Looking for engine options

[Kenstaki]

Hi Ladies and Gents,

My first dip into motor sport has resulted in my engine developing a knock. I'll be back though!

I had checked the oil incorrectly so it was starved during the runs and that's resulted in engine damage. After topping up the oil, I was able to nurse it back to Melbourne from Shepparton.

My brother has swapped a few engines in recently, he's got all the tools including the hoist.

I'm just wondering where I can purchase a used engine in good condition other than looking through our classified sections or possibly MX5Factory? I'm looking to keep it stock.

I've got the NB30P1 model, so as I understand it, any 1.8L from '97-00 would fit?

What other details should I be looking into?

Cheers,

Liem

[Zcootz]

What do you mean by you checked the oil incorrectly ?

[Kenstaki]

Yeah, I expected to be chastised about this. I put dip stick in, wipe, put back in and read. Oil was present on edge of stick but not on the flat surface of the stick. So yeah, stick must've touched oil on the way in.

[Mr Morlock]

Why would you change the engine? Engine changes without a bucket of knowledge and even with a lot knowledge is a big undertaking. You will now need to see if the engine is worth repairing or to find a replacement. By all means talk to the MX5 factory and they will tell you the lay of the land.

[Charlie Brown]

Sorry to hear of your mistake but it is a good lesson for all those thinking about going to the track.

The best insurance you can have to walk away smiling after a track day, is to change the oil and filter before each event. Use a high quality full synthetic oil and make sure it’s at the top mark on the dip stick. Check it through the day and top up the level should it drop below that top line.

On the NC’s have it a little above the top line to help prevent oil starvation in high G left hand corners. Drill two small holes in to dip stick, one at the bottom mark and one at the top mark to make it easier to see the oil level as the oil is pretty clear when new.

I don’t know the VIC scene but I’d suggest you ring around a few wreckers to find another engine. You could also pull the engine down, grind the crank and put in new bearings and rings.

[Kenstaki]

Thanks for your thoughts guys,

My thinking is I have a few options

1. Sell car. Buy another.
Pros: Avoid risks with options 2 and 3.
Cons: Lose money on sale. Grown attached to the car.
2. Open up and rebuild.
Pros: Learning experience. Potentially finding damage is not as severe as suspected.
Cons: Domino effect, repairing bearings lead to machining block/conrods which lead to other repairs etc. Complex modern Japanese motor difficult to repair. Would not be able to supervise this myself so my wallet is at the mercy of a mechanic.
3. Swap for another motor.
Pros: Have access to tools/experience needed to perform swap.
Cons: Finding a good condition engine in Victoria or importing interstate. Potentially other problems with a new motor that I haven't considered - this is the main reason I'm posting to this forum seeking thoughts from people who have done this swap before?

What are your thoughts?

[Aussie Stig]

Check out Emily, she has an awesome engine change thread.

[93_Clubman]

I've got the NB30P1 model, so as I understand it, any 1.8L from '97-00 would fit?

NB30P1 was '98-'00 - there's a NB30P1 motor for sale near Frankston:
viewtopic.php?f=44&t=54825

[Kenstaki]

Check out Emily, she has an awesome engine change thread.

Do you have a link mate?

[Aussie Stig]

viewtopic.php?f=57&t=49039

You gotta love a girl that gets her hands dirty.

[emily_mx5]

Nawwww thanks guys! It's nice to know someone reads my thread haha.
Which reminds me I really must update it!

Back to this topic, what I would do in your circumstance,

Take the engine out yourself. This is easy.

Take all the ancillaries off yourself. This is easy but make sure to bag and tag everysingle nut and bolt as you go, and take pictures of all brackets so you can easily put them back in the correct orientation.

Take the main parts of the engine apart yourself.
Moderately difficult, you must be careful and organised, a workshop manual is a must.

Then you can take the main bits to an engine shop, and get them to machine it and assemble it.

Then you can put the ancillaries back on and put it back in the car yourself.
This will save several thousand dollars of labor, and you wil learn heaps!

[manga_blue]

Reasonable NB8B (VVT) engines sell for around $1,500-2,000 these days. This is probably your best and cheapest option for a road car.

If you want to rebuild then let's be honest: it's not a DIY job for a beginner. You will need to have done a few simpler re-builds or engine overhauls before you tackle an engine that will see track use.

You'll also need quality tools and measuring equipment. That includes a clean dedicated workshop and bench, sidchrome/kinchrome spanners and sockets, a good torque wrench or two, good verniers or micrometer and a good parts washing setup. I'd personally say an air compressor is a must too.

Machining would be your biggest single cost. There'll be at least crankshaft grinding, head shaving, block decking and cylinder honing. Depending on the damage there may also be line boring and cylinder boring. If you're going to keep tracking it then balancing is worthwhile too. So $600-$1,200 in machining. The bare minimum parts will be main and big end bearings and thrusts, piston rings, assorted nuts and bolts, welsh plugs and a full gasket set. Also consumables like RTV silicone, assembly oil and loktite. New pistons and new oil pump are not out of the question after oil starvation. It's normal to bring forward the scheduled maintenance a the same time: belts, water pump, hoses. So without labour you're up around $2,000.

Labour for a DIY is around 40-60 hours to do it meticulously. A good mechanic may take a quarter of that time but a good mechanic won't come at the lowest hourly rate. There's also the time spent delivering and collecting parts from the machine shop and getting the other bits and tools.

The benefit of a build is that you can use better quality components and improve the general quality of the build over the production standard, typically by balancing, port matching, removal of casting flaws, and you can do some subtle reliability or performance mods as well, e.g. porting, oil pump mods, coolant re-route, etc.

Edit: First statement was wrong. I had an idea that yours was an NB8B. It's NB8A. Prices are about the same and it's older so you need to be more careful about the provenance of the engine. Otherwise everything else is unchanged.

[emily_mx5]

Yes an engine rebuild is not a simple DIY begginer job, that's why I suggested doing some disassembly DIY then leaving the rest to an experienced professional.

[Kenstaki]

Reasonable NB8B (VVT) engines sell for around $1,500-2,000 these days. This is probably your best and cheapest option for a road car.

Thanks for the detailed advise. Where did you get these figures from?

[Kenstaki]

I've got the NB30P1 model, so as I understand it, any 1.8L from '97-00 would fit?

NB30P1 was '98-'00 - there's a NB30P1 motor for sale near Frankston:
viewtopic.php?f=44&t=54825

Thanks for the lead, it's been sold unfortunately.