Why do our engines keep blowing up?

[Carl]

Most of the engines that have done that sort of mileage will not be 3rd gens,even here in the UK it is not unusual for 1st and 2nd gens including turbo\'s to do 100,000 miles and beyond.
Kind regards
Carl

[Robertio]

The sceptics can find the thread here it is in the 3rd gen forum and most are 3rd gen owners.

Once they start modding them they do seem to go through engines like us :o but if run stock quite a few are making big miles.

[Carl]

Still alot on much lower mileage though.
I think that the type of fuel can have an effect too as our fuel up until recently had a higher sulpher content.Also as was said earlier in the States people do much longer jouneys with steady driving than in UK,here it is often alot of stop starting and shorter trips.
Kind regards
Carl

[Fish]

Jason, most of the aftermarket ECU\'s will retard ignition/add fuel as temps change. You can normally adjust what temps it starts adjusting things.

Dan

[John Yorke]

As we are talking now about stock engines, I feel that most failures are down to lack of propper maintenance. Picture this: Joe public has seen F&F, 2F&F wants an RX - best buyes are from the land of the rising sun - loads of cheap auctions [can buy it cheap]- buyes the car unseen [ not from a recognised dealer] chances are it\'s a dog - arrives in the UK [for very little money] gets the SVA/MOT drives of into the sunset only to find it ends in tears - no or very little servicing car goes pop - people start moaning - asking advice AFTER the event instead of prehaps spending a few more £££\'s and doing it through a dealer. I think you will find most cars go pop shortly after landing rather than the long term cars that have been sorced correctly and looked after.

If we are talking about modded cars - if the work is carried out within the \'comunity\' chances are you will get reliability PROVIDED you stay within the peramiters if you are pushing these limits [going for the big numbers] then I feel we have not got the experience yet to go for them - as captain Kirk said \'To boldly go where no man has been before\' maybe the way forward is to share the knowledge - after all are we not all seeking the same goal?

[g11ary]

have to agree with what John says.
When Carl built the engine for the black car, his first words were, its unchartered territory I cant put my hand on my heart on say it will last more than totb but would like to see it last longer. Totally acceptable if your doing sometime totally radical and a first time attempt.
Im comfident that the same engine placed in the yellow car would run for miles. Its all realtive to the amount of stress you put your car through, somewhere in the middle there must be power and reliablity IF its mapped correctly and built to a high standard.
Spend ya money and make your choice.
You will never know the secrets of the top power builders as it is years of time and money that has taught them, and to most its there living. But its nice to see  the rotary scene moving forward on mid power cars which I have seen in the last 3 yrs.
When I first went to Rotechniks and had a single turbo conversion it was a rareity now its norm, when I said I wanted 400 bhp most poeple were amazed now its ok.
We have come a long way thanks to forums like this and the peeps that contribute.

Just keep it coming, one day I might even learn something :rollin

[Glenn Butcher]

I think I have some pretty good feedback on this Thread - can you guys who have lost engines confirm what spark plugs in the Leading and Trailing that you are running?

[maximtaylor]

9\'s for me

[Glenn Butcher]

Hi Max,

OK I think I have some pretty conclusive information on this for you.  

I\'m not saying it will stop engines from popping - but it has gotta help in a big way.

The 9\'s all round are no good for high speed running, they are too warm.  You really need to get yourself a set of 11\'s (I think Ant use to run these).

Please check out this Thread on Ausrotary - guys out there have been a great help:
http://ausrotary.dntinternet.com/forums/viewtopic.php?p=182483

Thinking about it - (as RICE RACING has mentioned), I use to actually run 10\'s in the leading and 11\'s in the trailing for my non-turbo RX-2, and 11P\'s all round in my RX-4 racecar.

Problems you may have with the colder plugs is fouling up for running around town etc. - i.e. that is why Mazda puts 7\'s and 9\'s in as standard.

But for racing and high speed runs cold plugs are essential.

Let me know what you think.

[Carl]

Already ahead of you on that one Glenn.
My experience in racing has taught me that.
kind regards
Carl

[Glenn Butcher]

G\'Day Carl!!!

Where\'s your post then  

[Carl]

Originally posted by Carl
Hi Glenn,
I am in complete agreement with you that tuning is critical on the modified engines, but so are many other things like fuel,how the car is driven,maintenance,boost control,temperature control of coolent,temperature control of intake charge,injector sizes,fuel pressure both from the pump and regulator,sparkplug quality ................and  the list goes on.

Here Glenn,
Here is my thoughts that I posted earlier which talk of plugs.
I do not wish to give away all my secrets now do I?
It is not just plugs that are the answer,the whole package is.
Kind regards
Carl

[Glenn Butcher]

 no worries, but I think the plugs would be a pretty major thing - given the circumstances of high speed running?

Especially if the engine is fairly new and has a decent map in it etc.  

I just can\'t believe that they are that weak (which I have never believed of course).

Max, did this happen to you recently - and how many miles were on the engine?

[maximtaylor]

To be fair the engine had 45k miles on it. Thanks for the plug info, I\'ll look into this a little more.

BTW John, asking where the air temp sensor is - look under the plenum (tricky unless you take it off) and you will see a blue plug which goes into the third chamber back.

I can see mine, but then I don\'t have the rats nest anymore.

Regards

Max

[db2boy]

Lo,
  Indeed, I have now experimented with 9\'s,11\'s and 11.5\'s all round. 9\'s in my engine were OK to a certain point of boost and mods, 11\'s and 11.5\'s made a nice and required difference.  

As Carl says though, cant go giving everything away but in my personal experience and opinion the ignition side (obviously) makes major changes to running/perf. If you modifying you sure need to spend some bucks on plugs, we all know the rotary heat thing so why shouldnt these principles apply to a critical coponent like the plugs? Leads, believe it or not OEM Mazda FD leads when they new are not so bad on resistance, although there are better to be had - again in my experience had some junk from the US claiming to be low resistance, had some amazing leads from Japan that sure were low on resistance! If you cant justify or dont need a walloping ignition modules(s) then just make sure you check all 3 OEM ignition paks as often as is convienient.

Following the main point - tuning, tuning, tuning - and think about the systems and the demands you asking of them, how they effect localised components and the overall package. Yes putting on upgrade x will give you y, *but* how and why does it do what it does, understand this then, then  understand the continued affects.

Rgds

Ant