Ultra Light 2.2L m10 Turbo Build

[shauer]

Check your clearance between the rods and the side of the crank case. I had to grind out a little of the boss on #1 to clear. This is highly dependent on the dimensions of the rods. Mine was using stock S14 rods, yours will most likely be different and might possibly clear without any grinding needed.

Location of interference painted white in this photo:


- Steve

[jrcook320]

Quick question: Why dual valve springs for this build?
Thanks!

I'm revving to 7k with a cam - valve springs are a must. I'd rev to 8k if I could afford the rockers for it (but I can't). The higher the lift for a given duration, the more aggressive the acceleration of the valve will be. This cam has pretty high lift for a 284. Also, according to TEP, single HD valve springs don't offer as much valve control for a given seat pressure as dual springs. They have a great deal on SS valves and dual spring combo that I can't turn down.

- - - Updated - - -

Check your clearance between the rods and the side of the crank case. I had to grind out a little of the boss on #1 to clear. This is highly dependent on the dimensions of the rods. Mine was using stock S14 rods, yours will most likely be different and might possibly clear without any grinding needed.

- Steve

Thanks Steve. I remember that from your build. I need to get my crank ground and block machined before I can check final clearance.

[gsumzzz]

Holely molely jr, when did you get time away from wife and kids to clean the inside of the block! Cannot wait to see the finished product. Nice work and Good Luck!

[TheBestCow]

Any plans for the old turbo setup?

Looks amazing. Can't wait to see more.

[vtgti]

You aren't scared of using the high lift cam with the factory rockers? Or is it just longer duration, but with factory lift?

[Tom D]

I'm revving to 7k with a cam - valve springs are a must.

this always makes me smile. one cylinder fires 117 times a second, amazing!

http://youtu.be/ISd6JbHSx1M

http://youtu.be/vcyT18qk8lsl

[e21Terry]

Putting myself at great risk of being accused of blatant one-upmanship I offer this...







Don't put that grinder away just yet. Color is Pontiac blue, closest I could get to Baltic blau.

PS I'll do one for Lightsmith if he ever makes good on his offer to detail my undercarridge.

[Tom D]

jr, I think you might have made a mistake by grinding down the main bearing trusses. I have always believed that BMW casted them deliberately to aid the main bearings and block stiffness, not as the byproduct of the casting process. look at the shape, I don't think they would have gone to that detail on something that will never be seen.

I removed some un-used bosses, as well as cleaned up some rough edges in the crank case to improve oil shedding.

[jrcook320]

You aren't scared of using the high lift cam with the factory rockers? Or is it just longer duration, but with factory lift?

Per VAC (or schrick), rocker stress isn't considered a problem until you get above 328* duration. Most cams will typically have both longer duration and higher lift, with the exception I've seen being "cheater" grinds that have stock duration with higher lift to be racing class legal (not my thing). There is a limit to how much lift you can get for a given duration due to limitations in the rocker pad geometry and valve/rocker acceleration (ramp rate). If you've been around any american V8's, you'll see significantly better cams available for roller rockers because a roller rocker allows for more aggressive ramp rates. The increased ramp rate of a cam is the reason most cam grinders recommend valve springs with their grinds to prevent float. Valve springs that are too stiff can result in excessive valve train wear, so there's a balancing act between too light and too stiff. I haven't done much research regarding optimum seat pressure yet there, I'll talk more to TEP when I get there.

I don't want too much duration because I don't want to loose any midrange efficiency, so one way to maximize flow is to maximize lift for a give duration. Assuming grinder's published specs are accurate, the Elgin cams seem to be a cut above the rest in that regard.

Putting myself at great risk of being accused of blatant one-upmanship I offer this...

Don't put that grinder away just yet. Color is Pontiac blue, closest I could get to Baltic blau.

PS I'll do one for Lightsmith if he ever makes good on his offer to detail my undercarridge.

Thanks for the photos. It looks like I have a little more work to do. What block is that? Your internal gussets appear to be a bit beefier than mine. Mine is a 1.8 block.

jr, I think you might have made a mistake by grinding down the main bearing trusses. I have always believed that BMW casted them deliberately to aid the main bearings and block stiffness, not as the byproduct of the casting process. look at the shape, I don't think they would have gone to that detail on something that will never be seen.

I didn't grind them down or reshape them as they are certainly there for structural rigidity. I simply removed the rough edged casting parting lines along the gussets which are stress risers as well as hold oil, sludge and/or grit. I didn't spend much time on the interior of the block. I still plan to smooth the head oil drain inlet in to the block, as well as smooth a few more things down.



Also, notice I drilled a small hole in the webbing at the bottom of the block under the starter. This area always holds water and it used to bug me. Now it should mostly drain naturally.

[e21Terry]

The block I posted is an earlier 2.0 block. The last time I was inside a 1.8 I do seem to recall that the block skirt gussets weren't as full. This does seem to lend some creedence to 1.8 blocks being lighter castings. I'll weigh it and post. As for the exterior smoothing, I've been to too many street rod shows and seen too many beautifully detailed engines. The practical benefit is exponentially easier cleaning. Sometimes I think my middle name should have been overkill.

The 2.0 block is 92.5 lbs (6.6 stone) as weighed on uncalibrated, untraceable to NIS, bathroom scales. Good for me that the wife didn't catch me.

[FranzE21]

Quick question: Why dual valve springs for this build?
Thanks!

High lift and dat boost.

[e21Terry]

First, full disclosure: I have no experience building or operating a boosted engine, so take this FWIW to you.

From what I have read, cam theory says that because cylinder pressure in a boosted engine produces useful work through more degrees of crank rotation than a na engine, a cam with a later exhaust valve opening can be beneficial. Also, in general, increasing the exhaust valve size will help more than increasing intake valve size.

Just stuff I remember reading, but it seems logical.

[jrcook320]

Getting the head ready for new guides, valves, and a 3 angle valve job:

[jrcook320]

Has anyone ever shortened their valve guides? I've seen in mentioned as a method for improved port flow. I'm planning on thinning and shaping the outside of the guide where it extends in to the port, but wondering how much value there is in shortening them.

[shauer]

Has anyone ever shortened their valve guides? I've seen in mentioned as a method for improved port flow. I'm planning on thinning and shaping the outside of the guide where it extends in to the port, but wondering how much value there is in shortening them.

I'm pretty sure MM does this with their sport heads. I'll look through my pictures when I get home tonight and see if I can locate a picture of my intake/exhaust ports on my MM sport head to see if that gives any idea of how much they shortened them.

- Steve

- - - Updated - - -

For what it's worth, this is what MM does. It looks like they might shorten the guide on the exhaust maybe a little but on the intake it looks like they taper the guide instead of shortening it.

P1010280.jpgP1010279_edited-1.jpgP1010277.jpg

- Steve

[jrcook320]

Thanks for the photos, Steve. That's an interesting port shape in the intake. I'll likely just taper my valve guides like that.

Per my Thrust-bearing-journal-machine-shop-fail thread, I've found that my thrust journal on my crank is too wide. I've measured exactly 30.556mm with a bearing width of 30.366mm.

I measured my end play last night with a dial indicator and I get exactly .008". Again, BMW's spec is between .003"-.007". It is noteworthy that I was measuring in the bitter cold around 0 degrees in an uninsulated garage. I calculate that the block itself will expand by about .0005" on the thrust width if I had been measuring at 70 degrees. I'm not sure how the crank would expand, but I would think my clearance will reduce overall by as much as .001" at a reasonable ambient temp. I might lug the whole thing down to the basement and double check after it warms up before making a final decision on whether or not

I slid one piston in and measured .030" of side clearance on the rod journal. I don't have a spec for that, so I have no idea how important that is other than I know my rods are narrower than stock. The piston comes up out of the hole by about .026" which is pretty consistent with the .006" the machine shop took off the deck. The good news is that confirms a lot of things about the build that I've had an uneasy feeling about until I saw it with my own eyes (the accuracy of stroke on this custom crank and this piston/rod combo, etc).

It also looks like I wont have to do any clearance grinding on the crank case for throw clearance.

[shauer]

Thanks for the photos, Steve. That's an interesting port shape in the intake. I'll likely just taper my valve guides like that.

It also looks like I wont have to do any clearance grinding on the crank case for throw clearance.

"Interesting port shape" yeah, let's just leave it at that. If I had to do it over again I would have had my local shop do their "common sense" porting on the head and saved some $$$ over MM.

I have seen a 2002, 2.0L E21, 1.8L E21, and E30 M10 blocks with S14 EVO I and EVO III cranks in them. They are all slightly different with regards to clearance between the rotating assembly and the inside of the block. The fact that yours is a modified 2.0L crank is yet another combination. You never know until you drop it in with the rods attached and try it.

Glad all the deck height and stroke calculations worked out for you. I went through some similar nail biting before I got mine together.

- Steve

[jrcook320]

I'm now in the process of researching the effects of crank end play, thrust bearings, crank walk, as well as the role that connecting rod side play and bearing clearance may have in all of this. I found a few interesting articles:

This article suggests that excessive rod side clearance can contribute to reduced oil retention in the rod bearings, which subsequently unloads the main bearings' oil supply through the process of centrifugal force. While this article focuses on the crank walk issues of the 7 bolt 4g63, there are some good things to consider here about the relationship between bearing clearances (such as why rod bearing clearance is less than the mains).
http://www.jackstransmissions.com/pages/crank-walk

The takeaways:
1) The alignment between the two halves of the thrust bearing have to be perfect or the bearing edge will act like a squeegee and wipe off the oil from the crank thrust surface. Properly seating the thrust bearing will eliminate this problem.

2) The centrifugal force of the rods orbiting the crank can create a suction and pull oil away from the mains, particularly if the oil passages in the crank are too large and/or the rods allow too much oil to flow out of the rod bearings for the oil system to keep up.

Oil starvation of the mains can be caused by the following:
- If the main bearing clearance is tighter than the rod clearance

- Excessive aftermarket rod bearing clearance

- Excessive rod side clearance. Also, wider rod bearings can potentially result in longer bearing life due to more surface area, as well as hold more oil in to prevent loss.

- Enlarging crank oil passages to "improve bearing flow" can be a bad thing, potentially contributing to low main bearing oil pressure.

I'm hoping that tight rod journal clearances will negate the concern about increased rod side clearance. I may also consider bumping up oil pressure with a shim on the relief valve the way Steve did on his build.

And here's a great article on a bearing installation best practices:
http://www.circletrack.com/howto/181...aring_install/

Aside from the usual bearing clearance check, there were a few good notes:
1) it's imperative this complete process takes place in a temperature-controlled environment.

2) Check for proper oil hole alignment, and enlarge the bearing hole if a misalignment exists

3) lightly sand the back faces of the bearings (they suggest 320grit, I'd use 1000 or higher) to remove any burrs or high spots

4) deburr, chamfer, and detail both rod big ends and main bearing caps/journals to ensure no sharp edges effect bearing fitment.

5) Main caps should be seated by tapping into place with a mallet. Seating the cap by torquing the bolts can result in a broken main cap.

6) Check for both main-bearing and rod bearing side clearance to ensure adequate crankshaft radius clearance. Inadequate clearance can lead to bearing radius-ride and premature bearing failure. If present, this problem can be corrected by adding a slight chamfer to the side of the bearing. If I choose to run with my large end play, I think this will be a critical step to ensure that excessive end play won't cause any other bearing interference issues, as well as ensure the quad 4 rods play well with the BMW crank.

[jrcook320]

I consulted a friend of a friend who's a highly skilled engine builder. When asked about my endplay concerns, he laughed and stated the motor wouldn't care if it were .012" as long as the crank throws weren't running in to anything. That's the second machinist that has said to run it. That's good news to me, so it looks like I'm going to keep going with an endplay that is .001" above tolerance.

I've checked for proper crank radius/bearing clearance, and of course the crank walking in to anything isn't a concern. I've also concluded that the larger rod side play I will have shouldn't have any negative effects. My rod clearances are a tight .0015", main clearances are .002". Even if my rod side clearance were stock, this is such a huge gap compared to rod bearing clearance I don't think it could have any effect on rod or main bearing oil pressure.

A few updates:
Prepping the block for paint:


Freeze plugs in:


Several heavy coats of engine primer and engine enamel:










The rotating parts:




Main clearance:


.008" end play:


and finally, one slug in to check block clearance and deck height:

[bmac320i]

I'm so happy to finely see that crank being used. It sat in my shop a few years.

[jjgbmw323]

Nice work Josh!

[shauer]

I agree, looks great! Nice shiny block will add at least 10hp.

Can't wait to see how this runs. Makes me want to do something with my spare m10 block in my garage right now.

Steve

[iferro]

Awesome build! I'm just starting a similar one (minus that awesome crank)

Any progress?

[Dev893]

What was the cost for all the parts? I'm looking to rebuild once I have the money for either a spare drive train or another car

[justinca540i]

Dude awesome E21. I would love to own one someday