Das Beast: My E30 track / street build

[dvallis]

Just ordered one of these beauties. Highly recommended by my Dad, who has built everything from V8s to massive 2 story marine diesel engines. Great for checking our rotating assembly during the build.

He laughed about the bearing trouble. Apparently when installing 3 FOOT diameter bearings on marine diesels, they would blip the compressed air starter and turn the crank after every one was placed ... just to be sure. :devil:

[dvallis]

More progress. Bottom end built, plastigauged, torqued etc. Spins nicely. Takes about 5 ft-lbs to keep moving. Stethoscope shows no suspicious metal on metal "tics", just the usual bearing & ring noise.



Car went to to the fab shop for full roll cage today. Gah, it's expensive! But worth the cost if you consider consequences of a cheap roll cage.



Also chose the body fab shop today, one mile from my house. They're good and also have a dyno. Guy wants to sell me a BMW M1 body kit that's gathering dust. Das Beast might get outrageous. :devil:

[dvallis]

Did way too much research on clutches this weekend. All the Sachs Racing parts are NLA or getting really expensive. (-765 240mm pressure plates, -867 240mm heavy duty clutch disks etc.) E34 M5 OEM kits are available, but then you have to get the stack height right, mess with throw out bearing etc.

In the end I decided on a Clutchmasters FX400 03010-HDC6. Great value for the money and lots of good feedback about it on R3v. Using with the stock single mass flywheel, refinished for $40 at a local shop. Should be a solid combination.

Here's a good picture. Input splines will be different for the E30 version.

[dvallis]

Nice refinished flywheel. Great job. Only cost $60 and took 45 minutes.

[dvallis]

Another quick project tonight. Deleting the throttle body heater line. Permanently. Here's the original fitting at the back of the block:



12mm x 1.5mm bolt from Lowes, sawed down to appropriate length.



Newly installed. Looks good.



Tomorrow we clay the engine and check piston to valve clearance. Valve drop test with a dial gauge was a dismal failure. Going with this method instead:

[dvallis]

So, really measuring what's going on inside the engine for piston to valve clearance is turning out to be a bit of a slog. First, here's what we THINK should be going on:

CAM has 1.5 mm more lift = 0.050 less clearance
Pistons are sitting 0.5 mm below the deck = 0.020 more clearance
0.140 head gasket = 0.070 more clearance

So ... there should be about 0.100 clearance.



To actually measure this we have to build the head, clay the pistons, slap on TWO stock head gaskets to approximate thickness for a MLS gasket, build the front of the engine .... and turn the crank.

Lapped the valves while we were there. Seats were precision cut by machinist:



I did not want to go through the whole valve spring compressor bla bla bla just to check clearance. Lowes sells "compression springs" for a few bucks each. They are perfect. Strong enough to hold valves up for testing, but you can hand compress them.



Here's one installed on a valve. Perfect!



Rest of springs on the head. Schrick cam in place.



Rockers and shafts installed. You get a good idea of valve lift turning the cam gear. It's a lot!



Almost read for the clay. Hobby Lobby special. :devil:



And ..... we were stopped dead in our tracks by the crank gear. It would not go on.

Gear fits fine over the M20B25 crank. Both cranks measure 32.00 mm, but for some damn reason this crank measures 32.10 mm at the front. Makes no sense at all, since the crank dropped nicely into stock bearings and rotates fine. It MAY be that all the torque we used on the crank bolt when the rods were jammed expanded the front of the crank. Fixing this will take a while. Can't remove the crank without throwing away ARP main studs, so it's a "repair in place" problem. Probably lots of work with metal sanding paper, not the Big Ass File. It's only 0.004". Patience .......

[digger]

the ARP main studs should be reuseable.

dont forget the oil seal spacer ?

is the end flared/mushroomed ? so it measures 32.00 near the bearing but 32.1mm at the end? that would take alot of force.....

the 284 cam should only reduce P to V by 1.0mm compared to stock cam as thats about the difference in lift @ 10* ATDC when contact is most likely. it will depend on how the the cam is set up e.g 2 degrees advance reduce clearance by 0.25mm inlet and increase by 0.25mm exh and vice versa with retard

[dvallis]

Hey Digger

I'm using a Schrick 0056 01 840-00 284/272. Their specs say lift is 11.4 intake, 11.0 exhaust, so 1.3 / 0.9 over stock, right? I called it 0.050 for both to be safe.

Thanks for the oil seal spacer reminder. We're just spinning the crank so this is all coming apart again. Decided not to fight with the spacer too.

Yeah, crank end mushrooming is a beatch. We did put serious torque on there so Mea Culpa. I think. I talked to ARP and they advised against re-use. Probably just conservative CYA, since they don't want engines exploding on their advice. Just going to deal with it and machine in place. Worst case its sand paper, pipe clamps and patience.

[hwy84]

Yeah, crank end mushrooming is a beatch. We did put serious torque on there so Mea Culpa. I think. I talked to ARP and they advised against re-use. Probably just conservative CYA, since they don't want engines exploding on their advice. Just going to deal with it and machine in place. Worst case its sand paper, pipe clamps and patience.

Can you heat the gear enough to get the clearance you need to slide it on? Maybe a stupid suggestion...

[dvallis]

I could, but when it cooled the damn thing would NEVER come off.

[dvallis]

Seats ordered. Two of these: Ultrashield Road Race Halo Lightweight, powder coated white with red stripe over black cover. I like the metal frame for crash containment. Cage fabricator has done many of them. Looks kind of strange compared to Sparco or Racaro, but fit me WAY better because it's custom made. Super comfortable.

[digger]

Hey Digger

I'm using a Schrick 0056 01 840-00 284/272. Their specs say lift is 11.4 intake, 11.0 exhaust, so 1.3 / 0.9 over stock, right? I called it 0.050 for both to be safe.

Thanks for the oil seal spacer reminder. We're just spinning the crank so this is all coming apart again. Decided not to fight with the spacer too.

Yeah, crank end mushrooming is a beatch. We did put serious torque on there so Mea Culpa. I think. I talked to ARP and they advised against re-use. Probably just conservative CYA, since they don't want engines exploding on their advice. Just going to deal with it and machine in place. Worst case its sand paper, pipe clamps and patience.

The peak cam lift has basically zero to do with piston to valve clearance as the piston is down the bore at that time. Peak valve lift is at ~110 ATDC for that camshaft, at that crank angle the piston is 63.5mm down the bore with 84mm crank and 130mm rod combo.

If you look at the lift at TDC this gives a better reference point as interference is normally around 10 degrees after TDC +/-5 degrees or so. Stock cam is like 1.25mm lift at TDC and the 284 is 2.2mm (on paper) so its about 1mm or 0.040 different. While in this particular case this is much of a muchness compared to 0.050 the prediction will be much better as a general rule. If you have a more aggressive cam you need to add a bit more to the TDC value as the valve opens up a lot quicker.

As an example the schrick 304 has 12.2mm peak lift which is about 2mm more than stock. If you compare the lift at TDC it is 4.0mm which is 2.8mm larger than stock (1.2mm). So you loose about 2.8mm P to V. its probably closer to 3.25mm at 10degrees ATDC as the 304 ramps up slightly quicker than stock so adding 0.5mm is recommended but that is a good estimation.

On the exhaust the clearance is lowest about 10 degrees before TDC give or take.

[dvallis]

Awesome post. Thanks for the info. Completely makes sense.

[dvallis]

Crank refinishing

So, how do you take 0.003 off the end of a crank? Here's my DIY solution.

Step 1: 100 grit sandpaper from the local hardware store for $4. Cut a strip and tape around the crank.



Step 2: Grab an old E30 radiator hose. Cut as shown. Clamp to a hole saw in your strongest electric drill. Slide the other end over the paper and clamp. Not too tight. Start grinding. In about 15 seconds you will have taken off 0.001! Go slow, measure often, testing the crank gear for fit. Change paper. Repeat. Be careful as it generates a LOT of heat.



Five minutes later the crank gear fits.



Had to hog out the spacer groove a bit to match the crank keys.



Spacer pressed on. Fits perfectly now.



Here's the final assembly. Worked out fine.



Almost ready to clay the pistons and spin this thing.



Clutch arrived. Should get the job done.



Final pic. Roll cage is in progress. Fabricator is a total Artiste. She let me take this picture then said "Get the heck out! I need my space!" :devil: This will be the main roll hoop.

[digger]

if thats a pressed intermediate shaft gear id order a sintered metal version for the final assembly