M42 rebuild and upgrade help

[Massimo]

UPDATE 14/19/10

I have posted this on R3V want optinins from you guys as well.

As the title states I am thinking of rebuilding the M42.

Reason: Well over the weekend while I was looking inside her, I noticed a water leek from an odd spot (on the air conditioner compressor). Anyways upon further inspection it seems to be coming from the head gasket . It’s a very small leek, but one none the less.

So if I am going to replace the head gasket I might as well do a performance rebuild.

Experience: Well non this will be my first ever engine rebuild I am confident, in my skills and hope I have read enough to do a good job. This is also part of the reason I am posting here. I have devised a list of parts I need and the machine work I will get done. I know what the prices are for the parts and was wondering if anyone could give estimates on the machine work required that I have listed.

Goals: Well I would like keep the price under $5000 and hopefully achieve 180hp without any real bottom end modifications beside 360Degree Thrust Bearings and oversized pistons, focusing more on the head.

Anyways here is the list

Metric Mechanic
-Rod Bearings $60
-Main Bearing 360Degree Thrust $120

Total From Metric Mechanic = $180

Vac Motorsport
-Titanium Valve Retainers $289.95
-Hardened Valve Locks $71.20
-1mm Over Sized Stainless Steel Valves $479.95
-Duel High Performance Valve Springs $447.95
-Vac 269/269 Cams $949.95
-ARP Main Stud Kit $149.95

Total Option 1 From Vac Motorsport = $2334.95

Possable Option 2
-Stage 2 Cylinder Head $1399.95
-Vac 269/269 Cams $949.95
-ARP Main Stud Kit $149.95

Total Option 2 From Vac Motorsport = $2499.95

Pelican Parts
-Head Gasket Set $106.75
-Hydraulic Lifters $276
-Chain Tensioner $39.75
-Timing Chain $56.25
-E28 Motor Mounts $44
-Bottom End Gasket Set $65.50
-Oil Pressure Relief Valve $10.75
-Cam Sprocket x2 $108.00
-Crank Shaft Sprocket $67.25
-Deflection Wheel Sprocket $145.00

Total From Pelican Parts = $909.35

Bav Auto
-Oversized Pistons $439.95

Total From Bav Auto = $439.95

Total Option 1 Cost of Parts = $3864.25

Total Option 1 Cost of Parts AUD = $4293.61

Total Option 2 Cost of Parts = $4029.25

Total Option 2 Cost of Parts AUD = $4476.95


So this dose not leave me with much room for machine work so I am just going to list the things I want done and if anyone can put an estimate to the cost that would be good. Then I can review my parts and see where I could save a bit.

Block
-Crank Shaft Alignment Honing
-Decking Surface
-Hone Cylinders

Head
-Deck Surface
-Increase port and valve seal size to suit new valves

Crank
-Probable fix spun main bearing journal
-Chrome journals

There will also be inspection for cracks and repairs but that is an unforeseen problem which I can not list and will just have to see what happens there.

So that is what I have come up with so far. The car has done 190,000km so I am hope there will not be any major problems but you never know.

As you may have already noticed I have not really done much with the timing components, when I last looking at the cam gears and chain it looked in very good condition, so I am hoping that the guides will be in good condition. But if there any evidence of problems then they will be replaced.

I would like peoples comments and any help with what I have listed, also an estimate on the cost of the machine work would be a great help.

Cheers Massimo

PS I should add i am going to try my hand at replicating the Metric Mechanic Pulse Chamber.

[nicknikolovski]

Do not change the timing chain without new cam and crank sprockets. General rule: chains and sprockets get changed together.

So add these to your list:
- Cam Sprockets
- Crank Sprocket
- Idler Sprocket (this has a bearing - if it seizes it's goodbye engine)
- Delete the head gasket as it comes in the head gasket set. Unless you are getting a thicker head gasket for some sort of forced induction later on.

Head bolts: $16.95 each? For the total price, VAC Motorsport should have ARP head studs - alot stronger. Once again it depends weather you want to go down the road of forced induction later on. Also not sure weather the hydraulic valve lifters will hold up with all the performance valvetrain gear (not 100% with this though)

Also I would get a new oil pressure relief valve and oil pump gear set. (You want really got oil supply - you may like to test the oil pressure first though)

[B318M42W]

switch to E28 engine mounts and save some $
+1 on oil and chain stuff.

when getting the block decked, you will need to include you upper timing cover.

[Massimo]

Cheers guys added your input. I also Added Vac Stage 2 Head depending on the shipping cost it could be cheaper as they also inclued most of the machine work in the cost.

[BMWGM42]

personally, i'd just get an MM motor

[M42_Jester]

+1 on the MM motor...
may be a bit most expensive, but the MM 2100FI engine is a beast... xD 205hp!!!

[ubergolf97]

I know it's only a $15 difference, but VAC's ARP main studs for the m42 are $164.95.  Just so you're not caught off guard later on.

I just dropped an m42 block and crank off at the machine shop to be magnafluxed.  I'm hoping they will be good for the rebuild I'm planning.

I hope this isn't really thread jacking, but I wanted to ask about this reply because it's something that hadn't crossed my mind:

when getting the block decked, you will need to include you upper timing cover.

Do you mean include the lower timing cover when getting the block decked?  And if I have to deck the head, I'm assuming i would have to include the upper timing cover?

Good luck with the rebuild!