CF_Koifry

I've had my RX8 since lat april, but since my post count is low I can't seem to post outside of this forum, so I'll pose my questions here. After searchng through the previous threads with much chagrin, I'm finding lots of conflicting info (as with all automotive forums) and just wanted to touch base to see if anybody could better clarify my findings.

Alright here goes

I have an rx8, fun stuff...yay, 2006 Shinka #886

Well, it's about to roll over 80K and I've done all the usual maintenance. Spark plugs, plug wires, coil packs, kept the oil changed and at proper levels (Check it like the owners manual says, every three fuel stops of so), and kept a clean oil filter on it. That's the info on my maintenance...

Now, I went to my dealer and asked about the engine warranty, and I have until November before Mazda tells me they won't warranty the engine. Car runs great, but is starting to show its age. 7 year old car...

Which leads me to ask. My cat is dying. I can smell it on rare occasions of spirited driving. If I get a test pipe and the motor fails, can mazda blame the engine failure on the test pipe and refuse to warranty the engine? If the cat stays, and the engine fails, can mazda refuse to warranty the engine because of failure to replace a dead cat.

Also, lately it burns a little more oil than usual. I searched the forums and all I could find were three causes. Either my oil injection system is spraying too much oil, the oil control ring is failing, or the engine's gone. I don't notice any loss of power, and the only code being shown is the Catalytic Converter below threshold. Now when I say it burns a little oil...it's only a little. On cold starts it'll burn a little, and is visible via the nice little cloud of smoke it makes. Small, thin cloud, dissapates quickly, and never gets bigger than the car itself. Engine idles smoothly, and cloud goes away once the engine reaches operating temps. It's more pronounced the colder the outside air temp. But the smell of oil stays even after warm up. I've owned the car since april, and it's only started doing this in the last month or two, and has progressively gotten slowly worse. Quite a slow progression, but noticeable. Now, could the failing cat be the cause of the excess oil burning? Or could a clogging cat merely be holding oil? Would a cheap Turbo XS cat delete possibly offer some relief at the cost of increased noise levels?

Also, been looking into the mazda remans as opposed to a rebuild, and it seems to be a mixed review there as well. Some say to just get the reman. Others say to have it rebuilt. But my research has me REALLY on the fence. If a mazda reman is hit or miss...is there a point at getting an engine installed that COULD potentially fail again in a year or less, only to have Mazda go "Oh Well"
My housing has almost 80k on it. Probably more when it eventually fails. (It's a rotary, It's not an IF, it's a WHEN). Seems general consensus is NOT to rebuild a housing with so high of mileage, but at engine failure...one tends to WANT the car back on the road. SO, it's rebuild or reman. Now, most are saying nobody rechromes these housings, and coatings aren't worth the money...so a high mileage housing is dead? I mean high mileage piston engine...bore 60 thousandths over and sleeve the cylinder...boom, reinvigorated engine...but the rotaries seem rather...finite on engine life. Very "disposable" engine design without a "disposable" cost. What are my options on making sure at engine failure, I get a GOOD, RELIABLE, engine that'll last another 80K.

And last but not least...the question that I can't seem to find an answer to. These supercharger builds have pictures and all, but finding a rotary engine beneath all the accessories is difficult...pointing out all the accessories attatched to the engine is as equally interesting as a "where's waldo" cartoon. Now, with that said I can't seem to figure out if the RX8 can be supercharged without loss of AC. which would delegate whether I go turbo or supercharged. I would like the smooth band of a SC, but since I live in a southern state...AC is a MUST, as I've measured cabin temps over 120*F during summer months in a piston car. God only knows how well the engine bay insulation will hold back the heat of a rotary.

Yours truly
KoiFry

RIWWP

iTrader: (2)

Maintenance: At @80k, I'd consider planning on replacing the radiator, coolant bottle, thermostat, and radiator lines in the next 10,000 miles.

Cat failure vs engine failure: It's possible that they might, but if you get a midpipe, keep the cat and put the cat back on when you take it for a compression test. However, you have an 8yr 80k warranty on the cat, so if it's failing, you should get that checked and replaced before 80k, not after. Sounds like that is rather soon.

Burning a little more oil than normal: How much are you actually burning? It varies quite a bit based on how much you drive. If you have to top off the oil every 500 miles or less, then yeah, something might be wrong. Otherwise don't worry about it. Completely stock is typically 1 quart ever 1,200 to 1,800 miles, 1,500 is about average. Someone who drives their car very easily could be up to 2,500 mile for a quart, and someone with increased OMP rates that drives spiritedly everywhere can drop it down to 700-800 miles for a quart.

Cloud of smoke: Are you sure it's oil smoke and not just condensation? If your cat is failing, your normal oil burn is going to be more apparent anyway. Not really something to worry about either way if it disappears fast or if it only happens with cold ambient temps. It's likely just the cat is 'catching' less oil than before.

Remans: If you want a reman with less of a worry about it randomly failing and Mazda leaving you out to dry, contact Mazmart.

Rebuild: The cost of remans is up, so rebuilds are more viable financially. New housings are pretty much a given at that age though. If you want a solid 80k engine, the only way to be sure is to have your engine, or another one, rebuilt by a reputable builder using as many new parts as possible. Can run you all over the place in price, but chances are it will cost more than a reman.

Superchargers and AC: I haven't seen any mention of AC delete on supercharger street builds. It should still be there. The main supercharger guys all live in hot climates, if that tells you anything.

CF_Koifry

Would a dual pass radiator be worth the investment? What about the oil coolers?

Didn't know mazda would replace the cat before 80k. Got a link to a service bulletin or something the keep my dealer from blowing smoke?


I'm probably not burning more than a quart every 1000 miles or so, and I'm kinda heavy footed. Not hard to imagine I could burn that much after your reply

Seems general consensus is to replace the cat...

[QUOTE} If you want a reman with less of a worry about it randomly failing and Mazda leaving you out to dry, contact Mazmart.

Rebuild: The cost of remans is up, so rebuilds are more viable financially. New housings are pretty much a given at that age though. If you want a solid 80k engine, the only way to be sure is to have your engine, or another one, rebuilt by a reputable builder using as many new parts as possible. Can run you all over the place in price, but chances are it will cost more than a reman.[/QUOTE]
YES!! GREAT INFO!

Seems like a supercharger may be the way to go then...they seem a little more forgiving than turbo as well...

RIWWP

iTrader: (2)

The stock setup is rather good overall, though if you want a radiator upgrade, get the BHR radiator. Most overheating engine failures are just from something failing in the cooling system, and given the cost of a new engine vs the cost of replacing all the cooling stuff with OEM (~$500-600 for everything from Mazmart), I advocate making the replacement of that stuff part of the maintenance around 90k.


epa.gov

It's a federally mandated warranty on all cars sold after 1996 in the US. 8yr 80,000 mile warranty on all major emissions components.


You are fine at a quart every 1k.

They both have hardware and reliability advantages and disadvantages. Both will have a notable decrease on engine life, since they both exploit the weakness of our side seal springs. More heat is the problem.

CF_Koifry

heat is a big problem, mainly due to the soaring EGT's causing deformation of the exhaust port, and chatter of the side seals against said deformation which results in decreased engine life (right?)

Now a richer tune could be counter intuitive correct? Inherently low compression engine, pushing unburned fuel into exhaust, causing temps hotter than a couple of 17 year olds on prom night. In a piston engine a richer fuel cools valves, reduces predetonation, blah blah. Is this true on a rotary? I mean is the average 30k engine life on a turbo renesis defacto? Or can a builder/tuner so things to improve the life? Aside from the obvious cooling upgrades that should be done for any reliable FI build?

RIWWP

iTrader: (2)

Correct about the cause.

Engine life while under forced induction is not set in stone. Just the general rule of thumb that more power = more heat, and more heat = shorter lifespan. A 280whp RX-8 will probably have a longer engine lifespan than a 340whp one, all else being equal.

Supercharging doesn't pack heat up against the engine the way turbocharging does, but that isn't immediately a solve-all. Yes, generally a richer tune helps to keep the EGTs down, same as a piston engine, but again, it isn't a solve-all. Yes, a proper tune will do wonders to extend the life of the engine ('tens of thousands of miles' vs just 'tens of miles'), but you shouldn't go into it with a mind set expecting X mileage from the engine.

CF_Koifry

...dude...

More than helpful at assisting me in my understanding of these furious little wonders. Still trying to bridge the knowlege gap of growing up with piston motors and going to a rotary engine. Anybody else cringe when somebody calls a Rotary a "motor"

I'm finding this site to be a wealth of info, and MOST of my questions I found through a search. Good to know the community will help those who try to help themselves first!

-Koifry