Looks like I won't get a chance to try the new engine management system very soon. Whilst cruising around last week, not driving hard at all, the engine started sputtering & coughing.

No compression in one of the rotors. Gee, what do you think THAT means?




I guess the good news is I'm going to rebuild the engine with 3mm Apex seals vs the stock 2mm ones. Also, budget permitting, I am going to beef up the oil system, add larger injectors, and do a mild street port.

I'm trying to remember why I bought this car instead of a used M3. Someone please remind me. Please!

 

because it was a used M3?
lol - good luck on the porting

 

Sucks about the engine. Was your turbo system operating properly?

I wasn't aware 3mm seals were yet available for the Renesis.

 

^^^Don't know how easy they are to get otherwise, but I know MazdaMotorsports sells both 2mm and 3mm ceramic seals for the Renesis; can't remember if they sold 3mm non-ceramic ones.

 

3mm seals will require that someone machine out the rotors. It can be done but I haven't seen any one do it. 3mm seals aren't a better option than the 2mm seals. In fact that's backwards. The heavier seals such as 3mm have more of a tendancy to "float" at higher rpm's and seal worse. They also wear the housings out faster than the 2mm seals. I've seen 600+ hp RX-7's using stock Mazda 2mm seals. There really isn't a need for more. If you aren't going to use very expensive Ianetti ceramic seals (which aren't available for the Renesis yet anyways), stick to the stock ones. I'm not a fan of any of the other aftermarket seals not even the other ceramic ones out there.

There are a couple of things that can be done to the oil system internally on the motor to increase oil flow. These include porting the front cover under the oil pump, modifying the oil pickup tube, and changing the oil jets in the eccentric shaft. Upgrading the oil coolers and adding ducting is a nice option too.

As for porting it there is alot that can be done to the exhaust ports and it isn't making them larger. I disagree with the way that the only ported Renesis I have seen ported to date was done. I'd do the exhaust entirely different. It is a very bad idea to cut into the water passages and then weld them up. It is also unneccesary. There's a better way to do it. I'd also do the intake a little different but you can't do much there anyways and get anything useful out of it.

There is no need to go with larger injectors. Not until you pass 300 hp. If you've got a turbo i can see your desire to have them there. If this is still n/a, don't worry about it.

 

^ spot on.

i disagree with it being a bad idea cutting through the water jackt and re-welding, but that's personal preference at this point.

fred is right on with not making the ports very much larger, though. they're big enough. radiused edges and close attention to the turning points in the exhaust is what's going to build the power with these.

the intake needs very little work. primaries can be closed pretty late without losing any low-end power. backfilling and helping with the entry angle will help with that.

good luck, take pictures

 

This is the guy who had ProStreet install a Greddy turbo and found they botched the install. He managed to sort everything out himself but it looks like there was something that wasn't quite right. Glad to hear Rick's Rotary will be doing the work and look forward to his analysis.
________
Milf Russian

 

Gonna have to go and disagree with you there, RG. MazdaMotorsports sells Ianetti 2mm seals for the Renesis.

 

Wow man, that sucks. Can anyone speculate as to what happened to his engine. He claims he wasn't even under heavy load. This is similar to what broke_apex_seal said happned to him. This really has me concerned, as I'm sure its directly related to the turbo.

 

I think 3mm seals for any engine running under 400whp is going to be overkill and unnecessary. There were several folks at Sevenstock (Rob Goldman, Rick Engman) who spoke to the quality and durability of the stock 2mm seals, the issue people have is bad or improper tuning.

I'm sure if you rebuild the engine properly with stock seals and get a good engine management system you'll be able to run your turbo safely. MazSports unit should work nicely for you, I'm just sorry about your engine.

 

That really sucks but you seem to be taking it better than I would. Couple of questions:
1. Were you running the original Greddy mapping?
2. Did you have the stock cat?
3. Did you have a wideband O2 installed?

 

Are you sure they aren't just mislabeled and ssumed to be the same as the older ones? Last month at Sevenstock even Paul from Mazmart and Rick Engman didn't think that Ianetti had those seals ready yet. They said he was working on them though. He could have them though.

Dave, I'm just not a fan of cutting into the water jacket. It's completely unneccesary and isn't gaining anything. I have seen alot of your other work and think you do know what you are doing and are good at it. I just disagree with the water jacket issue. I may find out on my own Renesis soon enough but I'm not cutting into the water jacket.

I see the need for larger injectors now. You don't need to go too crazy though. It sucks this happened.

 

i like how rob explains the 2mm vs. 3mm debate. http://pineappleracing.com/TechLinks.html

my personal opinion is go to 3mm seals if you've got nice machine work/lightening done to your rotors, but the apex seal grooves are out of spec... not worth the money doing it to otherwise good rotors.

fred, you know i always respect your opinion.. i don't regret doing it since we haven't had any problems, but in the future, i'll be taking your advice and not going that deep--as i haven't seen the gains from it... although, we haven't had the means to maximise the setup yet, so all things in time.

 

No, I'm not sure. Just something I saw on the Mazda site. I'd like to think you could give a website officially linked to Mazda the benefit of the doubt that they wouldn't sell you something not made for your car. But then again, benefit of the doubt can be a dangerous thing.

 

If they aren't available yet they will be soon anyways.

 

E36 M3s had problems with lack of lubrication while hard cornering. the oil in the pan would shift so much that the oil pickup wasn't able to do its job. valves would tap and such...BMWs aren't really that great of cars. i personally would never buy one.

 

Rick @ Rick's Rotary had a look at my engine.

Total catastrophic failure of the apex seals for the front rotor. His guess is that there was a stress crack already, and it just gave out & tore everything up.

Since the car WAS overboosting during my misadventures with ProStreet, pox be upon them, that was probably when the damage occurred.

I was using the GREddy map from GReddy. Like I said before, I don't run this car hard, and when the failure occurred, I was driving on city streets like grown ups do; not getting my foot in it at all.

 

My, how I do hate the words "catastrophic failure of [anything]." Guess it makes sense considering my line of work. Oh, and who says grownups don't get their foot in it?

 

Nuthin' wrong with getting your foot in it, just not on an urban street with lots of pedestrians & traffic.

 

Mazda Motorsports has had 2mm Ianetti ceramic apex seals for quite a while, they're about $2k for the complete renesis set, there are two options, single piece and two piece, the one piece are $100/rotor cheaper

edit: checked inventory, shows zero 2-pc in stock and only enough 1-pc seals in stock to do one complete renesis engine

 

did you own and race one? I did, don't quit your day job ...


.

 

Hopefully some of these more recent blown engine threads are teaching everyone on the board to take their cars to the reputable rotary shops for tuning and not just going to any local place that says, "sure we can tune a rotary, why not..."

(nothing aimed at you personally, Sapphonica)

 

No offense taken. ProStreet sure LOOKS reputable (www.prostreetonline.com). I've since found out that they USED TO BE a top-notch shop, but the good people left & started their own gig.

In other posts, I've listed many, many the things they screwed up on my install. Never again!!!

 

^^^
Cool. I actually blew the engine in one of my 7's for taking it to a shop that said they knew how to tune rotarys. And as you said, "Never Again!!!" But damn did I also learn the hard way. (The shop in question is no longer in business, so I feel it not relevant to list them, and it was several years ago.)

 

i would look for petitt or gotham, steve kan is pretty amazing with a 2 rotor IIRC