Another 2056 rebuild thread, It's Alive! Options

[nditiz1]

So I decided to start this reBuild thread to keep track of everything as well elicit help and possible things to watch out for. I haven't owned my Porsche a year and I have already killed the motor and taken it apart (IMG:style_emoticons/default/biggrin.gif). If you are unfamiliar I was in the process of upgrading my distributor and out of sheer luck dropped a valve on #2 which I eventually found out it started its life as #3. The 2056 was rebuilt by the PO before the PO I bought it from. With the help from you all and some nice vids/write ups I confidentially dropped the motor (much easier with dual carbs). I purchased a 4 bar 914 stand from a place that manufactures all types of engine stand mounts. I broke down the motor to the short block where I found no other damage except the broken valve. Piston #2 was slightly injured, but I felt as new P&C was the best approach. Mark (McMark) has been a huge help through the process, thanks Mark! Since I didn't build this motor nor have any specs really on what was inside I decided to check it was a 2056. The bore measure 96, the stroke measure 71. I was told it has a mild cam. No markings could be found on the front of the cam gear. I did some prelim measurements of lift and found it is not stock and that the intake and exhaust have different lifts.

With the motor down to the short block it was time to buy some parts. I bought new P&C's from AA pistons. They are the 96mm flat top ones with a valve relief. I ordered new 2.0 heads (AA piston HAM heads) from Len. I bought the type4store spacer kit, thorsten 10mm swivel feet adjusters, and had everything machined by a guy on the samba that lives in CA.

I replaced the RMS with a Sabo one and checked the endplay to be in spec. The parts needed for this was the Sabo RMS, felt washer, flywheel bearing, inner flywheel seal, and a 5 hole crush washer. I wasted one crush washer as I did not put any lubricant on the flywheel seal nor the RMS. Following the pelican article it states to make the flywheel bearing flush, but this leaves little to no room for the felt washer and actually made the washer deflect slightly when torqued. It is now set to the 3mm protrusion which is the thickness of the felt washer. The flywheel is still currently off. I asked about my clutch and pressure plate and they look new so I won't be replacing them. The engine seal rebuild kit I bought is the Victor Reinz one. It only comes with the crush washer so be sure you get the other parts if you do this job. Back to the rebuild kit it would be really nice if it came with a guide for what every seal/gasket was and where they fit.



The rebuild:

Replaced both the taco plate, oil filter, and oil plate.
Test fit the P&C.

I removed all 4 pistons from their cylinders to just check the rings. They all looked good to me, but with nothing to really compare them I'm really just guessing. I did not check the ring gap. Not sure what it is supposed to be. I rigged a setup with a dial gauge, type 1 deck height plate, 2 aluminum bars, and a micrometer. I used the dial gauge to get the exact top of the piston stroke. I checked through several revolutions. Before doing this I removed the distributor drive gear as Mark (914sixer) showed if yours is not 100% in the correct position you can torch the copper gear on the crank. Once I had achieved the top of the stroke I micro'd the depth and subtracted from the thickness of the deck height plate. I came up with 1.4mm for all 4 pistons. Unfortunately, with the cc of the heads and the valve relief it was putting me at a 8.1 C/R. This is leaving power on the table and I know with the valve relief in the pistons I can get a pretty shallow DH. I decided to take the jugs to a machine shop to have them mill .5mm (originally .4mm) off the bottom of the step. I will be running no gasket at the top nor the bottom of the jug. With a .9mm DH it will put me right at 8.5 C/R as the heads are 60cc and the relief is 2cc. This motor had been running at 8.1 (possibly, don't know the cc of the stock heads) which is probably why it didn't feel as powerful as I thought it should and as others commented on my old post the heads were leaking between them and the top of the cylinder.

So that is where everything stands right now. I hope to get the jugs back later this week as well as the blocks, rockers, and adjusters. Mark (914sixer), Brent (bbrock) and I are building similar motors.

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[nditiz1]

Got one side of the engine bolted up with the new head. It looks great! Checked the gap between the bottom of the head and top of the cylinder fin and they don't touch. There looks to be the slightest gap as well. So this should be good and no leaks should result as the jugs will be pressed up against the inside of the head.

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I started on the painful task of valve geometry. Read through several posts as well as Jakes nice write up. So I am using 2 aluminum type 4 pushrods that have been modified by the CA bug guy that did the narrowing of the rockers. I setup my dial gauge to be in line with the valve as though it had perfect (to the best of my ability) angles. The biggest unfortunate thing is I do not have a cam card so I don't know what the numbers should be. I took a micrometer to the lifter and measured the highest lift vs the opposite side of the cam lobe to come up with 8mm or .315 for the exhaust. .315 X 1.3 (rocker ratio) gives me .409 of total lift. Also, I have read through some of the posts about rockers being different ratios from the factory and for simplicity have decided to use 1.3:1 for everything. Bolted the rockers on and began the trials of measuring out to achieve full lift. Here is where I ran into my first hurdle. I can't seem to get close enough to my supposed highest lift without elongating the pushrod. After several attempts with the swivel foot and elongating the adjustable pushrod I got to .403. Since I didn't have anymore room to back out the swivel anymore I decided to check with the stock adjuster. I put that in with the adjustable pushrod and after starting from stock I got .409 after a few minor turns out. I think I need to buy one of those viernze micrometer that I have read about to accurately measure if the pushrod is in fact longer. If I put in the stock pushrod I cannot achieve the higher lift number with either the swivel nor the stock adjuster. Does this sound normal, to be increasing the pushrod length to get to the correct Total cam lift? I'm going to keep working at it.