Engine died. Sad day.

[22Silver]

As title says, engine died.
About 140,000Kms on the clock, fresh oil, fully synthetic, 4000km's ago.
Don't know what happened but the oil pressure gauge fell to zero on the freeway, and then the car started knocking and pinging and rattling and sounding like death, a few seconds later I was having negatie surges of power, and REALLY hard knocking in the engine bay.

Pull off, there's no oil. Not sure why there's no oil but something didn't like being spun dry and killed itself.

So, I like the car and almost everything else is new (suspension, exhaust, radiator, wheels, tires, soft top, all filters, all hoses, control arms, and a few other bits and pieces) so I've decided to repair/replace the engine.

Basically, I was looking at building a stronger engine anyways, so I could rev harder and not worry about breaking things, and I figure I may as well go the extra mile now, instead of sticking stock parts back in, and then throwing them out in like 8 months.

Any advice/condolences appeciated.

I guess my question is, repair/replace? If repair, what are the weakest links in a BP4W that I should go about tackling? And if replace, where does one go about looking for a non-stock motor?

For either option I can go to my uncles garage (big garage in Drouin) and do a fair bit of work myself (guided by experts of course) and pay roughly $200 getting the car there and back, or I can just pay someone in the east to do it.

In short, I'm pretty bummed because my engine has bitten the dust, and I want to make more power once it's replaced/repaired, just as a consolation for shelling out so much money.

[Magpie]

What is your budget?

[dave2221]

there is a written off SE for sale

new motor, diff suspesnsion and brakes

TURBAN POWER

[hks_kansei]

Cheapest option will be to simply replace with a secondhand engine, the other option is to rebuild.

If you choose to rebuild, it's important that you choose now the future of the engine, things you might do in preparation for going turbo in future may be different to if you want to go naturally aspirated.

I would be checking what failed though, 140,000km is nothing for a BP, it should last a lot longer than that. Also also not fail as dramatically.
I'm going to suggest maybe the oil pump siezed, or perhaps the pickup got blocked by somthing.



A rebuild won't be cheap, bear in mind. There's a lot of precise machining to be done that CAN'T be stuffed up.

[22Silver]

Probably $4000.
My hope is to be able to salvage a few pieces and save some $$$.
I'm thinking forged pistons, stronger con rods etc.

This car will ALWAYS be NA. I have 3 years left on my P plates

I have read that a BP4W with a BPZ3 manifold is quite nice.

It could be the oil pump, I'll check once it's off the float and in the garage.

*edit
if it costs much more than $4500 I'll put the car off the road for a few months and save, I have a few other cars

[zossy1]

N/A limits your options a bit.

Second hand engine will cost around $1,000-$1,300 for a good one. Then you just drop it in (preferably after doing seals and a timing belt/water pump kit, which is stupid easy with the engine on the stand). So factor in $1,500-$1,600 for engine, consumables and your time. That's the easy/cheap option.

The stock BP can handle a few hundred more rpms on the limiter with a fair margin of safety. It can also handle some more timing advance and these things are not that hard to achieve (do a search for info). These things, plus a pod filter and decent exhaust, will yield reasonable power numbers.

There is lots you COULD do... figuring that your core is buggered (and if it ran dry, you won't salvage much), a new engine build will still require a decent core so you're still up for the $1,000-$1,300. You might find a high mileage core for less. Then it's a case of how far you want to go. You'll need pistons, rings, bearings, head and main studs, valve guides and seals as a minimum. In the top end i'd also suggest new valves and a basic valve grind, plus valve springs, retainers, SUBs, and a cam check (wear may necessitate a regrind or replacement). You would also be mad not to throw conrods at the bottom end while you're at it - they are so cheap and are a weak point of the BP.

So if you're doing all this, you might consider going 1mm oversize on the valves and/or running Supertech 11:1 pistons with an overbore. So there is head machining and block machining to factor in and the pricing for this work will depend on the quality of your core, as well as whether you overbore or go oversize on the valves (not to mention other headwork!), and of course some shops are cheaper than others... then of course you will need gaskets, water pump/timing belt kit, and the hundred other things you often forget until you are putting the engine together. PLUS you will still need to consider engine management - reflash, piggyback or standalone, and then the engineering requirements arising from that... And you could also go ITBs (I have a set for sale that would fit the NB8A! ;)

Check eBay, or websites like trackspeed engineering or 949 Racing for prices on the engine parts. Then call some machine shops for estimates on the machining work. In short, it would be easy to blow your $4,500 in a hurry if you let it get out of hand.

[22Silver]

Seems like a lot of work.
I only want maybe 20-30% more power, and a stronger less fragile engine.
The exhaust is new, I had a performance exhaust place modify an SE exhaust. (also copped a lot of 'wtf did you do that for' on that one)
The timing is advanced already (really didn't do much as a standalone modification)

It sounds like I could Probably hit 130-140kw without going fully forged?

[zossy1]

It sounds like I could Probably hit 130-140kw without going fully forged?

Without FI? Not likely.

130kw for a N/A BP is an a$$load of power and requires very high compression, extensive headwork, big cams and an enormous amount of tuning. ITBs are also more than likely going to be necessary to achieve these numbers without a turbo.

I have heard of VVT engines managing 90-93kw with a pod filter and exhaust. This is rare though and I have not heard of a non-VVT engine reaching these numbers without more extensive work.

I recently spoke to someone who spent more than your budget on a rebuild of an NB8A engine that included cams, mild head work and a compression bump with heavy duty bottom end work. He managed 109kw with a standalone and tuning.

[hks_kansei]

It sounds like I could Probably hit 130-140kw without going fully forged?

Without FI? Not likely.

130kw for a N/A BP is an a$$load of power and requires very high compression, extensive headwork, big cams and an enormous amount of tuning. ITBs are also more than likely going to be necessary to achieve these numbers without a turbo.

I have heard of VVT engines managing 90-93kw with a pod filter and exhaust. This is rare though and I have not heard of a non-VVT engine reaching these numbers without more extensive work.

I recently spoke to someone who spent more than your budget on a rebuild of an NB8A engine that included cams, mild head work and a compression bump with heavy duty bottom end work. He managed 109kw with a standalone and tuning.

Depends on where it's measured.

130kw at the flywheel would be about 95kw at the wheels.
Which is within the realm of cams/computer.


For reference, an NB8A with stock engine (just a straight through muffler) only makes just under 80rwkw. (my car, Road-Track-Rally dyno)

[22Silver]

Oh sorry, I meant HP. 140kw is too much at the wheels for a nooby driver like myself.

I'd be happy with 95kw at the rear wheels, although 100 would be nice just for triple digits.
I don't however want more power than the engine can reliably handle. This is a DD that does a reasonable amount of km every day (to and from work and then up and down Mt Dandenong most days)
I DO want the engine life to be measured in increments longer than hours.. Hence, I don't want to bump the rev limiter to 7400 without being absolutely sure it wont throw a con rod or whatever.

[Mr Morlock]

it just seems like a litany of problems with this car and a lot of money that has been spent on this and you are lining up for more. Sounds like an engine that is now beyond economical repair and what was the cause? No NB is worth very much in $ terms- great cars even standard and some people drive them that way for years. The wise thing to do is buy something that is unbreakable and leave it alone or use one of your other cars.

[22Silver]

it just seems like a litany of problems with this car and a lot of money that has been spent on this and you are lining up for more. Sounds like an engine that is now beyond economical repair and what was the cause? No NB is worth very much in $ terms- great cars even standard and some people drive them that way for years. The wise thing to do is buy something that is unbreakable and leave it alone or use one of your other cars.

I'm sort of at a point in my life where I still live with my folks (dad is a bit of a petrol head, did the same kinda crap to his Torana as a young lad and supports my projects with an extra set of hands whenever he can) who I might add both have NC's, so I have 2 other MX-5's to drive while mine is down and out. I also have enough disposable income to not really care.

There won't be many years left of "old man helping me turn screws, letting me use his NC when I turn the wrong screw" left, so I'm kinda lapping it up. Plus I'm really enjoying working on cars instead of guitars and computers. Bigger/faster/louder etc etc.

After several insightful posts and a little extra research it sounds like a VVT engine with cams, headers and ITB's can make 95rwkw with minimal headwork and probably doable without any forged.
Am I a fool for wanting to believe that?

[zossy1]

My head hurts

130 whp is fairly easy with some mild mods. That is around 95 kw atw and as noted by a previous poster, that's not a big jump on stock numbers.

Lightyear was basically seeing that out of a stock VVT engine with pod filter and exhaust, so yeah, it's possible. Just remember that the VVT swap is a little fiddily as if using stock ECU and loom, you will also need a matching immobiliser and key from the same car as the ECU.

[sailaholic]

Forget itbs just swap a stock vvt engine and ecu in with decent exhaust and call it a day.

It's daily dríven on low budget don't go stupid. You keep saying you want a strong engine. Well the stock engine was strong, sure the rods are a weak point but not in Na form.

And if your bashing the limiter all the time your doing it wrong anyway.


Sent from my iPhone using Tapatalk

[Pamex]

Mmm, I disagree Morlock. Sure, a lot of money may have been spent, but sometimes it's not about that. Don't ever ask me how much I'm spending on nuts and bolts alone for my resto of mine. :p

Ok, just realised the following sounds smart arse-ish, but it's not meant to be. Just throwing things out for you to factor in to your costings.

The cheap option is definitely to whack in a second hand motor. However, gone are the days of ridiculously cheap engines for these. How good are you on the tools? Are you going to be able to do pretty much all the labour yourself? Or are you going to have to pay quite a bit of labour? It's all stuff to factor in.

I'm pretty lucky having a well sorted home workshop, heaps of spares and literally tonnes of racking of hose clamps, nuts, bolts, assorted fasteners (I'm a freak and HKS_Kansei is patient), spare hosing etc. Are you going to have to buy everything from scratch though? Sounds crazy, but it all needs to be factored in. It's the little stuff that eats your money.

I recently priced a second hand NA6 engine and some bits to keep it reliable (belts, timing kit, fluids, etc.) and that came to around $1700. For parts alone. I haven't priced a BP or the like, but I doubt you'll be getting out of it for under 2k for just parts, if you're doing it properly.

Now, to rebuilds: Will you be assembling it yourself? Boring, honing, price of parts etc. is pretty much the same fee no matter how big you go. But, well, you can't go crazy with these motors and expect reliability. I have all parts ready to do the bottom end on a motor in my garage currently to stock specifications including machining. All up, TRADE price, was just under $2k. There's still more to buy. I still have to do the head, that's not included. Just under 2k for a stock old-school bottom end (simple as can be). Depending which way you want to go, are you going to have to factor in an ECU etc.? Do you have all the required tools to assemble it? Do you have the time and patience? Is someone going to be happy for you to plonk stuff in their workshop whilst you do it? Most importantly... are you going to be able to keep everything clean (crucial) and together in someone else's workshop whilst you're not there?

I'm not trying to be a smart arse, just throwing things out there for you to factor in.

If you're doing an engine build yourself, I reckon factor around 2.5 - 3k minimum unless you can get trade pricing. There'll be tools you need to buy, sealants, replacement items, fluids, etc.

What would I do? If I was chasing more power, I'd be pulling the engine out and rebuilding it to whatever specs you want. Assuming it doesn't have a cracked head or block. First though, I'd be chasing why it shat itself.