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my rings are on the way out, bluey grey smoke blows out of the exhaust,
and has been chewing oil like no tomorrow, i have chucked some stop exhaust smoke in, and planing to put some thicker oil in.

me and my stepdad are predicting 6 months intill it gives way.

i have started looking into an engine rebuild, the engine has 128xxxkms on it, is it worth rebuilding, or should i buy i lower k engine (current engine has had a bad life)

now, i cant turbo the engine (and that is my intentions once i get off them), due to being on my P plates, so should i even bother with a rebuild ? or just buy a low k.

which parts do you think i should consider in the rebuild, so far on the list are:

forged pistons - 11.1 compression
A beam Rods
ARP Studs
unshroud valves
back cut stock intake valves
Cams
Cam gears
550cc injectors

your thoughts guys?

how on earth did that happen??

these engines are meant to get past 250,000ks without much troubles

SuperMazdaKart wrote:how on earth did that happen??

these engines are meant to get past 250,000ks without much troubles

i know, maybe to much spirited driving and previous owners mis treating the engine, i dont know but this is the outcome, and i have to face it

A rebuild using the parts you describe will be quite pricey, and mitigates against an eventual turbo install.

For much less - similar to the $$ you will spend on an import motor - you could rebuild the existing donk.

Things you would need to do...

Valve seals - these may be what is leaking. A head rebuild will cost you around $500, but it will be good to go for another 200k kms.

Piston rings - you probably don't need new pistons (upsize to .020 oversize), just re-ring the stockies with ACL rings for less then $200.

Gasket set - you will need a gasket set, that will cost around $250 for the complete engine.

If you just do the rings (and the bores are in tolerance - which they probably are), you will be in and out in a weekend. The head work will take at least 1 working week, so you need to decide if you want to do that. When the head work is being done, it is also a good time to consider getting the ports cleaned and the flow improved - but more $$$ (around $800 for what you want done).

I suppose what I am saying is that for similar $$ to an import, you can have a better, stronger, engine that you know will last. And you get the satisfaction of doing it yourself.

If you want to spend more $$$$ you can drop in the 11:1 pistons ($850), A beam rods ($1500) and get the whole rotating mass rebalanced (with that new lighter flywheel ($450) and clutch ($250) you're also going to buy) for $250ish.

Cams will be around $1000, and NA cams need adjustable gears to adjust the timing to be best use in FI engines (another $600).

Or you can go the turbo route with an import donk and accept that it might die, one day, in a couple of years and you will worry about it then because it only owes you $1000 plus installation costs. NA is fun, but it is much bigger $$ for less useable power than the numerous turbo installs getting around. If you want to go turbo, don't dick around with the hi-po NA route, build for the turbo install.

But if you are confident that the existing engine is good (I know you have your doubts here) and you want to DIY it, then it may be better to rebuild spending the $$ on porting the head, etc. (or buying a later model head with better flow - 01+ I think?)

My 2c worth since you asked for opinions.

If you plan on getting rid of your engine, ill buy it off you.

go manual as well if you get a replacement engine

adamjp wrote:Valve seals - these may be what is leaking. A head rebuild will cost you around $500, but it will be good to go for another 200k kms.

That getsmy vote too, doubt it'd be the rings at 128K on a jap engine!

go manual as well if you get a replacement engine

Is this a reference to there being an automatic gearbox in the car?

If so, your rings will probably be perfect - autos don't let the engine rev hard enough to do massive damage to the rnigs in 130k kms.

Do the long compression check to see if it is the valve seals or the rings.

how about fitting something like an rb30det in there?

I'd like to see that on his P's

just rebuild the engine you already have in the car at the moment mate. save you some cash, only problem is how long you can afford to keep the 5 off the road.

drive without P plates..

not too long until you're off ur P's crocs

i get my fulls mid next month

i've got 2 years left sliq, if i was closer i would do the turbo rebuild

thanks for your 2c guys, i'm willing to spend a fair bit on a n/a rebuild, i love the thought of owning a mx-5 that would rev at 8-9000rpm, and its an option many people overlook due to the easyness of f.i, however if i was to build an engine with the desired parts + bore, whats stopping me from chucking on a supercharger? would the piston compression be too high for this?

and yes, when the rebuild comences, a 6 speed is on the cards along with a emu, now i just need to find some money

anyone know how much it would cost me to get the block bored out?

JSE wrote:just rebuild the engine you already have in the car at the moment mate. save you some cash, only problem is how long you can afford to keep the 5 off the road.

i cant afford to keep it off the road, its my daily

Crocaine wrote:i've got 2 years left sliq, if i was closer i would do the turbo rebuild

thanks for your 2c guys, i'm willing to spend a fair bit on a n/a rebuild, i love the thought of owning a mx-5 that would rev at 8-9000rpm, ....

My friend ......you're fantasising here . At that sort of RPM it isn't going to last too terribly long . And for a daily driver, you are going to have to make too many compromises to make it drivable.

or if you do manage to do it......you may as well buy that Ferrari or Bullet intsead of spending the money on 1 engine

just my 2c