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M20 Triple weber build x2

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Thanks!  Its crazy to think how long it gets drawn out sometime.  Good luck with yours.



2002 Headlight bucket restoration.


This was pretty straightforward but another project done! Thank you to Jim Gerock for his photos of this and thank you to Tom Jones for the z-beam replica information.



Flathead screw driver

Philips screw driver


10mm wrench/or socket



This was a pretty relaxing project compared to some of the others. Started by removing the headlight buckets from the 2002. Be carefull, I managed to bugger up one of the studs and ended up drilling it out and welding in a new proper-length piece.






Once out, simply dissassemble the buckets. There are the....

1)mounting brackets

2)headlight buckets

3)trim rings (I guess this is an early car thing)

4)headlight retainer rings


Rowan was very helpful.




Once dissembled I stopped by Ronin Autowerks the following morning and borrowed their blasting cabinet.




Then I slipped the parts into the last plating batch (yellow zinc). It would be pretty easy to just paint these if one wanted.


Everything back from plating (along with bringing the chrome trim rings back to life).




Started by a attaching the trim ring and the retainer ring. Note the alignment dimple. I did not have the ring aligned with the dimple the first time and managed to over-tighten the assembly which subsequently cracked the brand new headlight lens! Lesson learned. Should note I picked up these really neat cibie z-beam replica lights. They were domed and even had a nifty driving light.








Screwed the headlight bucket together with the retainer ring. Then placed the assembly back into the mounting bracket and threaded in the new adjustment screws. Also found a nice replacement tension spring and popped it in place.




All done!



Note that the driving light will need more room. I will need to dremel/grind the bucket a bit.



Edited by AceAndrew
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Seats.   This project began with figuring out which seats I wanted to use. The Scheel bucket seats found in the E9 CSL have always been my favorite. They offered great lateral support (compa

Well, haha, we'll see.  I'm just going to enjoy the bajeebus out of it.   Since the car was taken to the paint shop, a lot has happened.    I interviewed at least four paint shops

Final Fab Day 12.1.18   This past Saturday I rolled the chassis closer to the welder and the last of the fabrication was finished. Namely, bolts were welded into the floor.  They will act a

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Block and pistons at the machinists
setting ring gaps
Also on the rods, I ended up selling my set of H-beams to a customer when we ran low.  As a result I had a stashed set of NOS S52 rods as backup.  The rods, along with ARP rod bolts and ARP main cap bolts, made their way over to the machine shop.
Love the tools this guy has, it's like a candy store..
I'm still on schedule to have the engine done by the time our open house roles around next month.


There are two different 84mm cranks that BMW made which will work in the M20.




The first is crank #1748751, as most know it came in the E36 328i, and E34 528i cars.

The second is crank #1432277, this came in E46 323i and E39 528i's.


The second blue-hued (277) crank is a couple pounds heavier but is a very nice crank. I opted for it.


The following clearance work needed to be done to the block in order to fit the crank (the block was from an E34 525i). The specific areas were around the oil return and the bottom of the bores.


Oil Return








Bore Bottom




Oil Pump Auxiliary Shaft (around the casting on the first saddle base). Note this picture was taken after the crank was put in. There was plenty of room between the shaft itself and the crank counterweights.





Hardware lined out.




Measuring thrust.




Back on the engine stand!




Started to slap stuff on the outside. Love torquing that crank nut.





Crank-nut torquing procedure (Yes I know for some that this is as simple as making chocolate chip cookies from a Pillsbury roll, for others [like some of my tech calls] it's witchcraft). This is for the later among us. If these instructions are not sufficient you should really put down your tools and take your engine to a shop before you brake something.


Most torque wrenches don't go up to 302ft/lb. So we use the following equation.


(Weight x Distance = Torque), therefore (Distance = Torque/Weight).


This tells me if I input the desired torque setting and my body weight we will get the distance up the breaker bar that I need to apply my body weight. So once I find that spot on the breaker bar, turn until I need to use my complete weight on the bar (my feet off the ground) and the crank no longer turns then bob's-your-uncle.


In my case 302ft/lb. Divided by #160 = 1.8875ft.


Convert .8875 feet into inches: .8875 x 12 = 10.65inches


So I needed to place my weight 1ft.10.65in. up the breaker bar.


Breaker Bar




To stop the crank from spinning I just wedged a hunk of aluminum between a counterweight and the block. For the cranks sake use a material softer than steel. Wood would work if you made sure to clean fastidiously afterwards.






Piston to valve clearance (Again, I know to some this is as basic as making a Hungarian Pancake. To others its like learning how to gleek).


Things that can potentiall affect clearance, block/head decking, cam lift/duration, piston pop-up, piston valve pocket, valve diameter, valve, lash, and valve seat depth.


I know I'm preaching here but whenever you are building a new performance engine you need to be checking piston to valve clearance. The importance is exacerbated by the fact our beloved M20 engines are non-interference. I can personally remember several instances where the clearance was not checked on a new engine (they just “assumed” it to be ok) which resulted in the destruction of a new engine. Strangely, that bit never made it onto any build thread. Moral; if you ain't sure, get it checked before you turn it on (apparently a good life lesson in general).


Parts needed

-Modeling Clay

-Decent measuring calipers (at a minimum)

-Extra set of NEW head bolts (not used [unless ARP studs])

-Your old headgasket

-All the normal tools needed for a head job


To check the clearance you start by spraying a piston top with WD40 and press some modeling clay on top of the piston's valve cutouts.


Making sure the cylinder head and the block are both at TDC place the head on the block. Then torque-down the head as you would on a new engine (as per the Bentley Manual). Adjust the valve lash on the rockers that line up with the test bore.


Install the water pump/tensioner/cam pulley/timing belt/etc. (as per the Bentley Manual).




Once everything related to the belt and head is mocked up, go ahead and turn the engine over 2-3 times.


Remove the belt and head.


Now rotate the crank so the test piston is sitting at the top of its bore. You should be able to clearly see where the valves left indents in the clay.


Every piston will have a specified amount clearance (if you can't find it, find it.). In my case the new IE/MahlsMS pistons required a recommended minimum of .1” depth and .05” radial. The cylinder head had a light skim and I was using the 284/272 IE NewBillet camshaft.


Slice the clay along the midline and measure using the calipers.






This piston/cam combo measured out to have a depth of .15” and a radial of .06”-.07” on the intake valve (exhaust side had oodles of room). So we are good! This also tells me all else being similar there would be adequate clearance if I wanted to run a 288° cam. It also tells me that I would NOT be safe running oversized valves.


And there we go! Now back to finish the reassembly!

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Finally got an update!

     Handling the transmission part of this car evolved into a pretty neat experience.  I was talking to Rob Inhout last year about the project and he offered to take a Saturday to teach me how to rebuild and do the necessary work on the trans.  Needless to say I was stoked.
      Rob is one of the most humble and experienced people I’ve met within the 2002 community.  There’s a decent chance you haven’t heard his name (or maybe heard it in passing) as he does not seek to promote himself publicly.  He doesn’t typically deal with the public at all, outside of a few ebay listings, rather he deals with the multitude of great shops catering to vintage bimmers down here in SoCal. 
      Rob’s backstory is unique.  He worked for JPL/NASA on both the Mars Rover and Hubble projects as an engineer.  When he retired early he started racing vintage bimmers and ended up buying/owning 2002ad (and it’s neighboring Alfa wrecking yard) for a time in the late eighties.  Now days he does transmission/differential/etc work out of his shop when he’s not skiing, backpacking, or tinkering (there was a half disassembled Prius battery pack on a workbench when I was there).  
      So on the scheduled Saturday I loaded up the transmission and set out to his shop.  The one thing I immediately noticed was the copious amount of 2002’s on the premise. And before anyone whines“look at all those cars just sitting there”, remember each of these cars were saved from the crusher.  Just by sitting there these cars got an unintended lease on life.
Under all that stuff?  A nice little 2002 vert.
A unique way to remember projects … just put them in the way.
      As stated in previous posts, the work being done to this particular Getrag 245 transmission consisted of swapping the bell-housing sections from the M10-compatible piece to the M20 compatible piece (e21 323i), replacing all 5 syncros, and changing out whatever bearings needed changing! 
M20 w/245
-no tunnel fabrication (just some hammer work)
-mechanical speedo (no aftermarket speedometer)
-10lbs lighter
-Difficult to find 
-can be spendy
M20 w/260
-more plentiful
-fabricate tunnel
-electronic speedo
-bit heavier
….. and for giggles, close ratio NK tranny?  This would have been in something like a TISA.
       The first step was to remove the input shaft shroud and split open the case.  You do need to have a special tool to do this (or make one as Rob has done here).
Here’s the split trans you can see a couple of the synchro/gear/dogring assemblies.
Since we were doing the whole nine on this trans the rear cover and midsection needed to be split as well with a separate tool.
       From here on out, things won’t necessarily be in order BUT I wanted to cover some neat bits.  First he’s a shot of the midsection backside.  The spring is for the shifter detents and the gear on the right is the speedo gear!  
It reads off of this this piece on the main shaft.
        Here is an example of the synchro and it’s position on the gear.  The synchro is coated with a wearable-material much the same as the coated disks inside your clutch-type E21 limited slip diff.  As the synchro wears it rides further up this taper and butting up against the gear and not allowing for gear engagement by the dog-ring (the spacing between the synchro and gear should be around .010.  This comes in handy when doing a quick visual check through the fill hole with a flashlight.  If you see a bit of a gap, you’re pretty good)
We wanted to disassemble EVERYTHING so that meant using a press to remove the main shaft from the center housing.
everything wash thoroughly cleaned. and laid out for reassembly.
      One of the changes made was incorporating the stronger front mainshaftbearing.  This meant machining the housing a little along with machining the shaft itself.  
Everything going back together.
Rob himself!
We had to attached and then remove the bellhousing section a couple times to make sure everything was kosher.
One interesting note was my particular M20 housing was not initially tapped for the back-up light switch.
With the trans double checked and largely back together it was brought back to the IE shop and gave the outside of the trans a good cleanup.
Shop cat keeping an eye on things.
Now with the trans done all the major mechanical components are rebuilt and ready!

And thanks for Mike for the awesome photography!




Edited by AceAndrew
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So it's been a while since I've updated this but progress has been happening. 

First off, Mikey made that awesome roof rack for the car.  Cannot thank him enough!




Got the engine in and roughly mocked up for the first time.   Dry M20B29 sans headers weighed in at 297 pounds.


Radiator fit solution: 
I will be using the shortened E30 aluminum radiator with a twist. 


Rather than have a general difficulty of the front being so tight I went with a "strategic" compromise.  I cut the front panel to allow easy access to the radiator which has been tilted forward.  The panel will be held in place via some tabs/bolts/welded nuts.  It should look fairly stock and still offer plenty of working room when removed.

Panel in place over the radiator.


Panel removed when accessing the radiator.


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This makes me want to go the m20 route so bad. I'm torn between this swap and boosting my m10. It seems like anyone who is hesitant to do it is because the m20 is an interference engine with a belt. God, I'd hate to build a gorgeous one like this and then have a belt snap and bend the valves. I noticed that you're using the stronger belt I.E. sells; at least it's lighter than a chain. Is the m10 interference too? I can't find that info anywhere, not that it really matters because if you break a chain it was time for a major overhaul anyway. Could you make the m20 non-interference by using a shorter rod? I know that would lower the compression, but would a turbo or blower be able to compensate for the power loss I wonder?


Also why did you stroke to 2.9 instead of 3.0 or 3.2?

Edited by SnowDriftin3
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Hey, whatever you choose …. own the crap out of it. Doing any swap or turbo should be primarily for fun, don't loose sight of that and you'll be fine.


1) The timing belt snapping of it's own accord is an internet fallacy. Not to say it doesn't happen frequently, but it only happens when kids buy e30's and don't stick to proper service intervals/maintenance. I have NEVER seen a belt snap within the service interval unless something else was at fault. This is going off of seven-ish years now and hundreds of belt kits. I also like the historical tie-in as well. BMW bought Glas primarily for their timing belt technology which eventually manifested itself into the M20.


2) You can make a piston for the M20 that is non-interference, the trick is to have really really deep valve pockets. Unfortunately you end up with an extremely thick piston crown, thin ring package, and a non-offset dish. That's a lot of compromises needlessly introduced when there's no problems with a properly maintained M20 in the first place.


3) I chose the 2.9L stroker because in short it allows for the longest engine life and the least amount of performance sacrifices, especially with those IE/MahleMS pistons. You can have a healthy ring package and not have the wrist pin bore impede on the lower oil control ring (which is what happens on the larger stroke pistons). The M52 crank also happens to be lighter than the stock M20 crank (which along with lighter rods and a lightened flywheel turns the M20 into a rather zippy engine).


Hope that helps!

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Continued to tear apart the interior, had some help from my boys!

I was a little uncomfortable on doing the nose swap myself so the car was sent over to Erik's (coupeking) for the job.  Erik called the next day and said the nose could actually be saved!  This is great news considering is was the original nose and was perfect until I banged it up.  So Erik and Sergio are fixing the nose and simultaneously cutting out some rust around the front fenders.
Headed off...
Here's a fun touch for the car...
Most r3v/02faq guys will probably know about the 02 Diana's ..... when you boil it down they were simply hot rodded 2002's (especially since at least one was M30 and the others were otherwise upgraded)
Since the idea of a number   six-cylinder 02 hot rod sounded appealing. I wanted to tap into that vibe with a proper "diana" rear badge for my car.
Ian was advertising custom badges in the r3v classifieds, I shot him an email with several reference photos..... and well.... he rocked it.
Ian drawing it up....
3D printed
Using the 3d print to make the mold.
Cast aluminum!
Ian did a second badge for me "just in case" and had both powdercoated.  Cannot thank him enough for doing this project.  If anyone (who doesn't have an instant gratification complex or who needs their hand held at every step) is looking to spend some money for a handmade custom badge then Ian does awesome work.
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  • 3 weeks later...
Made some headway on the body! 



    Car got back last week, poor tow truck driver spent 3 HOURS driving 34 miles from Longbeach up to Duarte through rush hour traffic (woohoo LA). 




      Looked over the car this morning, everything looked spot on. Erik's guy repaired the rust at the bottom of the nose, straightened the lower lip, and repaired the little bit of rust at both front rockers. Going to get the rest stripped for blasting.  Splurged on a Martin hammer & dolly set so I can tackle the remaining dents before handing everything over to Ayed at Kings Autobody.


Nose before:



Nose after!  Don't mind the crooked hood.



    Finally got my holy-grail of a steering wheel!  Nardi Anni60 (plus horn button) as used on the Ferrari 250 Lusso/GTE/365/etc. 




 It took some time but I also sourced the matching ash tray out of Germany.  Both the wheel and ash tray have the same engraving pattern.  Traditionally it had a little Cavallo and Pininfarina badge on it, so in that spirit I stuck this neat little BMWCCA badge in its place. 



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I promise I've been working on the car!  Have a couple progress points that are nearly reached.   


Interior is almost accounted for, will put up some pictures in the next week or so.  Trim and bumper rehab has started.  Car is almost fully stripped.  Holes are welded shut but the glass still needs to come out.  


Started at my new job last Monday.  Commute has gone from an hour and a half down one way to fifteen minutes.  View from my desk is nice.



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