MazdaManiac

iTrader: (3)

dannobre

iTrader: (3)

WOW

Here we go again..into drivel land

So who's going to build some Inconel or wonder-metal side seals (at a price that approaches something us mere mortals can afford)

Brettus

iTrader: (2)

Do us mere mortals, who don't race in competition, really need better side seals ?

MazdaManiac

iTrader: (3)

I presume you meant springs, not the seals themselves.

Making them is not the issue. Finding the resources to test them can be a bit daunting and out-of-synch with the second part of your request.

Even at twice the price of OE springs (which retail at about $6 each), we would need to sell hundreds of them just to break even.
As notoriously cheap as rotary motor builders (and owners) are, it is unlikely that 20 or 30 motors-worth of the things would go out the door in a timely fashion.
And the people that really need such a spring - like Eric - are not allowed to use them.
So...

I rest my case...

dannobre

iTrader: (3)

Dunno...I have some engines to pull apart to see why they failed .

( as soon as I can walk anyway )

Springs LOL.....gotta love pain killers

Highway8

iTrader: (11)

12 side seals per motor, right. OEM retail = $72. If they are double the cost = $144. I plan on building 2 motors in the next year. I will pre order 2 sets right now and pay double if that helps the cause. Cheaper and more economical to spend the extra money up front then to rebuild the motor latter. HAHA Cheaper and Economical, you never here those two words spoken in a positive way about a rotary.

In regards to Race Rules that prohibit Eric and other Grand Am teams From using them: I have no experiance and dont know how these things work so maybe I am just be practical, but because the item does not increase engine output and would only increase the amount of races he could run before rebuilding the motor, he should be able to petition for a rule exception/change. A race series would have to be pretty stupid to say he can not run different side seal springs.

PhillipM

I've got an old engine here with a cracked side seal, if I get around to rebuilding it I'll have some inconel springs made and see how they fair, not going to give much evidence without a control engine running stock springs but given it's suffered one problem already...

EricMeyer

Who has first hand knowledge of using two side seal springs? First hand knowledge. I spoke with an engine builder who did this and took off some material from the bottom side of the side seal and his customer said the thing was crazy strong. He also told me it didn't last very long. This was a Renesis motor.

Like Brian offered before and I have agreed with some other smart engine builders, the common belief with the smart crowd of builders who look at Renesis RACE engines is that the spring is hte weak link. She doesn't like heat. Regardless of side seal clearances, she doesn't like the heat. When we fatten the heck out of our tune we still turn around 216'ish and 150 with much, much, much lower EGT's than running it at .93. About 150F less. We also run some conservative timing (Thanks Brian for your advice) to be careful to locate the combustion event from what we believe to be away from the export port location. The theory hear is to try and not have the combustion event RIGHT AT the side seal groove. Impossible to measure but that's what we're trying to do.

Can we all agree that spring wear is rarely seen in street engines and is mostly isolated to race engines? Don't know diddly about street run motors.

Meyer out

MazdaManiac

iTrader: (3)

I've played with those clearances. The problem is you aren't "strengthening" the spring by doing this, you are just limiting its travel.

"Conservative" timing will do exactly the opposite of this.
Flame speed is flame speed. It is controlled by lambda and, to some degree, gross compression.
If you are trying to "keep the heat off" of the exhaust port and, conversely, the side seal at that point, conservative timing will not do the trick. it will just accelerate the flame front and cause the trailing edge of the combustion event to occur at the port.
The difficulty here is exacerbated by the fact that net EGT will not necessarily show you at which side of the "window" your spark event is occurring.

olddragger

iTrader: (3)

yep. Needs to richen the lambda?
Rules can be changed like the Star racers can now use ceramic apex seals.

Ok--let me throw something else out (since I mention the possible side seal composition problem).
What effect does the exhaust sleeves have on the actual exhaust port temperture? Could these sleeves be recruited to help with port cooling?
Here is my line of crazy thought. The exhaust sleeves do not complely touch the wall of the side plate. There is a dead air space present. This is the space that the oem air pump uses to help light off the cat on cold starts etc. Once that system is removed then its dead air and about a 1/8 inch space? It also collects carbon/soot which can further insulate the sleeves from any cooling the water jackets are trying to do.
Would it be possible (and I think it can) to utilize that dead air space? Use the imagination here?
My gut feeling is that the sleeves are contributing to high exhaust port temps.
I know that in oem config the engine coolant only collects approx 10 degrees as it passes all the exhaust ports.
OD

EricMeyer

Let me try that one again----on decel with fuel cut and timing. Tuning while watching EGT's on transient off throttle allowed us to really dial in timing and fuel mix and lower EGT's. Bottom line is our objective to lower heat was accomplished.

PhillipM

^^Glad to see I'm not the only one using the decel fuel transients to cool the engine down then, it's surprising how much difference it makes tbh!

EricMeyer

Totally!!!!

BDC

I tried double side seal springs on an older 13B. Within 100 miles of driving the first two days after build, every single one of them were broken into pieces and left me with ground down side seals. I also barely got the car up the driveway it had such **** poor compression.

I am apprehensive to suggest anyone to try it on this engine because I believe it will produce the same detrimental effect. I'd rather look into having a better spring made that can withstand the heat. That's all that's going on on this engine.

B

Highway8

iTrader: (11)

I have already said I will buy 2 engine sets at $25 a spring if someone comes out with an improved side seal spring.

Brettus

iTrader: (2)

cam you be more specific ?
So you are adding fuel on decel ?

TeamRX8

iTrader: (25)

Material type alone won't cut it. First and foremost it has to be a spring ....

WTBRotary!

iTrader: (6)

Yes yes thats what I was wondering too...

Sounds like a good idea if your engine is really hot...

Do you think the Cobb AP could turn this "feature" or whatever you want to call it on at say 220F to help cool the engine off more?

EricMeyer

Can't speak to the Cobb system--perhaps someone could comment. Our system does this for startup until water temps gets to a predetermined point. We run a lean startup to avoid fouling plugs and then she goes to a richer mix.

It has been my experience that the more the engine gets heat soaked (lets say 220 oil or god forbid, water), the harder it is to cool. My personal experience is that the root of this issue comes from inadequate oil and water cooling. This inadequate cooling gets into a run-a-way mode and that's the thing your trying to manage. Kinda like going on a vacation with your home A/C off and then coming home to an upstairs temp of 85F+ You arrive back home, turn on our A/C and it takes a while to back back to 71 or whatever you set it at. The problem is not the A/C unit being too weak---the problem is that the heat got the home too hot for the A/C to process quickly. I've looked at high oil temps and have found no coorelation to decel fuel cut and timing to influencing oil temps. We are looking at EGT and we reduced our EGTs by over 100F when addressing this. It has been my experience that these engines (back to the side seal springs) don't like it above 1,600F egt. A few other engine guys I've talked to that have access to EGT data and engine teardown efforts agree. It is 1,600F exactly? Dunno. I do know that when we leaned her out and ran 1,700F we wasted side seal springs faster. Our current richy rich tune peaks about 1,500-1,525 depending on track. Measuring the exterior exhaust manifold temperature with an infrared handheld won't tell you this just like pointing it at the pre-throttle body exterior air intake and comparing it to the actual air temp. The actual air temp is pretty much close to ambient or just a bit more. The exterior intake tubes will be waaayyy higher. Insulated your air intake will help but it's not gigantic temp reductions for our engines and I suspect stock engines/stock RX-8 passenger cars as well.

My gut says the engine in your statement above is heat soaked like the hot upstairs analogy. Back to the big radiator discussion posts all ducted up so air HAS to flow through it---same for oil coolers. Removing the black plastic inner fender well liners will also support better air flow and do a much better job and cooling the oil when the car is moving. This WILL throw some debris on the backside of the oil coolers and making some small dents in the cooling fins (and something that some people will freak out over) but this is easy to do for a track weekend and them re-install them for everyday driving when you return home. Another thing you can do is run a different air box that allows the air to more easily flow through the radiator. The stock big black plastic box is like putting your hand on the back side of a small square fan that some people put in their college dorm room windows. Your hand will be a restriction and you can hear this as an audible change in said fan. Something that is smaller like a tube based allows the air to flow better through the radiator. If you want to go the extra, extra mile, look at the stock radiator fan---it has a crrrrrraaaap load of horizontal plastic surface area and that blocks air flow!!! Get an after market fan.

Here is a gross example of this. Look at the small frame (or really the lack of). AT SPEED, this allows for air to rock and roll right through the radiator and right through/past the fan. For us racers who run AT SPEED, this allows for much better, less restrictive air flow than the second picture link below and the radiator will perform its intended function better.

1st Pic: http://www.google.com/imgres?imgurl=...w=1378&bih=699

Compare and contrast: Note the black plastic material that parallels the radiator surface.

2nd pic: http://www.google.com/imgres?imgurl=...w=1378&bih=699

You can see which one flows better AT SPEED. This second pic pulls air better at a stop light. The first pic is used in racing applications and the second in passenger cars (for traffic obviously).

On the dyno we run our cars oil about 210-215 because that is the high side of what we see on the track therefore it is mimicking near actual race parameters---same for the drivetrain all nice and warm and juicy. This is for recording power and for tuning. When we are done with our dyno pulls we just let the bigger spal race fan run (just like in the fan in the first pic) and water gets back to a lower 185 water (thermostat temp) and the oil will zip down to 150F'ish. This is like a cool down lap at a Club weekend track event---you arrive back at your parking spot and don't have to keep your engine or ignition on to keep the fan on to cool the car. If you keep just the ignition key turned on it is doing pretty much nothing because the water isn't circulating in the engine---sort of like running your home A/C but not the fan to push the cool air through your hot home.

Moral: decel tuning to lower your oil is really, really, really tiny. Work on keeping the temps from getting out of control in the first place.

rx 8speciale

iTrader: (3)

so much learning in this last 2 weeks , this is awesome baby!! good job Eric
thanks for sharing!!

olddragger

iTrader: (3)

wisely said.
I would like to add that the oem fans supports can be thinned out they do not need that much support. I took a dremel and removed 2 supports from each fan to open it more--just like Eric points out. Small help, but help none the less.
One thing that differs greaty between us and the guys that are Racing is we have to live with that air conditiner condenser right in front of the radiator. That thing blocks a tremendous amount of air flow at lower speeds. You really need a substancial delta pressure between the anterior and posterior sides of the rad to have any flow at all. That is the reason a small secondary radiator works well for the street.
If we could get a condensor relocation kit from someone that would be a HUGE help at low speeds--or better fans and control if we cant.
I think I would like an emergency overide fan switch in the cabin. For example, you get stuck in traffic and you see you will be moving very slowly for some time, its really hot outside and you see the temps climbing. Rather than having to play catch up later, like Eric said, I would like to be able to ingauge the fans to prevent that heat soak from occuring in the first place.
I may work on this--add to list?

So Eric the exhaust temps are more influenced by the chemical reactions going on rather than the lack of the port not being cool enough? That makes sense.
Wouldnt synthetic oil be off a small help in that area? Are you running the Shawn adaptor?
If I remember correctly you aren't?

Highway8

iTrader: (11)

While I am swapping motors I sent my spair LIM to Brian at BDC to have him ceramic coat it. He is going to evaluate it for some port/polishing too, but the main thing is ceramic coating. I am also goin to place a heat shield between the header and the LIM. My intake tube is also going to get ceramic coated or wrapped. I do not expect any large gains from any one thing, but its the little things that can help.

Cooling: I have my own unique issues and custom solutions due to the large front mount intercooler. At the moment one of my solutions is to cut down the size of the intercooler to allow for a second large fluidyne oil cooler. I am considering having both of them coated with a heat dissipation coating to increase the metal to air heat transfer. Companies claim anywhere from 25-45% increase. Plus it will give it a dark grey/black stealth look. LOL

Link to the product I am refering to http://www.nicindustries.com/heat_dissipation.php They claim it is proven to increase heat transfer by 35-40%

Eric, any experiance, opinion or information about heat dissipation coatings? Its only a few hundred dollars but if it works its money well spent. I would consider doing the same to my BHR radiator.

shadycrew31

iTrader: (6)

I thought the LIM was effected by the exhaust manifold as well. so I wrapped the exhaust manifold.

Then I discovered the LIM was really just soaking up the heat from the engine regardless.

After a short drive I can grab my exhaust manifold without being burnt, its slightly warm but not horrid. The LIM however is very hot I can barely touch it but its still not cool at all.

In terms of cooling that region of the engine I'd look into getting fresh air in there through a diverter or something similar, wrapping the exhaust manifold and letting the LIM breathe.

Don't suffocate it with a blanket or a heat shield, since its essentially soaking up the engine heat wrapping it or throwing a shield on it will only insulate that heat in there.

RotaryMachineRx

iTrader: (1)

^ It would be cool to funnel something up from where the air pump usually is, for those of us who have removed it, to help cool the LIM but then we would have to take into account the pressure changes that may occure inside the engine bay and how it could effect flow through the radiator/AC condenser/intercooler. I can't think off the top of my head considering its monday morning but the Engine bay is usually lower pressure than the surroundings at speed right??

EricMeyer

Never heard of anybody using that stuff. I would save your money and buy a huge radiator and big azz oil coolers and support them with custom ducts. The hot ticket is to have individual front ducts for each system: One for water and one for intercooler. Putting an intercooler in front of the radiator is on the same theme of the A/C condensor as Denny refers to above. The NASCAR guys will have center mounted radiator ducts specifically for rad and then a specific oil cooler duct for the oil. They each have their own intake and each their own exhaust.

There are going to be some book reading aero guys that are going to argue with this next comment and theorhetically they are correct but for all practical purposes you'll never see or can measure this next issue: Ducting the intercooler spent air UNDER the car. Yeah, yeah downforce blah, blah. The fact of the matter is these are stupid street cars. Air is already going under there and we don't produce any negative lift to matter anyways. It is more important in these "air cooling/heat discharge" applications to do just that----not worry about downforce. You big turbo guys want that cool air/lack of hot air and ducting from the wide center opening and then down and out the bottom of the car can do this. You'll need to find a local fabricator. I would suggest a roundy-round late model guy who builds cars for this market. They do this jazz alllll the time. Cheap sheet metal. You can also build a much better setup for your water radiator (which I would upgrade big time). We use a dual horizontal pass C&R radiator we had custom designed and the path that the hot water travels across the radiator and then across back to the same side is more than 2x than a typically vertical drop from the top to the bottom. Think about that for a second---exposure of this hot water to air flow from a longer period of time. We can run our car all day in heat in the draft at under 190F. At some tracks we have to tape up the front opening because we are running on the 185F thermostat---too much cooling! Add to this custom larger oil coolers and you have now really cooled the engine. More importantly you have used a better water radiator to allow for the new obstructive---the intercooler, to grab more air. Essentially you make a better, more effective water radiator that is not hampered by a big intercooler and then make a more effective intercooler as well. The oil coolers come into play because they are symbiotic----lowering oil temps helps take water temps with them. Therefore, larger more effective oil coolers help your radiator that now has less frontal air because it has a big nasty intercooler in front of it. Make sense?

Now compare and contrast this to coating stock oil coolers and stock radiators with technology that I've never heard results about. Maybe this stuff is the cats meow---have to look for customers using it. I have yet to see oil cooler manufacturers use it nor radiator manufacturers. Why? Perhaps it doesn't really work. Dunno.

A side note: If your spending all this money on the LIM and coatings and such, I would hope that you've started with a new, fresh, professionally built motor which takes advantage of the various tweaks and such. A rotating balanced assembly is a no brainer. Higher oil pressure regulator is a no brainer. The better oil jets, new or better water pump. New rotor and stat bearings. All new seals. New oil control rings. New oil pump and chain. I would go as far as new oil pump delivery lines to the cad coated oil squirters or replace them too. Brian can do all of this and I have confidence he will do a fantastic job and these upgrades and parts are a one-time deal. He offers great customer service and always seems to call me on the weekend when I'm on the boat with my best girl and bug me....eh, er, wants to talk shop. Great guy. He balances all our stuff and has become a great source for technology talk. He could easily tap your front and rear housings to accept a larger -10 oil lines to run to your new larger oil coolers. He can also doctor those housings with a grinder to get more air in and out of there and make more ponies. Brian and I talk about more of this stuff behind the scenes than we do on line here. I can tell you for certain that the ported stuff he does works period. If I was a turbo guy I would be on this like stink on roadkill. IMO your increased air flow from his porting work will perform exponentially better than trying to get there with heat reduction. I'm sure your already doing this. This post is for your benefit if you don't know this and for the benefit of others to think about.

Sometimes (and probably not you) people will skimp on parts of their car do to budget or in some cases they just don't know. Often these things that use to work just fine are now the weak links in the system. You are already addressing this with your frontal cooling upgrades (and I would NOT put an oil cooler in the middle along with the radiator and intercooler. If your running A/C then your asking for trouble. ****....might as well tape off the entire front end and restrict air flow even more. Use two oil coolers on the sides of the nose---the space is already there and you can easily expel air out the backside of them. Your logic is correct but go find somebody with a lot of experience to allow you to hear alternative approaches to your issue. I beleive you will find that putting all that jazz in the front middle of the car is self defeating. Make sense?

Eric