Minimum to replace rods
 

So, I'm wanting to go in and replace rods in my engine.

I don't need pistons, oil pump, or anything else as all I'm looking for is ~250rwtq max. I'm just looking for a /very reliable/ 250rwtq, nothing more.

What's the bare (sensible) minimum? Rods and bearings? I don't think honing is required if the same pistons go into the same bores.

rods, rod bearings, headgasket, IM/EX gaskets, rear seal as a minimum.

clutch bearings as a precaution as a "while your in there" and maybe a re-ring depending on mileage

Smacking myself for forgetting the head gasket on my list, thank you Neilv. Although I have a set of FM clutch bearings in there with < 5k, so I think I'm good there. Engine has ~100k on it, so I'm fairly okay with the rings considering compression is good.

Thrust washers worth replacing?

I think it would be insanely silly not to clean up pistons, lightly hone walls, and replace rings.

Are you going to run stock oil pump? May want to add BE pump to the list too... That and what 18psi said

^What he says^

Is there anything wrong with the engine? Why not have a reliable 230 rwtq and when you're ready build the whole thing?

Rings have 100k on them. If I am still running this Miata 25k-50k from now, I'm going to be doing a fully forged rebuild on it w/a ported and cammed VVT head. I don't view it as a particular necessity to replace the rings immediately as a result.

If I still have the same Miata a few years down the road, I'll just be doing a fully forged internals build as I mentioned above.

For personal peace of mind and experience pulling the sucker apart - I don't want to have a big dollar, no expense spared build be the first time I have an engine apart.

rings are like 80-90 bux. it would take about 10 minutes to do it. with 100k on the originals I bet a good chunk of that "good compression" is due to gunk build up.

whatever, its your car lol

Where can I get rings for 80-90?

Cheapest I've found is closer to 150 - at that price, I am probably going to jump on them.

(Edit) Well, I guess I could get no-name autobone rings for $125ish + tax....Is where I am just unusually expensive or what?

(Edit^2) Holy shit. Online sets of piston rings are half the cost of suppliers locally. Thanks 18psi, I'll probably be picking rings up.

rockauto.com

"premium" chrom-moly ones were like 100 bux last time I got em.

the car still runs like a champ

Yeah. I'm going to be ordering a ton of stuff from Rockauto 18psi, I am having trouble believing they are /that/ much cheaper than local suppliers, but they are.

One part in particular is a third of the price locally!

RockAuto has rings for stock pistons at $35 for a set I believe. I know for my supertechs a set of replacement rings were about $100 from TSE. If you are trying to go cheap I would say pick up an engine rebuild on ebay here. Then pick up ebay rods for like $250 and then you are at about $500 in rebuild parts cost.

Graphite head gasket is fail@link :(.

I like your idea a lot, Shoes, and wish I would have done it from the start. Already got a timing kit to go on though.

So, what's the difference between stock pistons and these steel topped pistons:

94 97 Mazda Miata MX5 1 8L DOHC BP Engine re Ring Kit | eBay

? 'Cause that is kind of tempting to pick up - oversize pistons, MLS everything gasket-wise, and I can bore the block myself or get a mechanic friend to do it for me for cheap.

Yes it does. That's one thing I can really hand to you man. Misfire notwithstanding, this engine always sounds soooo happy. It revs freely and just sounds happy as can be to push the boost.

/threadjack

I dont see a clutch on the list but i'm assuming its on there.

Wait you are willing to spend $179 on new pistons and rings that are not forged? Honestly at that point save up an additional $200 and put in supertechs while the motor is apart.

I was wondering/planning to do the same thing.

My buddy who's built a few engines said that if you pull the pistons out of the cylinders there's no way they will go back in and get a decent seal. He recommended strongly to do a re-ring. If I do any of this (rods only, keep pistons) I will be buying one of the ball honing tools to do a quick re-hone.

Because that re-ring set, including MLS gaskets, is slightly cheaper than the gaskets I have to pick up off of Rockauto.

Secondly, as I mentioned above, I don't want to put anything high dollar into this first rebuild. I am looking for Cheap Shit I can break and not panic going "Oh shit, those were $400 pistons!!!"

I'd put new cam seals in too while they're easy to get to. I have some rings in my trunk right now for standard bore nrg i think. I was going to use them on my build but went balls out on my build instead. original plan was what youre doing. I should havea stuck to it. lol.

Interested in selling them?

First the link you posted is for gaskets, bearings and rings no pistons.

They come with the cheap steel top rings, easy to seal not real good on boosted builds tho.

Also steel rings will seal on about any crosshatch in a cylinder bore, because the rings are soft

A decent chrome-moly ring is a tad more touchy to cylinder crosshatch and hone grit used.


Also please inform me how you will bore a block over sized, or your mechanic friend will.

Or did you mean hone?

Lulz. Linked the wrong auction.

Much <3 Bogus, going some variant of chrome-moly rings then. Thank you very much for this info!

Trashing boring plans, just going with honing the stock bore and stock pistons. Mainly threw them out there at cheap pistons, but those are cast, and not hypereutectic from what I understand.

If you are going to tear into your engine, might as well make it bulletproof.


Doesn't make much sense, and could be more costly to trash NPR pistons and have to replace them, since with the cost and bore after trashing stock pistons in a fresh honed stock size block could be the price of nice forged pistons that can take more abuse.

Lol...in do this too...everytime I build a engine It starts out budget minded then I get in the "might as well do this while im at it" state of mind...next thing you know a simple re ring is a motor bully to the hilt...

that's why I see this forum split between 2 different kinds of builds:
"complete" build guys who spare no expenses and have baller engines
"semi-buit" guys who do rods and refresh everything else including rings, bearings, etc.

Any less than "semi-buit" and you're just lazy and cutting way too many corners and being foolish

Ideally you want a "complete" build.

If you track the car you NEED a complete build.

Gonna end up going semi-built.

Once I'm ready to seriously track it though, I'm going into the "complete, no expenses spared" category.

(Read: I'm going to build my current engine to get a feel for the process/experience with cheap shit, then find a good BP block and go crazy with the expensive shit when I know what I'm doing.)

Just wondering, what is the purpose of your car? Not sure what you mean by "seriously" track...whether that means tracking at all or something else.

Either way, I'm confused that you're willing to dump all this $$ now only to throw it away and re-do everything again, re-iterating AlexL's point back on 1st page.

If you're planning on inevitable failure or re-doing things, what's the difference to you in running ~200whp now and letting the stock motor take it's course and then rebuilding vs. getting that extra 50 whp and throwing all this $ that could go towards your build in the future?

I've done everything on this car twice, Rkim.

My first turbo setup (Which I'm running right now) is a ch..ch...churbo off eBay with a BEGi mani and a homemade downpipe/exhaust/etc.

My next turbo setup (which I'll be installing shortly) is a Precision 4828 with Artech goodness with some very specific stuff that I know I won't be replacing.

If I have never done something before, I do it with cheap shit to learn about it (<$500 in this case to do what I'm talking about with 18psi), then once I'm certain I have it right, dump big money into it. If I tear up cheap shit, I could care less. And yes I've broken a ton of cheap shit on this car at this point, and don't regret "wasting" that money - it was to learn how to do it.

If you are going that low budget with the turbo (you should probably be spending that much money on a proper tune if you are going to track the car) don't do a thing to the motor, run it at 220hp as previously suggested until you start to dial up the boost and wind up damaging a piston (that would hapen on an oem or forged piston anyways) and learn all you can with the motor you have.
on the mean time save your money for for an engine manegment, tune, cooling and build that you can flog for 3 hours on a track day and drive home when you are done.

I think people here are mistaking my intentions. The whole point of this exercise is to learn how to rebuild the engine and, more importantly, if I should even be rebuilding them in the first place.

If rebuilding an engine turns out Not For Me, I'll just pay for a pro to do it (TSE? Bogus? Local? There's lots of places to go for it). But the idea is to learn how to rebuild an engine with Cheap Shit(tm), not to get some godly bulletproof engine. FFS, I was seriously considering rebuilding with an eGay kit.

These are the rings I ended up using. And they were even pre gaped to what I wanted for standard size pistons. Just used ball hone to freshen up the bore.

SEALED POWER Part # E551X

(.018 Top/.022 Bottom out of box Spec)

I did exactly what you did except i just rebuilt my engine stock. I cracked a piston though. FYI i spend about 450$ on everything to rebuild the engine including machining the head true. Don't forget the engine break in fluid (zinc additive) 2 oil changes, 2 oil filters, new tranny fluid, about 5 cans of carb clean, box of rags, rubber gloves, couple tubes of RTV, red Locktite, assembly lube, engine stand if you don't have one. Id also get a shop manual also just to verify correct torques and sequences. Don't forget some emery cloth (2000 or 3000grit sand paper) to polish your crank a bit. Check your crank and make sure you don't have any gouges or else you might have to get your crank turned and then the bearings you buy now will be too small so you will have to get new bearings. One thing i didn't do that i wish i would of done was get a new oil pump.

One tip with regards to installing the bearings. MAKE SURE your fingers are effing clean before spreading the lube. If need be, put on new gloves each set of bearings. I learned the hard way and had to purchase new bearings because i smeared some shit in there. Also mark your mains in numerical order so you don't get them mixed up.

Last but not least have fun and listen to some music. Where in Washington are you located?

The shop I'll be using is located near Ellensburg. And thanks for the advice! I'll be definitely using it all!

Forgot a couple things. Pour the zinc additive in your oil filter. Prime the engine until you get oil pressure WITHOUT spark plugs installed. Continue this for maybe 30 seconds to a minute. No problem. If you really want to be ninja get some platigage and make sure your oil clearances are in spec. Ill pm you my number if you have any questions just hit me up.

Thank you, it is appreciated.

I think Bogus meant that the chrome moly rings are more sensitive to the hone and crosshatch being just right or they won't seat well. Re-read what he wrote.

Right, but they are better than the other ones posted