"slightly" lighter & snap ring to hold it in place might not be all that important

the fully balanced set is, cuz each rotor will weight slightly different, even if it has the same letter stamp, same thing for F&R weight.

like I said earlier the RB set is not that expensive if you count the price of a pair of brand new rotor & brand new f&r weight/counter weight.

Most MSP parts (or should I say ALL MSP parts) are much better than their older siblings, at least metallurgy wise its already a giant leap forward ... slightly better geometry, slightly lighter e-shaft (0.6 lbs, but its kinda useless), etc.

but sadly a lot of 13B's fundamental short comings are "still" here.

Not to mention the biggest difference between MSP and all prior Rotary is the exhaust port. This is one of the "biggest" issue to make serious power.

sure it did cut HC down by around 50%, it lowered the ultra loud exhaust noise so it can use less restrictive muffling material (Read : CHEAPER), improved the MPG by a tiny bit.

but if the exhaust stream has to take a 90 degree turn ... that will be (and its still is) a problem, the slower it exit, the less power you make.

ported exhaust port should be able to help this problem a bit. We just have to wait and see.

 

and that is one reason i am choosing to stay at the mentioned power level and a redline of 8.2K FIRM.
OD

 

you don't need the RB set then.

just re-use the stuff you have right now, take your engine apart, clean it nicely, then send it off to balance : rotors, f&r weight & FW & PP.

couple hundred bux should do.

or just let someone to handle the build & test work for you. a lot of people can do that + balancing.

 

If you have a front iron handy , check how much meat there is around the dowell. I've had 2 fail at the point that obviously looks the weakest .One of the Petit guys had the same and Pretty sure there have been others as well . I don't think a full dowelling or stud job is necessary at this power level but I would definately look at strengthening that one spot . Have some ideas but have not had a chance to try them as yet .



Blowby into my catchcan on stock side seals has always been negligable . I guess if you have it apart then why not ?

 

The only two failure modes I've seen so far could both be made less likely to fail IMO

Apex seals - well we've had that argument and there is no real proof one way or the other . But at least I feel better with bendy seals in .
Dowel land - as above

 

I've never had nor seen a dowel land fail for any of the above mentioned scenarios.
Breaking a dowel or tension bolt land is a result of improper torque or overheating.
The amount of engine torque output needed to break this is beyond the contemporary examples.

 

The first one broke due to misfires at the track - the whole car bucked .
The second was a bit of a mystery - we 'relieved the dowell hole' on advice from a forum member and it broke the very first time i accelerated hard . - no misfire knock or any other calamity .
And like I said - i'm not the only one .

 

Well, think about what that dowel and it's mounting points do and you will understand why, under normal conditions, it is pretty much indestructible.

Relieving the hole was a pretty big mistake, BTW.

 

Well ................. thanks for that Captain Obvious

Maybe it is , under ............."normal conditions " .

I was told it was a common occurance in older high power rotaries and there was this neat little trick some of the drag racing fraternity did to help prevent it . Knowing they knew more than I did , I went for it .

 

subbed. Thanks OD, you have been asking some great questions lately.

 

Jackson, there is a HUGE difference between yapping on the internet about all the parts you think are "cool" and necessary and giving people solid advice which is oriented toward their particular needs and reasonable budget. Once you start charging people money for your advice/labor and taking responsibility for the outcomes of your opinions, you will see what I mean.

I am glad you finally read OD's inquiry enough to realize what HE needed........

 

appreciate all the insight.
I was a little surprised no one mentioned lower compression rotors?

What MM has said is also very true. The engines peripherals are not to be ignored. But for this thread I was only focusing on the internals. It is reality other things that influence engine life epectancy are not consistantly perfect, temp spikes, slight fuel pressure changes, spark plug fouling, wire going bad, etc all can happen unexpectately even with race maintainence.

 

OD's original post he never talked about his budget all he ask was how to make it more reliable. so I just told him about all the good stuff.

 

if you use older style rotors you have to use the deeper apex seals. and its not going to be cheap.

 

Everybody has a budget and his has always been helped by his self-imposed redline of 8200 RPMs, about which he has posted for well over a year.

 

Several threads have already been posted about it and the opinions have not changed.

 

oh--understand--just found it interesting that no one mentioned this as a option for a more stout FI build.

 

Subscribed, are there any major internal differences to the series 2 core that would make it a better candidate for a FI build? I will be buying a second engine core to build for FI in the future and have heard the S2 Renesis have a significantly reduced failure rate?

 

The engines are pretty much identical, the only differences are related to the oil system and number of housing nipples to inject oil. Since there are no cheap tuning solution for s2 engines just get an s1 and... premix. If you're not dumb there's no need to have an electric oil metering pump etc
Build an engine with fresh parts, good clearances\tolerances and you should be good to go unless your goal is a wild monster with a 20hrs engine life expectancy.

 

bse--afraid pre mix alone has been shown to not do the job with the renesis engine. Meyer racing--who has more hrs of data logging EVERTHING concerning this engine than anyone that I know off, has shown that without the omp the corner/side seals give it up much sooner. I have known Eric for a few years and he is **** about data collection and diagnosis's. He struggled for some time with why his fresh engines were losing power so soon. The omp lubricates the corner/side seals in a way that pre mix cant and this allows those areas to run cooler than with premix alone. Premix with the omp is the way to go with this one.
I am thinking--dont know for sure but the s2 model may not need pre mix.
The internal oil passages for the S2 are also different. If the s2 engine could be tuned-- i would go with one in a heartbeat.

 

You are right, seal chattering without oil injection is a documented issue in some cases. However i thought that we assumed the engine in it's entirety while discussing s1\s2 engines, that's why i said that an s1 unit would be enough
I am against the OMP removal as well, sorry if i was not explicative enough in my previous post Denny!

 

Where premix alone fails is at high RPM and off throttle. No fuel = no oil but at 8-9K rpm u need oil.

 

Off throttle you don't need injected oil There is no load.
Even the OMP mostly shuts off at that point.

 

Hmmm - my premix strategy for last 2 yrs looks good going by that IE 1/2 omp + premix at 200:1