Doppelgänger

iTrader: (12)

Well...IT'S ALIVE!!!

Got to drive it home from my friend's shop. After doing the pre-start checks, I primed the engine and it fired right up. Everything was great except for 2 things-

1)I'm still smelling gear oil from the transmission. I put 2qts in via the shifter turret. Nothing is leaking.

2) The driver's side engine mount was replaced with a new OEM unti. The pass side is still a MazdaComp unit. I didn't think about it right away, but the MC mount sits the engine in a slightly different position. So the engine has like a 2* lean to it right now which is putting the turbo compressor about 1/8" away from the frame rail...and it bumps when the clutch shudders or hard bumps/turns. At least this is what I suspect is the deep "clunk" noise I hear when the clutch shudders or over hard hard bumps, or under heave lateral loads.

So other than those two issues, everything is nice. I replaced the rubber bushing ON the shift lever and combine that with the new TOB and clutch fork pivot bolt and shifting is wholyfuckingbeautifulawesomeperfect. Shifting is so smooth now that the spring action of coming out of gear almost put it's into the next gear without even pushing it. I have not been into boost yet though :( I'll give it until a couple of hundred miles before I do so, and I'll jsut be at WG pressure at first before returning to 12psi.

JasonC SBB

Coolant holes different, oil holes same.

JasonC SBB

If you don't know WHY the 1st engine blew, how do you stop it happening to the new one?

chpmnsws6

iTrader: (12)

I'd be Leary of the turbo hitting the frame rail. It might put undue stress on the manifold, giving you even more issues then before.

Doppelgänger

iTrader: (12)

Autopsy will be under way soon. Give nthat the engine was boosted for as long as it was, I highly doubt there will be any problems anytime soon. But soon as I get the exact cause, I'll post it up.

Oh trust me I am. I know I need to get the other MC engine mount asap. So until I do, it's easy driving everywhere I go. Hell, I might even go pick one up after work today and see if I can get it in tonight or tomorrow.

Doppelgänger

iTrader: (12)

.....and that engine lasted 3.5 years/70k miles lol. Shitty west coast gas + boosts = detonation = rod knock.

curly

iTrader: (25)

I've really never heard anything bad about our gas. I've heard bad things about California gas...but it's advertised as lower 91 octane vs. our 93. You might just be pushing your luck with 10:1 compression, 14 psi, and an aggressive spark map. It lasted only 32k less than your "Georgia" engine, and only 10k less boosted miles. Seems like it did just fine for your modifications.

Doppelgänger

iTrader: (12)

While kinda true, there are differences:

-I never had a problem with detonation/misfire on GA gas, but it was also very awesome 93.
-1st failure is still a mystery. Engine didnt look bad at all upon tear down.
-I'm now running Jeremy's map and boost was turned down to 10psi months ago.

In all honesty, I'd think 70k of 12+psi on a stock motor isn't all that bad. I do drive the car hard and the $$$ per mile of entertainment is actually pretty damn cheap lol

curly

iTrader: (25)

Considering what, $2k for parts and rebuild? Maybe 3? That's 3-4 cents per mile. Very worth it

See my post on CR, my hoist is waiting to go home with Martin!

Doppelgänger

iTrader: (12)

Got a price on stock 4W pistons- $58/ea and $115 for a ring set. NLM got back to me with good prices on rods/bearings/ARP head studs and a pretty blue t-belt. Now I just need to find a good place for a gasket/seal kit...been reading MT for suggestions. I am contemplating having the pistons given a ceramic treatment.

Tentative parts list:
Manley rods
Stock 4W pistons
OE rings
ACL race bearing kit
ARP head studs
Gates Racing blue t-belt
OE t-belt pulleys
New WP
All new OE seals/gaskets

On the fence about:
New OP
Ceramic coating for pistons
SS 1-piece clutch line
Valve seals (included with Rosenthal gasket kit)

Right now for all of that I'm looking at $1362 for all of the parts.


Looking at the TSE and 949Racing dampers or a brand new OE unit (depending on price). Though I feel keeping stock pistons and not really going for over 300rwhp might negate the need for an upgraded one...though mine now has 70k boosted miles on it.

Also, I am not sure if I need stock size pistons (84mm?) or if I need oversize (84.5mm?) and same with the bearings..."std" or upsize one. If rebuilding, will I have to bore the cylinder walls or just re-hone? After pulling the plugs and looking down on the piston, I see no evidence of anything having been thrown around, so I'd tend to think there shouldn't be any damage to the cylinder walls. If the knock is at the rod/crank/bearing, will I need the larger bearings as the crank will need machining? Am I crazy for thinking about having the crank go through some weight-reducing machining?

Am I crazy for thinking about having the crank go through some weight-reducing machining?

Should I have my injectors sent out for cleaning/servicing?

What are the standard procedures a machine shop/engine builder will perform on a rebuild? What services are generally extra? Should I specify any particular work?

I don't really want to add cost with head-work/parts upgrades, but should I really do any particulars? Valve seals at the least?

curly

iTrader: (25)

Cermic coating would probably be worth it for your OE pistons. SS line is definitely worth it. If you're referring to the full length master to slave one, I'd probably say it's nice but over kill. Something like TSE's though is very nice to have when working in that area. See below for head suggestions. And I've heard way too many horror stories about upgraded OPs. Pressure release valves seizing, improperly machined housings, etc. I wouldn't upgrade at your power level. Make sure you release valve spring is within tolerances and leave it alone. Others will most likely strong disagree with me.

You're probably ok with your stock pulley, although if you're going to buy a new one, just buy the 949 unit.

You most likely didn't damage the cylinder walls. Even the exploded piston engine I recently built didn't damage the walls past what a hone took care of. Any honing done still uses stock diameter pistons. If you're buying new, bore it out for power, definitely. Are those 84.5 OEM pistons? A bore isn't super expensive and probably worth it.

The crank is most likely ok as well. It'll need to be checked for damage and oil clearances.

Yes. Don't waste your money and sacrifice reliability.

Definitely the seals, and have them check valve seats as well, along with a surfacing and cleaning. This should run you about $150 IIRC. Wouldn't be a bad idea to check if there are any bent valves, and have them do a 3 angle valve job as well. Valves are super important in making strong compression numbers and are often ignored.

Doppelgänger

iTrader: (12)

Thanks Josh. The OP idea was just to get a new OE OP, not an upgraded unit. I remember some of those horror stories.

My questions concerning the piston size is cost. Will it be that much more to bore out for oversize? I can get either stock or over-sized for the same price. Should I go with over-size? Any idea on the new cc displacement? I'm reading conflicting information on the stock size being either 83.5mm or 84mm....

Doppelgänger

iTrader: (12)

Finally about to start ordering parts, fun. Looked up the "straight shot" clutch line...seems stupid not to do for $50.

I'll likely order std. bearings and the .025" ones as well...and just send back what I don't use. Does Mazda offer the mega-gasket/seal kit as a single part number like what Rosenthal sells? I have a feelin with my connections I could get that for ~$50 cheaper...if I knew every part number included in their "kit". GASKET SET,ENGINE (8DN5-10-271) - $293.30 - 8DN510271 .....can't tell if that's a "true" Mazda part number or one of theirs.

What else to do without spending another $1000....

curly

iTrader: (25)

Its .0025, big difference

Doppelgänger

iTrader: (12)

Yeah....sorry!