m52 crank/ b27 rods/ b25 piston build, ready to start.

[rvaughnp]

Well, i got my crank and hub in. I have classes to teach the next few weekends but i still hope to get this thing moving forward.

Build:
m52 crank (Weights shaved down and balanced) - Done (cut down about.325/8.25mm off weights. It didn''t need that much, but it is what it is.)
head work (three angle, clean up)
Miller chip and MAF combo
272 cam
b27 rods - Done (balanced)
b25 pistons - Done (balanced)
19# injectors (Bought off ebay)


Maybe:
IE rockers
headers

Along with the usual gaskets, oil pump, etc. I put the list in order of expected completion. I will continually edit with (done) when each item is completed.
I will also be keeping track of purchases from the build as to break the build down from the total, once done, to just the items it took to rebuild it as a budget. I originally wanted to stay budget, but as time went on and all the research done; I couldnt just leave it at just a budget. I think they call that "the bug". :( I've got my Bentley, and most my parts. It's just a matter of getting them done and putting them back together.
Wish me luck.

Robert

[Danny]

Buy my plug and play megasquirt to run it.

[rvaughnp]

nope, thanks though. don't want to have to learn a new computer system. Done the research sticking with Miller... for now. I would like to get away from the points and what not. Just not in the budget or time frame. Maybe if i go turbo in a few years.
thanks again.

[rvaughnp]

Took the crank to the machine shop; I should have it back by late next week or the following week.He is going to be grinding the bottom of the crank in an elliptical manner. Not taking the entire bottom off evenly; then balancing it. $350.00.
I saw a couple of V8 cranks that customers used for larger strokers that he had already done this to. Made since to only grind off what was needed to be ground.

I will try to bake and clean the pistons this weekend or the next. Two more weekend classes to teach; then its purchasing bearings and installing the crank and pistons. It's nice to finally get this ball rolling. (Done)

[nando]

wait why are you grinding the crank? less weight?

[SpecM]

^ some say the m52 cranks counterweights don't clear the m20 block or intermediate shaft or something... maybe thats why?

or less weight, thats good too

[nando]

I think it's only S52 cranks, but in any case wouldn't it be easier to turn down the intermediate shaft? I don't think it needs very much.

[rvaughnp]

Not actually sure where the intermediate shaft is in the m20.
The reason for shaving the counter weights is that the bottom portion of the crank hits the skirt of the piston. (think of the counter weight at BDC now run a stright line from 6 to 4 o'clock.)
One thing should be mentioned as to the blocks...

From Jim Rowe...
Who has built hundreds of m20’s.

1)There is no difference in deck height between 2.7 and 2.5 motors, they are both m20 blocks.

2)There are some differences but only in the lower end. In brief… the 2.7 or m20b27 has oil passages to deliver oil to the lower part of the crank bearing. The 2.5 or m20b25 does not have these.

3)The casting is slightly wider in the lower portion of the 2.7/m20b27. He stated he prefers to use this block because there is less material to cut away when installing a large crank and the oil passage.

I did spin the crank without rods and it rotated without a hitch.
Winfred has done this conversion. http://www.r3vlimited.com/board/showthread.php?t=109847

[der affe]

check out my con rod lightening thread. i was able to knock 48 grams of weight per rod with polishing and a little machine work.

[rvaughnp]

Give me a link.

[der affe]

there you go

http://www.r3vlimited.com/board/showthread.php?t=159988

if you want to do it and have any questions, let me know

[rvaughnp]

That's cool and a nice job. I am looking for just a fun " around the town" car for now. Thanks though. I may look at doing some of it. My time is spent between instructing classes, going to classes, work, two teenage daughters and a wife. She gets most my time.

[e30rapidic]

I have almost the exact same setup as you....

M52 crank - ground down big time to clear the piston skirts and the block internals
325e rods
325i pistons with almost all of the skirt cut off
BMP chip
larger AFM
19 pound injectors
4.10 rear end

I really did expect it to be quicker than it was....so don't expect a huge pickup. I have a tuned F150 FX4 that I feel is just as fast! It has 370 HP and weighs 6,000 pounds!

I want an S5X now but think its better that I stick with the 2.8 and just turbo it.

[rvaughnp]

- Did you take pics of the crank?
- How would you compare the power to stock?
- Did you use the 2.5 block and find it wouldn't rotate?

At least i am glad to find someone else that has done this. I have search the internet and only found a few that had. Sorry, you weren't one of them.
Let me know about the above questions, thanks.

[rvaughnp]

Just ordered bearings, rings, and misc to get the pistons in the block; should have the crank back next week. Machinist is a little on the procrastination side.

Just got through cleaning the pistons (tide and water over a hot fire and then soaked overnight) came out really clean. I have a couple wrist pins not fitting right but will take back apart and reclean/check.

Slowly but surely, I hope to have the crank in the block by next weekend and have it spinning. Still have work to do on the head and what not, just trying to squeeze in the time.