MagnusRacing

iTrader: (2)

Glad the info was of use!

RockLobster

I dont mean to play devil's advocate but....in my experience there is a huge difference between the racing reliability of the renisis and the early peripheral exhaust port 13Bs. We have raced on one stock port S5 engine in my FC racecar for 6 years now. Min 5 weekends per year usually more like 8-10. Car still makes 180 to the rear wheels, same as it did after break in 6 years ago. Never a hint of issues. I did blow up a motor prior to that due to massive over heating but a STARK contrast to trying to make a reni reliable for racing...which the teams i've worked with always struggled with...

TeamRX8

iTrader: (25)

Road racing a Renesis catless, I wouldn't run less than 2 oz. and probably closer to 3 oz. In an earlier post I had said Star Mazda was running spec pre-mixed fuel @ 1 oz, but I don't know why I said that unless I was thinking of something else. I never knew what the Star spec oil ratio was. People run 1/2 oz plus the MOP with a cat on the street RX8, so 1 oz per gal and no MOP can't be much more than that.

The problem with an OE build is you have no way of knowing what you're getting as compared to the detail of a quality hand-built motor, which depending on who built it you might not be so sure anyway. I don't think the top Star racers would run an unopened OE motor unless they had no other choice. Most of them are using hand built engines.



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Wraith Zero

I just did the same swap on my s1 except I got an automatic s2 engine for a good deal and placed it in s1 manual car. I used s1 lower intake and injectors with s2 upper intake. S2 e shaft sensor is the same, s2 upper intake sensors and throttle body plug into s1 electronics. I left the omp stuff on the engine and placed the s1 omp beside my washer spray nozzle. No need in deleting the omp system and capping of the feed scource.

blu3dragon

iTrader: (1)

I guess that works too.

Dumb question; You are still premixing right? (since I assume that S2 omp is not going to be working without the ECU driving it).

Wraith Zero

Yeah I'm premixing, got 500 miles on the car now. Also the omp system fails open. Pressured oil was going into the intake right at the vacuum point below the oil filler. I ended up blocking the oil feed on the front of the engine

blu3dragon

iTrader: (1)

So now up to 27 days, 20k miles and approx 74 track hours on my pineapple rebuild.
14 days, 5k miles and approx 51 hours with no OMP and premixed fuel only.

Still starts good every time.
Does seem like I am down on power now though. Suffering from a misfire code that only happens occasionally on track. Have suspected that as the reason I'm down on power, but after going through all the normal reasons for a misfire I'm now wondering if it might be caused by low compression on one rotor face

askannav2094

Thanks for the Series 2 , post. Question, based on this information is it possible to use just the series 2 core in a Series 1 build.

Thus removing everything Series 2 related including the OMP system & replace everything from the series 1?

Here in Australia, Series 2 motors seem to out number series 1 motors in wrecking yards & are offered at lower prices !!!!

@italia916

blu3dragon

iTrader: (1)

As far as I know, and recall, you can use all the accessories from the series 1, apart from the OMP pump, since it doesn't have the mechanical attachment to drive it (series 2 is electric).
So, you just need the core from a series 2. But, you will have to premix all your gas with it, which is a pain for a street driven car. I'm also not sure how well it will hold up to street use with no oil injection. Honestly, for street use, I would rebuild the s1 core... That way you know it will be good for some time and avoid the whole premix mess. Even an s2 core, if it is used, might already be down on compression.

My track build is still working well (aside from the unexplainable misfire code which I am now simply ignoring), but in my case I started with a known good s2 core.

blu3dragon

iTrader: (1)

Hi Magnus, what were the symptoms of your oil seal failure?
I suspect that I have that issue now...

TeamRX8

iTrader: (25)

He hasn’t posted in this thread for over 2.5 years and hasn’t been on the forum for over a year.

@italia916

Just answering some questions regarding 100% premix and street driven use on a series 2 (I guess it applies to series 1s too), but I had decided to ditch my 100% series 2 swap into series 1 build (entire car - mechanical and electronics) in favor of just buying a working series 2 car (2010 R3 with 131k miles on numbers matching engine - carfax seems to line up with mileage). I’ve noticed oil usage degrade to virtually zero over the last 14,000 miles I’ve driven since August 2018 which I’m sure either the lines are clogged or 1 or both OMPs failed and, as a counter measure, I upped my premix ratio to 1.0 Oz per gallon from the 0.5 Oz per gallon I’ve used since buying. I know it’s not much to go off of, but so far the car still starts on a dime hot and cold and runs like a champ with zero issues. I’m thinking of keeping this engine in to see how far it can go as is as it’s my primary daily and I have an 18,887K mile engine ready to go if/when this one decides to poop itself.

*Also something to mention is that running 100% premix isn’t bad at all for a street driven car. I actually prefer it which is why I removed the OMP from my SA22C which was perfectly good, but line was clogged and the block off plate was cheaper than a new line. I think I just like knowing my engine is getting all of the lubrication it needs vs depending on OMP(s) that may or may not be working 100%

Brettus

iTrader: (2)

The oil usage probably dropped off due to the amount of premix you use. I've found that heavy premixing with no OMP on a street car results in the oil level actually rising over time.

@italia916

fuel and oil systems are 100% separate and never mix. If that were the case the last 3 simultaneous oil analysis I’ve had done would’ve shown fuel mixed with it. Premixing will never cause your oil level to rise

MagnusRacing

iTrader: (2)

Still kinda here lurking... have been taking a break from the racing the past few years. Anyone want to buy an RX8 race car with a bad motor???

Are far as the oil seal failure it will be very apparent with white exhaust smoke and fouled plugs... can still run through. I did Nationals at Laguna Seca with a bad seal.

Brettus

iTrader: (2)

Except ....when it does ! Hard to get your head around ...I wouldn't have believed it unless I saw it with my own eyes either.
Any fuel will evaporate off unless the engine never gets hot for any length of time. The premix oil however , will stay there.

You are not the first person to report low omp oil usage when using premix

TeamRX8

iTrader: (25)

Well my point was that if someone hasn’t been around in a while then sending an email or pm might be more advantageous than bumping an old thread noob-style

blu3dragon

iTrader: (1)

EDIT: Apologies for the long and mostly OT post. I guess I could have started a new thread on my mis-fire issue. The relevant part for this thread is that I have run for ~67 hours on track with no OMP and pre-mix only, and compression still seems good :-)

=====
Thanks for the replies :-)

My engine seems to smoke a little bit continually, and then produces James Bond style smoke screens while misfiring 2-3 times per lap once I get on it. Keeping revs down seems to help with avoiding the smoke screens, but it will still hesitate and miss. Had to cut my last weekend at Laguna Seca short as I was making no power while it did this and getting a meatball flag to come in. Was basically un-driveable on track, although it drives fine at low rpm

Coinciding with the bad misfires (creating smoke) I also seem to get evap leak codes (P0442 and P0455). I'm not sure if that is co-incidental or not. Maybe the same vacuum that is sucking oil in is causing the evap leak codes? Last time out I also got an Intake runner stuck open code (P2004). Never seen that one before.

Thinking about the behavior, I have a suspicion that it sucks oil in at high rpm when the throttle is closed (i.e. under strong vacuum), but I'll need to drive it more to be sure of that. The reason I say this is that it seems to rev out in 2nd gear fine. But after shifting to 3rd, or after braking from high rpm and then getting back on the gas, it misfires and smokes. The oil level also drops noticeably after it does this (0.5-1qt after 15 min of trying to drive on track).

I also get smoke on start up after letting it sit for a while, or after driving hard. (driving at low rpm and not letting it sit doesn't produce smoke that is noticeable from the drivers seat).

I'm going to try a de-carb to see if that frees anything up, but otherwise looks like it may be engine out time.

~4 years, 90 track hours and 23k miles on this rebuild. OMP system was deleted at 23 hours and 14k miles and run with 100:1 premix as a dedicated track car since then.
Very occasional misfire (only on track) started at 33 hours and 17k miles. Did all the normal stuff to try and resolve that and then just lived with it. Progressed to the current state over the last 2 track days (~3hrs), although it had occasionally missed and blown smoke in the past, most of the misfires were not noticeable beyond the flashing CEL.

Compression still seems good in that it starts up with no issues. Very occasionally I'll get a long crank after turning it off for ~5 min (typically while filling up with gas). It has an s2 starter and I have not measured the compression though.

TeamRX8

iTrader: (25)

Is your pvc line from the oil fill/sump connected directly to the intake like OE or into a catch can? Any oil coming out there?

blu3dragon

iTrader: (1)

It's currently connected to the intake. I did remove and check while the car was standing still and did not get excess pressure or oil when revving it, but I will run this into a catch can and drive it under load to see what happens...

TeamRX8

iTrader: (25)

You should be able to tell if any oil is coming out. There will be residue inside the bellows/preTB area if anything is blowing up from the oil sump. A good engine will be bone dry there. If you need a catch can then it’s only because you need a new engine.

blu3dragon

iTrader: (1)

Well there is oil coming out. Lots of it... I installed a catch can, and although it was vented a little, it wasn't vented enough to stop my dipstick from blowing out.

Tried a water de-carb, but I'm not sure it was very successful. I sucked about a gallon through in total, but it went in slowly and I didn't get any steam out of the tailpipes (although it was enough to make it miss and pop quite dramatically).

After that, took a ~15 min drive in which I revved it up in 3rd and let it coast down 3-4 times. This was enough to collect a quart of oil, blow out the dipstick and deposit at least half a quart in my engine bay.

Basically at high rpm it is blowing oil out at quite a rate. Keep the revs low, with not much vacuum, and it doesn't seem to have any problem.

It seems after a little over 90 track hours this engine is toast :-(

TeamRX8

iTrader: (25)

Soravia

Why did they engine blow? No ONP? Or did the carbon build up in exhaust cause it?