86 Engine Failure, typical reasons?
 

Thought Id ask the guys over the US on your experiences with engine failure.

Considering on getting one if my MOT on my spyder fails due to corrosion.

Ive been considering the following cars and i know ill probably wake up an ongoing age old argument. ND vs the 86.

Im really wanting the 86 given its less common than the mx5, but hearing about engine failures is putting me off as well the dull steering feel of the ND.

Is most of the engine failure attributed to the oil starvation whether or not its FIed?

I thought getting opinions here will help.

Its going to be my daily driver for the first 4/5 years, with the occasional spirited driving since their sports cars. after those 4/5 years ill be looking on taking them to track days. I plan on getting the car on finance so having a reliable platform will be essential. I dont plan on going FI, and at most will do the exhaust and header tune to fix the torque dip as well as get an oil cooler.

Im mostly worries that ill blow up the engine and then not be able to get a replacement given their prices, so on that basis im more likely to go with the ND and bite the bullet on the issues with the transmission, since the fix is more cheaper and it seems like its less likely a transmission failure to occur than an 86 engine failure.

IMHO, the most typical reason for engine failure for non-boosted engines on this car has historically been, and will continue to be:

The money shift.

I would be willing to bet that this single factor outweighs all the RTV issues as well all others combined. Factory defect rates on this car are in line with all modern car manufacturers, and forums tend to not be representative of overall market figures.

All of this ^ ^^^^ All day long THIS.
And...
Modifying beyond the design limits, be it FI, tuning, or or just messing with things that don't need to be messed with.
Of course then any failure is because the engine is crap and the company has no idea what they are doing.

I disagree. As someone who runs around with groups of other twin owners who track, autoX, do TT/TA. Never seen an FA blow from a money shift. I've done it twice, both times hard enough to spin the car.

I'd say it is poor maintenance.

I've not money shifted on this engine (yet and hope never) but I have cracked a piston once doing it on an STi. It does seem to be a common mishap that leads to failure.

I wouldn't be surprised with money shift being a top contributor, but I can never get over how many people beat on these cars, and don't maintain them as they should.

In short, I would not be surprised in the least if user error were #1 by a good margin. That is most common with ANY car on the market.

From reading this forum I would say the most common engine failure is from bringing it to the dealer to get a valve recall done.

I definitely don’t intend on going more than stock ideally. But at most would do the following mods I listed to improve the torque dip and prevent oil starvation issue.

I hear the standard service interval is questionable. Over here i think its 9k miles. I’ll definitely look for MY2015 and above but say if the services have been done but its been done accordingly to the manufacturers interval even though the actual interval thats optimal based on forum is around 4k, do you suggest that I still consider it?

I’ll definitely look at models on or after 2014 MY.

The interval is fine unless you are heavily tracking, live in the desert or regularly drive at -40 degrees.
There is zero reason to service more on a daily driven street car.

I dunno where you picked up 4k

Guys have tracked with E85 and done 7500mi intervals and UOA's came back fine. Just use decent oil that meets the requirements specified in the manual and you will be fine.

Any links to follow on this?

We start to see oil dilution after 2K miles, sometimes at just over 1K miles on big built turbo engines. That said, I've never run it on an FA24, but that is a LOT of miles on E85.

I'd have to find the UOA thread. There are a few big ones with lots of samples to go off off. I only run E85 on track as it's hard to get here, there are some that use it almost exclusively that have done UOA's.

i don't really know where the idea comes to mind that the service interval is questionable.

granted, i change my oil around 5k miles, but i readily admit that it's always been more for my peace of mind than any factual/mechanical reason.

i think getting a 2015+ model is a good idea, as it gets past the new platform teething issues that occurred, and takes advantage of some of the incremental improvements that were made. but by no means do i consider any '13-14 unreliable by itself. i would absolutely recommend a properly-serviced '13 over a non-serviced '18 with the same mileage/condition.

The amount of bearing related failures like rod knock on these is staggering, thats just how it is, not exactly helped by the recall thing. The later ones are much rarer but seems better built in most ways, they changed quite alot of small things over the years.