944obscene

No, I actually didn't know that. I thought it was an interesting read and really gained something from your input. No sarcasm. Just a 5 second response stating my thoughts.

On the other hand. I say the motor can be resurrected. I've seen worse. You think that looks bad? My dad's 1949 F-1 was bad all over before restoration. And the motor? Geez. But the work needed to bring that flathead back around wasn't as much as we thought it would be. Even with the oversized pistons needed due to the bore and hone that was required to clean the cylinder walls. After it was all said and done, the motor rebuild only cost about 8 grand which isn't bad, considering the prices of rebuild parts for flatheads. I mean. Genuine flatheads (not the French or foreign motors).

Yours just needs to be cleaned and machined I bet. But I haven't seen it in person.

patsmx5

iTrader: (16)

Back before the war we used to rebuild them flat heads yes sir. Send em out for rebuild. Come back with knurled pistons to get them them tight again and fresh leather in the bearings. Good for another 40K. And she'd fire right up and get'on down the road.

hustler

iTrader: (6)

I paid $1100 for bore, balance, head rebuild / casting clean-up, resurface, all bearings, a few other little things, and assembly.

bore it or get another block. Considering the price, I will probably never put a junk-yard motor in my cars.

MikeRiv87

iTrader: (12)

Just a quick update. I decided to take a trip to harbor freight and buy one of these bad boys.



Seeing as only one cylinder was really rusted i decided the $15 was worth a shot. Attached it to my drill and maybe did about 3 rotations and moved in an up and down motion to keep the crosshatch on the cylinder walls. Cleans up the cylinder pretty nice, and now the engine can rotate freely. Picked up a headgasket and used my leakdown tester to check and see what i had. The other three cylinder showed about 8% leakage and the "rusty" cylinder showed about 10-12%. I just going to drop it in as is and hope that when i run the engine it cleans up the wall even better and doesn't burn too much oil. What do u guys think?

paul

iTrader: (21)

Just because it's you I am predicting epic fail.

MikeRiv87

iTrader: (12)

I know, I have had some pretty bad luck lately... I'm thinking it's time to make my own. Anyone else have a prediction? I know it will run, how much smoke/power i make is another story.

patsmx5

iTrader: (16)

Epic failure in your very near future. Super accelerated wear leading to massive oil consumption is in your future. Did you "hone" it with the shortblock still assembled?!! Remeber the "epic" thread when the guy put that headgasket repair stuff in his oil?

patsmx5

iTrader: (16)

Seriously this is gonna be a HUGE waste of time and money. Just get the damn thing bored out and get oversize pistons. You're pissing in the wind right now.

MikeRiv87

iTrader: (12)

Really not an option... Guess we will have to wait and see what happens.

patsmx5

iTrader: (16)

What about getting a good used short block from a local pick and pull? I said this earlier and you never commented.

MikeRiv87

iTrader: (12)

I was going to try and find a kia block with the mbsp but i just dont have the time. I cant believe that dumb **** shipped me an engine with no spark plugs. That motor is so clean besides the one cylinder. Even if i can get maybe 10k miles out of it i will be happy. Motor was sold only having 90k.

patsmx5

iTrader: (16)

Are we talking about the same engine? The pics in the first post look terrible. "so clean" is not exactly how I would describe those cylinders. And I'm guessing from your other post you already assembled the engine? If this was a car you were trying to get running long enough to sell it, I could sorta see doing this, though it would be dishonest to the poor sucker that bought it. But you're planning on boosting this engine?

patsmx5

iTrader: (16)

Also, from the first pics that motor had a blown headgasket between cylinders 2&3. You should at least put a straight edge on it and make sure the deck's not warped. Also have to ask yourself what blew the HG. If this was an engine from a stock car it likely overheated which is not good on the pistons and rings. I had a 302 that was severely overheated and blew both HG's. Replaced them. Motor ran, but was very "weak" and would loose oil pressure at idle once it warmed up completely. Tore it down to rebuild it and damn, the pistons were like purple colored scorched on the back sides.

MikeRiv87

iTrader: (12)

ok ok. What short blocks should i be looking for? The 99 short block was of higher compression than the earlier model 1.8L's correct? I would have liked the higher compression for better torque down low during autox.

paul

iTrader: (21)

90-95 8.8:1
95.5-97 9.0:1
99-00 9.5:1
01+ 10.0:1
msm 9.0:1?

MikeRiv87

iTrader: (12)

OK i found a few sephia motors with low mileage for cheap. If i use the 00' head on that block what else would i need to change? I would assume i would have to switch the oil pans because of the fwd to rwd switch. Will the 00 pan clear the MBSP on the sephia block?

patsmx5

iTrader: (16)

95-97 Kia Sephia engines are mazda BP 1.8's. Same engine the 95-97 miata got for the most part. 98+ kia engines are 100% different and nothing is compatible so don't buy one of these.

The short blocks are identical for the most part, but the kia engine has the MBSP. You'll need an 01+ oil pan to put on the kia short block so that it will fit in a miata. Some say you can grind some spots on the oil pan and gain the needed clearance to run a regular oil pan. No experience here but it's been done successfully. I plan to make the stock pan fit if I ever switch in my spare kia engine.

Higher compression is EXTREMELY overrated. Like seriously OMG 4realllz. 8:1 vs 9:1 is at MAX a 4% increase in power. For example at 3K an 8:1 motor has 85 HP. Your talking a maximum gain of 3.4 HP with the higher comp motor assuming perfect tuning. Negligible. Once your in boost low comp has the advantage of running more boost with less heat to make more power reliably.

paul

iTrader: (21)

Try checking www.solomiata.com

He might have that info there.


edit: nevermind, pat had your answer.

MikeRiv87

iTrader: (12)

one quickie... Do i need to switch over the oil pickup tube from the 00' block? So it would be... Switch heads, clearance/swap 00' oil pan, swap over 00' oil pickup. Then i will be back where i was but this time with slightly less compression and the added strength of the MBSP. Not to bad of a trade off i guess. Just a pita. Anything worth saving off the kia head to try and resell to the Miata crowd or is it all junk? I guess i could also sell the 00' crank and pistons to re-coupe a few bucks as well.

patsmx5

iTrader: (16)

The kia engine is front sump IIRC, so yeah you'll definately have to swap the pickup tube. (notice I mispelled definately using an "a" instead of an "i" between the n and the t? I'd sell a kidney to shake off that bad habit)


I will say this: Buy the mazda complete engine gasket set for a 99. It's worth it's weight in gold. Nothing sucks more than "new" **** breaking or failing. And it's actually like 190 for everything including the good MLS HG.

Breakdown for a RELIABLE engine:

Get 95-97 kia engine that's in GOOD condition. Preferably one from an automatic (99% sure auto trans engines have a 6500 rev limiter and hence the engine is like "new" as it has never really been worked hard) Preferably, you will pull the engine yourself and can pick and choose the right engine. Mileage isn't everything, though it's certainly a consideration. Reading the sparkplugs will give you a pretty good idea about the health of the engine. So will pulling the valve cover and inspecting for cleanliness.

Perform compression test and LEAKDOWN (read what I just said again) to verify you are buying a good engine not a worn leaky engine. You've already got a worn leaky one. No need to buy another right?

Make note of leakdown numbers.

Remove head, oil pan, pickup tube, water pump, oil seals, and timing belt covers from kia engine.

Install new (note I said new, not old, not rebuilt, not "I bought this last year it doesn't have much time on it") water pump for a miata.

Clearance oil pan.

Install miata pickup tube

With a good torque wrench, retorque all main and rod bearing bolts to tight end of factory spec

Install oil pan using good gasket sealer stuff.

Install new front and main oil seals.

Check deck of block and surface of head for warpage using a straight edge and a feeler gauge. Odds are the block will be perfect and the head will be within spec if has never been overheated. If the head is warped past
spec, it has to be resurfaced flat again. If it's warped, it's because the engine it was removed from was overheated. Have the head chemically checked for cracks at the machine shop that surfaces it.

Use a 99+ multi layer steel head gasket. Mazda gaskets are good and so are Fel Pro. I'm running a Fel Pro and it's identical to the mazda gasket.

Install head and torque to top end of factory spec.

Install new cam seals.

Install new high quality timing belt and miata timing belt covers. I'd suggest replacing the tensioner and idler pullies while I was in there for peace of mind. I say this cause I cheaped out and didn't and now I have an idler making a bad noise. Should seize and break the belt any day now.

New radiator hoses w/ real hose clamps and new belts NOT overtightened are a must too.

You do all of that and you'll have done something. Skimp anywhere, and you're compromising reliability.