Cyllarus

The car: recently purchased 97 with 12x,xxx miles on it, stock motor, running megasquirt.

Future plans: Regular track days (3+ hours seat time) , eventual turbo, eventual Exocet swap

Me: experienced mechanic coming from honda K series world, plenty of bolt on work, but never any engine internal work ( bearings, valves, headwork etc)

The problem: last track day engine spun bearing #1 3 laps into the first session >:(

The question: Rebuild myself? Have shop rebuild? Replace with used engine (97 or 99-00)

Rebuild myself: PROS I will take my time and know its done right. CONS: never done it before, might make noob mistakes and just end up with another blown motor, might end up costing quite a bit
Engine shop rebuild: PROS: fast, will be done right (probably) CONS: expensive (?), to a shop its just another motor and they might not be "just perfect" with it ( i just never trust someone else's work as much as my own)
Replace with junkyard engine (refreshed seals n stuff of course) : PROS : fastest route to getting back on road, probably cheapest option, know bottom end is "at least" factory reliable CONS: another unknown engine with unknown lifetime under race conditions

Would love advice.. not looking to spend 5k right now so please dont suggest a full-out-of control race build.
.. looking for the most reasonable route to a race prepped motor without spending so much that I cant afford track fees.

sixshooter

iTrader: (12)

Have a shop do the short block. Buy the Chinese Ebay forged rods and get the 8.4 or 8.6 CR forged pistons (often Supertech or Wiseco) in the size the machine shop reccomends after they measure the bores for wear.

Crank may be able to be polished and not need to be turned. Order bearings once the shop tells you. Have them remove the oil gallery plug from the back of the block and ensure there's no metal hiding in there.

You can pull the crank and pistons out yourself. Take a rifle cleaning kit and solvent and clean all of the bores in the crank, especially the blind ones. They can hide metal bits and debris.

Replace the oil pump. Many use Boundary Engineering for their billet pumps for track duty because stock ones occasionally explode.

Pull the cams and inspect their bearings for wear and debris. Many times a head will be fine unless lots of metal wear is present. If debris is present you should consider pulling the gallery caps on the back of the head and cleaning the galleries thoroughly with the rifle cleaning kit.

Don't mix cam caps up. Each one goes back in the same place facing the same way.

Same with rod caps and main caps.

Factory rods are weak and stretch when you miss a shift, just FYI.

The shop can reassemble the short block and you can double check behind them or you can reassemble it yourself, which will require some tools and some reading. Pistons have a front and back. Ring compressor needed. Ring gaps are staggered. Torque in stages. Proper use of Plastigauge might be worth reading. Assembly lube is your friend. And more...

DaWaN

I did my first BP engine build this summer.
I had an oil burning BP-4W ('98) motor sitting in the garage.
Machine shop did hone the cylinders and skimmed the head.
Very minimal cost, only around 500$ in total for new bearings, seals, gaskets and piston rings and machine work.
Engine runs like a champ and did not use oil in the 2500 miles I have driven.
I now feel comfortable doing an engine build with expensive components.
I would encourage you to read up, learn and get your hands dirty. I do not regret building my own engine!

Cyllarus

@sixshooter - has a billet oil pump already, and there was verry little metal in the pan, no flakes whatsoever, hoping that i shut it down fast enough after I heard the Knock that I avoided getting too much metal in the oil.

@DaWaN Might lean on you for some noob to noob advice.

Currently looking for a shop to take care of the block / crank and having no luck. What service should I be asking for? Engine rebuild, block honing & conditioning?

DaWaN

I think you need to have clear for yourself what you want to achieve with the engine rebuild. If you want to go turbo in the future I would at least upgrade the rods during the rebuild.
How far to take the rebuild depends on the damage to the block and your budget.
If everything looks alright minus the spun bearing, you could do a very minimal rebuild with only new bearings, seals, rods and piston rings.
Only thing you would need to do is checking/measuring everything and deciding whether the condition of the block is good enough (oil clearances, cylinder bores, valve guides and seats, etc.).
If you feel comfortable to do this job, you can start reading about all these subjects and learn how to check your block.
If you are going to assemble your own block, I think it would be important you would be able to check the machine shop work. If you can check the work, you can also come up with clear instructions for the machine shop.

matrussell122

iTrader: (1)

just find another stock low mile 1.8 and drop it in then save your money and get the Kmiata kit for the long term

sixshooter

iTrader: (12)

If you already have the boundary oil pump then disassemble the oil pressure relief valve in the pump and clean it thoroughly. Look for any marks in its bore.

Do the rods and low compression forged pistons and you won't ever have to go in the motor again.

I would still recommend disassembling, cleaning, and inspecting everything so it goes back together right and lasts.

If the cylinder bores are beautiful you can probably hone it yourself but I would feel better with a machine shop measuring them. You just have to take a look at them and see what you think. You can buy the tools to measure it yourself. You can inspect scratches and see if your thumbnail hangs on them. You can see if it has a ridge that needs to be reamed. It is much more difficult to tell if a bore is oval shaped without good measuring tools but it's not terribly big problem on our engines. It helps that our engines are small.