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-   -   99-05 Pistons (https://www.miataturbo.net/wtb-7/99-05-pistons-41165/)

Rallas 11-14-2009 03:59 PM

99-05 Pistons
 
I am rebuilding a 96 1.8 and am looking for used pistons that someone might have laying around from an upgrade to higher strenght pistons/rods.

I messed up one of the spring clips that hold in the #3 piston on my set of pistons. I figured if I am going to look for a usable, used set I might as well look for the slightly higher compression ratio 99-00 or 01-05 pistons.

Full_Tilt_Boogie 11-14-2009 04:19 PM

Youre rebuilding an engine with used pistons...

Tw34k 11-14-2009 04:29 PM

:facepalm:

Rallas 11-14-2009 04:34 PM

Yes rebuilding. If you are not asking 250+ HP from a block and everything looks good and is in spec as far as clearances you do not have to have new stuff. Replace the consumables like rings and bearings give it a fresh hone job and you are back in business.
You don't have to stick new pistons in unless you want bigger ones or the old ones are worn beyond spec.

Thats why I am trying to see if anyone has pistons that are still within spec that they took out when they upgraded to bigger/stronger pistons.

Full_Tilt_Boogie 11-14-2009 04:37 PM

I find it very, very unlikely that your cylinders and pistons from a completely different motors will be within spec of each other. Reusing the pistons that came from that motor is one thing, but putting used pistons from a different motor is not something I would ever do.

18psi 11-14-2009 04:39 PM

Is your car n/a or f/i?

If its n/a I'd go with the newer year 10:1 compression pistons.
If its turbo I'd get replacement 9.1:1 pistons.

And I agree that as long as you're putting in good condition pistons there's no reason to buy BRAND new ones unless you're doing a full on build.

18psi 11-14-2009 04:40 PM


Originally Posted by Full_Tilt_Boogie (Post 482478)
I find it very, very unlikely that your cylinders and pistons from a completely different motors will be within spec of each other. Reusing the pistons that came from that motor is one thing, but putting used pistons from a different motor is not something I would ever do.

Why not?

Ben 11-14-2009 04:45 PM


Originally Posted by Full_Tilt_Boogie (Post 482478)
I find it very, very unlikely that your cylinders and pistons from a completely different motors will be within spec of each other. Reusing the pistons that came from that motor is one thing, but putting used pistons from a different motor is not something I would ever do.

Relax boss. A hone and some rings, and all is well.

Rallas 11-14-2009 04:47 PM

If I can find a set that has the right measurements to be within spec to fit my cylinder bores with the right clearances there is no difference in fitment in installing a new (unworn) piston and a piston that is within spec as far as diameter, taper and out of roundness. I realize the pistons that have been zinging around in my block for the past 140k are probably the best fit. I'm not just looking for any old ass useless worn pistons to just throw in and hope they give me higher compression.

Do you have any experience as to why this cannot be done with a properly fitted used piston?
Unless you have some experiece or reason as to why this cannot be done or have a set of old pistons you want to sell me for cheap, please keep your comments to yourself. This is the WANTED TO BUY section. I am not asking for advice, just trying to get cheap parts.

Tw34k 11-14-2009 04:55 PM

I would not trust putting used pistons in my engine that were possibly beat on by someone else, If that's what you realy wish to do then more power to you and I hope all goes well but imho id cut corners on external things before I ever did so on parts that can cause a catastrophic failure. Better safe then sorry yah know?

Full_Tilt_Boogie 11-14-2009 04:56 PM

I just don't like using pistons from different motors because no two motors will wear exactly the same way. The BP doesn't have the best rod ratio in the world and I would imagine that you would get some tapering pretty easily. Its not that its impossible or even unlikely, I just personally wouldn't want to risk it.

Tw34k 11-14-2009 05:03 PM

How much can a set of oem pistons cost.. even if the dealer is a thief im sure you can find a online oem parts store that will surly sell them at a decent price and they come with piece of mind.

Rallas 11-14-2009 05:15 PM

If you look at the cost of getting new OEM pistons, I might as well go all the way and get forged pistons and if I do that I might as well get upgraded rods as well. That puts me way beyond just doing a rebuild on the 1.8 that I am swapping into my 91. For now I am building a dependible NA, with aspirations to one day to a sub 200hp turbo setup.

Tw34k 11-14-2009 05:29 PM

Honestly I dont know how sturdy the rods are on mazda's but ive seen stock motors with ONLY forged pistons make just over 400 whp and last.

Id put in some forged pistons and be done with it in your position if the rods are able to handle any power

Full_Tilt_Boogie 11-14-2009 05:35 PM


Originally Posted by Tw34k (Post 482509)
Honestly I dont know how sturdy the rods are on mazda's but ive seen stock motors with ONLY forged pistons make just over 400 whp and last.

Id put in some forged pistons and be done with it in your position

The rods fail before the stock pistons do, I saw someone recently running some pretty serious boost with H-beams and stock pistons

Tw34k 11-14-2009 05:50 PM

new oem pistons and aftermarket rods ftw then! :D

18psi 11-14-2009 06:01 PM


Originally Posted by Tw34k (Post 482509)
Honestly I dont know how sturdy the rods are on mazda's but ive seen stock motors with ONLY forged pistons make just over 400 whp and last.

Id put in some forged pistons and be done with it in your position if the rods are able to handle any power

Dude no offense, but you really need to stop giving advice like this out, its completely bullshit.
With these cars its exactly the opposite of what you said.

I know you made another post changing that, but c'mon: some noob will search threads and happen to come up on your post. Reads it out of context, fucks up, and its your fault.

Don't get mad. Just stop.

Originally Posted by Tw34k (Post 482499)
How much can a set of oem pistons cost.. even if the dealer is a thief im sure you can find a online oem parts store that will surly sell them at a decent price and they come with piece of mind.

They cost over 450 at the local stealer. (around here)
They cost about 100 each online. Most places online (aside from dealerships) sell no-name brand shit. NOT OEM. Meaning it could be some POS replica chinese shit. I called around and asked around.

For that retarded price you might as well go forged. Then there's the issue of size: there are no forged pistons in stock size. So you have to bore. Blablabla and this shit adds up.


There is no legitimate reason to not be able to re-use used stock pistons.
Aside from the bullshit "I just wouldn't be comfortable with it" opinion.
If they are from a lower mileage unmolested car, look great and measure up to spec they're fine.

If you can prove me wrong I'll shut up.

Tw34k 11-14-2009 06:23 PM

I never told him his rods are not going to break.. i simply said that ive seen some motors that handled over 400 on stock ones.

I also CLEARLY stated multiple times that i dont know the power handling capabilities of stock rods in these engines, and once i did research them a bit i quickly reinforced the point that rods are needed in these engines, Im not here to give anyone any strict mazda related info.. im here to learn about them..

If it makes you feel better ill even put it in my goddamn sig ( I dont fully know mazda's yet )

albumleaf 11-14-2009 06:31 PM

Posting anecdotes about other motors in a thread like this is retarded, but I guess you already realized that.

Rallas 11-14-2009 06:40 PM

Iv'e always wondered why people are such dicks on this forum. I am starting to see why.

If you just admitted that you do not know these engines, then please do us all a favour and shut the hell up. I did not ask for your opinion! I am looking for a set of good used pistons and thats why I posted in the WANTED TO BUY forum.

If I wanted your opinion I would have asked somewhere else in a forum that would actually discuss this crap.

Bottom line, if you don't know what your are talking about and do not have any applicable experience other than "you read somewhere" or "you think" or "you FEEL something", FEEL free to keep it to yourself.

Now if the moderators could please kill this thread so I can post a new one to request for some damn pistons without getting any opinions on the matter and waisting my time!!!!


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