. I’m sure there was nothing going on with the diff. The number was 52 ft-lbc.

#11

Once again I posted without context.

I dont know how the Korman 22-36 ft lbs is derived.

To get the goober-in-the-field torque readings, here is what you do.

  1. Jack up passenger side of car.
  2. clutch in neutral, parking brake off.
  3. With your torque wrench set torque to 40.Does it click when you attach it to a lug nut and "tighten" the passenger side rear wheel?Move up 5 ft lbs. Click, or does the wheel spin? Hone in on the click versus spin number.

Regards, Robert Patton

#12

9.3.11.3. Welding to create a "locked" differential is permitted.

Am I missing something here? If the above is allowed why does it matter how limited your slip is?

Respectfully,

Jeff

#13

There are coatings that allow a faster rate of heat disipation into the air. Can I "paint" the pistons in my engine with ceramics for instance? I wouldn’t care if it was just paint or even temp sensitive paint. But if they do it, it better be cosmetic.

Diffs

My car will not have the problem with spinning the inside tire like the 325, but I don’t understand why you’d want to limit it to a stock only setting that will wear the diff faster and create more heat. After watching the cars especially in the rain at VIR they seem to spin the inside rear alot. I’d really consider that a preperation modification for racing as the cars have more grip and different tires than what the factory offered.

#14

Patton wrote:

[quote]Once again I posted without context.

I dont know how the Korman 22-36 ft lbs is derived.

To get the goober-in-the-field torque readings, here is what you do.

  1. Jack up passenger side of car.
  2. clutch in neutral, parking brake off.
  3. With your torque wrench set torque to 40.Does it click when you attach it to a lug nut and "tighten" the passenger side rear wheel?Move up 5 ft lbs. Click, or does the wheel spin? Hone in on the click versus spin number.

Regards, Robert Patton[/quote]

One must figure out the true value the torque wrench indicates by using the formula found here.

http://www.specialpatrolgroup.co.uk/spooky/torque/torque.html

I’m guessing the adapter length would be 50mm due to the 4X100 bolt pattern.

#15

Jamie thanks for the torque info.I dont know if my goober-in-the-field test is valid 'cause I could not follow the math.I’m certain Carter will flush-out a valid test procedure.

Jeff, you’re going to have to drink more of the spec e30 kool aid.I think.

Without the rules in front of me, the wording goes something like what you said, locked differential or factory specifications.So it is necessary to provide factory documents to show the racers the factory number.I’ve heard stories about factory options so we’ll have to see how this plays out.Oh yes, remember that diff lube is free. Does the non-slip lube make a difference?Hot testing? Cold testing?

As I have been reminded, the Bently manual is not the factory specification source. Ray Korman will be a great resource,but he is not the factory specification. I’m under the assumption that the factory lock percentage was/is 25% lock up. So, is that 25% of the engine’s rated torque of 162(?) ft-lbs, or 40.5? And, as Jamie showed, is that 40.5 with the good ole goober-in-the field torque wrench?

Time will tell.Clarifications will follow.

Regards, Robert Patton

#16

http://www.realoem.com/bmw/showparts.do?model=1113&mospid=47309&btnr=33_0014&hg=33&fg=05

Says 25% on realoem.com

Jon

#17

How far is all this diff checking business going? I ask as a participant and a builder of customer cars for the series. I am no means an expert on differentials but I do know there are three basic settings: initial lock, lock % from acceleration and lock % under deceleration. My concern is the grassroots origin of this series and the consequent builds which populate it.

There are many factors that influence the three settings listed above. Al Taylor was good enough to source me an LSD to replace the open unit in our car now. I have no idea the maintenance history or how long or where the replacement unit has been sitting. What I do know is it locks more than what I have know which is a good thing for me. So what do I have and how will the "test" numbers turn out? Well, the diff has who knows what wear and tear, deposits (ie rust or misc "Taylor funkage") on the LSD component itself and who knows how the MOTUL gear oil friction properties effect the locking action vs the factory recommended fluid.

Any way, quick food for thought as I have to end this to run to a meeting. Talk amongst yourselves…

#18

I’ll put Cullen to work, either gathering data or checking numbers at Robeling in May. May I suggest data collection first?

Regards, Robert

P.S. I checked a diff this weekend to show one how it can be done. I’m sure there was nothing going on with the diff. The number was 52 ft-lbc.[/quote]

Matt, the above is from an earlier post. However, between the field at CMP and Robeling Road in May, the administrators could collect data from the majority of all active spec e30 racers. Like the data on horsepower that was collected at the nationals last year, those that oversee the rules can give us a determination on differentials.

Camber too?

AFMs too? (Should not be any deviation on this one)

Are there other checks and balances that need to be looked at?

Regards, Robert Patton

#19

Wow, this series is getting serious huh? While we are checking things why not take fuel samples? Why not have a stock of ECM’s that you assign to each car at each race like NASCAR does with wings and tires. Are you going to check injectors? Pull apart engines to check pistons?

If you allow welding of the diff to create a locked diff. Why the bother for checking lock up at 40 ft/lbs?

#20

badboypolar wrote:

I don’t care either way, but it’s a lot better to have a LSD with a high (higher than stock) locking percentage than a welded open diff.