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I went on a track day yesterday at bedford autodrome in the e21 and had a great day, the did well and held its own, but it has brought up some issues that need addressing

First off towards the end of the day i started getting oil starvation issues the oil had thinned out during the day and even though i had been keeping an eye on it it had to give in an hour early so i didnt wreck the engine

So im thinking sump baffles and oil coole, the cooler is easy enough but has anyone had experience with getting baffles fitted can you buy the parts off the shelf? do they have to be made? And how much clearance is there if any??

Next up suspension

I was pretty happy with the spax kit but i suffered quite a bit of understeer and a little waywardness at the rear so im a little more adjustment is needed camber at the front and rear?

Anyone know anything about these - 321588740760 (ebay item number)

Also where can i get the weld in kit for the rear?

The bigger thing though is the diff, do i go for a standard lsd and have it rebuilt, aftermarket quaife etc or the e12 sideloader option?? Pros and cons anyone?

Also anyone else have any good ideas that might be worth looking into?

Cheers
Si.

Tyres make the biggest improvement. Get some track tyres

Oil cooler should be enough, i dont think your going to need baffle s. Baffling your sump requires some welding in of plates and one way door etc.

The suspension top mounts look like a bargain. I paid 200+delivery for the rpm ones. A -1 degree at the front makes a massive improvement on mid corner grip.

Other items are just chassis stiffening upgrades? And lightening the car.

you need 4.1 or 3.91 standard rebuilded LSD for stock engined track use ...
upgrade ARB (if you upgrade only rear ARB, you will get more oversteer)

but first of all, get harder rear axle bushings (or fill regular ones with glass glue. that should improve rear end stability when exiting the corner, and stop shimmy rear end)
upgrade all bushings to stiffer ones.

Not having your full setup fresh in mind so bear with me but here are some thoughts

- Oil starvation issues: how did you notice? Did the oil pressure light come on? Oil pressure drop or oil temperature problem? What oil are you running? What model oil pan are you using?
It will be good to have oil temp and pressure gauges and place a bright 2nd parallel oil pressure warning light in top of the dash so you won't miss it. In E21's it's tucked way too much.

- Suspension: defo tyres, Toyo R888's? And I'd look for some bigger anti roll bars as suggested indeed. What are you experiencing at the rear then, and when? What brake setup do you have, and how is it balanced F/R, ever tested?

- As for diffs, think I'd go either regular plate LSD or OS Giken 2-way diff that is able to respond differently under different loads making it much more predictable in the wet and allowing up to almost 100% limited slip without the backdrafts. Our sponsors Hardeman specialize in them. No experience with Quaife, apparently they have lovers and haters just as well.

Ok heres a brief spec of my car to help out

Engine - m20b25, high comp engine, wild spec 300deg cam, 6 branch manifold, custom exhaust, light flywheel, good clutch.

Suspension - -60mm spax adjustables, completely polybushed, standard arb's front and rear

Brakes - rear disc conversion (standard 323) front 323 calipers blank discs ebc red stuff pads, stainless lines throughout

Tyre - i used Nankang NS2 - R track tyres budget road legal rubber but i was pretty happy

As for the oil starvation it was only on hard cornering i was getting the light flickering on and when checking the oil it was clear to me that it had thinned out, so an oil cooler is going to be a definate purchase the reason for baffling the sump is mainly because id rather be over prepared and its a pretty cheap mod i have a mate who is an expert ally/tig welder a sump should be pretty cheap i just need to know where or if i can get the plates etc, Gauges are going to be another definate upgrade.

I reckon ill probably go for those camber plates, but does anyone know where i can look at some uprated arb's? Then ill go get it properly setup and then test again before going any further

As for the diff, this is also a road car that i use alot and drive everywhere including abroad so i dont really want anything to harsh i was thinking maybe a rebuilt standard lsd with the ramp angles increased a little bit, but what ratios are available for a road car 4.1 is going to be way to short

Cheers for the input any more ideas/thoughts would be great

Oil pan: shouldn't be too hard, depends on what oil pan ur using but ready made solutions available

What oil are you using? full spec please...

ARB's are rare but available: http://www.amazon.com/ST-Suspension-520 ... B007BMJX08

Bloody hell i spent ages looking for arb's but couldnt find anything except a kind of add on arb for the front by whiteline.....but

I think i have a plan,

1 - Get a diff sorted

2 - front camber plates and setup then see whats what

If it still needs more i think it will be taking the 'lean' out of it and i think im going to do that with uprated spring rates which may mean turning my new shiney spax adjustables into coilovers but i think itll be the best way to go

As for the oil an m20 sump with a small wing to help with oil sloshing up the side of the block and a baffle and a mocal cooler should be more than enough

Currently it runs on mobil 2000 10/40 fully synthetic

While the sump is off im also going to replace the big ends and mains and get some arp rod bolts in there

After all that i should have a good strong reliable bottom end that i can beat on and take some revs for when i get my itb's

10/40 for track use not good.

I'm using Motul 15W50



temperatures reach 120 max on 15-20 minute hillclimbs (hard).

Using a M20 oilcooler from a E30.

That's why I asked! Oil cooler and a W50 oil or higher, my current favorite on engines with conventional valve operation is Mobil1 Extended Life 10W60, otherwise Castrol TWS Pro 10W60 would be quite ok as well and I believe Motul has a 300V in this spec too.

You haven't got front camber plates? Lol.

When you dial in some front neg and a quick rack the steering and front end grip is improved by miles you'll be like how the he'll did I drive this thing?

You might also want a alpina type lower strut brace, you can flex the area the arb mounts by hand (or rather swinging of them on a 4 post)

Some camber mounts, ground control are the bollox but the RPM ones are good value

Fit some rear camber/toe adjusters to the sub frame and use rear beam poly mounts and flip them left to right then get a fuel geo set up.

You probably will find a lot of play in your pedal box linkage so worth checking that.

Tyres, GEO and confidence in the middle pedal make the biggest difference, even setting up race cars we gain most time from the geo tweaks.

M20 oil starvation is common on e30 racers, look for an m20 windage tray/crank scrapper, I think they are made by ira Johnston in the US

[quote="Jason_323i"][/quote]

totally agree on everything !

I was talking to a couple of guys on the day and they said they previously issues with the mobil thinning out and not lasting the course so ill be looking into changing that for sure

Im definatly going with getting the geometry setup before anything else

As for the alpina lower front strut im going with the cheaper option and going weld in a bit of square bar across/near those front arb mounting points should do the trick

Ill check into the pedal box linkage aswell i was already considering looking at that to see if there any play/flex in the brake system, has anyone ever found any under hard braking?

si. wrote:
As for the alpina lower front strut im going with the cheaper option and going weld in a bit of square bar across/near those front arb mounting points should do the trick

cheaper option, copy it

http://s0.mojalbum.com/15399530_1757851 ... 739857.jpg
http://s0.mojalbum.com/15399530_1757851 ... 739859.jpg

Mobil or Motul you mean? To me and after several oil sample analyses Mobil1 EL looks like one of the very few decent options for M88, S14 and S38 engines these days and I'm considering to use that in the M20 as well.