RxRot

Hello all.

I've got a 94' Single Turbo that I have blown up twice now (1500 miles both times). I have been using the Hurley Heavy Duty 2MM w/ dual springs, but I think I am going to go 3MM (or larger?) this time for the (hopefully) increased reliability.

Can anyone offer some input as to what type of seal I should go with...
At present I am leaning towards the Hurley set.
Help would be appreciated.

Regards,
Gavin

mmaragos

2mm or 3mm is not going to make a difference if you are losing an engine in 1500 miles. The 2mm seals have been shown to hold up to significant pressure and HP, as long as you are tuned OK.

What has been the root cause of engine failure in each case?

I would make sure that I am not going to lose another engine to the same cause and I would use 2mm Hurley seals (if possible).

ErnieT

iTrader: (2)

I agree. Finding a shop to mill the rotors correctly to fit the 3mm will be the trick. Im sure you'll find arguments, but there will be nothing that fits better than 2mm. Also, I agree, I think you have engine building problems, not apex seal problems.

RxRot

In both cases one (or two) seals broke in the front rotor. The car is running 470HP at 14.7psi using a Haltech E6K (ignition cut at 7250) with MSD signal conditioners (which I have heard can be a potential problem). The car runs rich in the upper RPM range and the boost is not extremely high, so I thought it was simply (although it is surely not that simple) the strength of the seals.

Any more advice?

jimlab

Save your money. The 2mm seals are perfectly adequate. Instead of trying to find a "magical" seal that will keep from breaking, spend your time (and money) on finding the source of the problem.

Upgrade your fuel system, if you haven't already and ensure that the engine is being delivered adequate fuel. Have your injectors replaced or cleaned. Install a rising-rate fuel pressure regulator and *tune* it properly. And last, but not least, invest in an aftermarket engine control system (as it appears you have) and have it properly (likely professionaly) tuned *with* a reasonable safety margin.

Trying to cut corners and get the most horsepower possible is a mistake with the rotary. It will not tolerate lean conditions and additional fuel (and/or a stand-alone knock sensing system) is your best safeguard against detonation.

RxRot

Thanks for the reply...

This car was purchased from Ryan Schlagheck. It has an RP secondary fuel rail and an SX Performance rising rate fuel pressure regulator. The car was tuned, and as I said, runs rich into the upper RPM band, so I do not know what the problem is.

KZ1

maybe timing too advance, or shotty building of the engine.

SleepR1

It's just life in the physical world. 80 cubic inches of forced induced gasoline combustion just cannot support nearly 500 horsepower reliably. It's that simple! Mazda rotary engineers never intended for their 13BREW to put out that kind of power RELIABLY.

So just back the horsepower down to a sane level, and you'll see your motor actually make it past 1500 miles on the trip odometer!

ErnieT

iTrader: (2)

I disagree. Running 15psi on the street is perfectly fine and acceptable especially w/ Hurley double spring heavy racing apex seals. You will need to explore different options on why your motor failed, ie.....fuel pressure, faulty injector, any number of things....sorry to be so vague

RxRot

Thanks for the responses guys.

I think I will rebuild the motor with the same 2mm seals and take it down to AIM in Indy to have them check it out and, if needed, retune it. I am going to call them sometime today (hopefully).

I think I'll also drop the ignition cut down to 7K to avoid any leadfoot syndrome disaster! Would a knock-sensor be a good idea too?

Jim Swantko

Gavin,

Let us know what you find. Ryan and I use to cruise around a LOT together in our single turbos. I can't think of any corners which were cut in his car.

I am almost positive that he got the fuel maps from Steve Kan (then richened them up a bit on the top end). So I don't think anyone can say the tuning is crappy.

I was with him when it was on the dyno and it popped the first time. The A/Fs looked great (in the high 10s to low 11s if I recall)... the oil/water temps were great (I was spraying the IC/Radiator/Oil Coolers so I know they were cool) so I am really at a loss. I know that Dave at KDR rebuilt the motor before you bought the car from him. So the rebuild was quality.

The fuel system was good.. the ECU was good... the maps were good... I don't get it. I don't think the timing was touched... maybe retarded a bit for safety. This is one of those cars the had everything done right... tuned right... and still has problems.

I am baffled... I think the car may be cursed.

RICE RACING

This is a lot of crap !

For starters the 13B is the equiv of a 2.616lt engine, the BMEP figures and countless SAE papers on the topic confirm this......

The BMEP's run to develop 500BHP (this is engine power!) are very tolerable indeed, I have been doing so now for over 3 years with NO reliability problems at all.

Mazda designed the engine to support 255bhp every day of it's life with VERY mild rpm's and low mechanical stress !

500BHP is not only achievable VERY VERY easily, but it is also when done properly and staying with in thermodynamic and mechanical engineering limits of the engine VERY RELIABLE.

My engine has 525BHP @ 8000rpm on 1 bar boost (14.5) psi on pump gas, and has done over 30 000km or over 15 000miles !!!! of which over 1 500km has been at full load and full power, revs above 5500rpm on a circuit track.

I think that is RELIABLE in anyones books ?

Oh and as a side note, after inspection recently, I see no reason why the engine will not do 100 000km or 60 000miles at this power level with that amount (percentage) of race miles, as I have customers who have done exactly that.

Stop spreading falicies about "rotaries" not being reliable at high BHP's, it is simply bullshit !

RICE RACING

I use stock 2mm seals, no problems at all.

I even use them in a 13B Peripheral Port Turbo engine, with around double the power you have without any issues. They are a world class seal, I know they are harder than the Hurley seals from what others have told me.

All I can say is that I have NO problems what so ever with std Mazda 2mm seals, I would recommend them to you based on my experiences.

RxRot

Jim,

Everything you say is absolutely correct, I don't get it either. The first time it went, about a month after I picked it up, I spoke with Dave at KD many times about the situation...he mentioned pulling the MSD units (and changing the signal selection on the Haltech). Ari at RP sent me a wiring diagram to connect the ignition pickups directly to the Haltech, but I did not disconnect them, rather I sent the Haltech in to be checked, and it came out fine. Now it is the second time it has blown, in the EXACT fashion as the first, upper RPM's (around 7K+) blowing a seal in the front rotor (which I believe was the same outcome Ryan had a few times) and both times @ 1500 miles. I've spoken with multiple places about the issue with the general consensus being that there is a problem in the timing.

I've had mixed input regarding the 2mm vs. 3mm. What did you have in your car that big T-78? I remember it, that black beauty. I was contemplating sending you an offer, I wish I would have!!! Hurley makes race seals in 3mm...hmm. I talked to a guy named Skip from Revolution Rotary today about reconditioning my rotors and housings (which after two explosions have 3000 miles on them with no damage, luck?) and about milling out my rotors...he says he deals with a guy that seriously knows his stuff and could do it for me. I mean, I know that this would not fix the problem, but in the long run would it add reliability?

Right now I'm getting quotes on seals, gaskets, etc. I'm up in the air as to what route to take to try to solve this problem. I too am baffled.

jimlab

I think the main point that you're missing is that your *one* example does not constitute the *average*. Even a handful of Aussie engines running at that power level for a reasonable amount of time doesn't change the fact that in the United States, what people are faced with is that *on average*, high horsepower rotary engines really don't last that long. Sorry, but statistics are against you, no matter how zealous you are about your cause.

Now, would it be too much to ask for you to be fatally bitten by a King Brown so I don't have to hear about your f**king wonder engine again?

RICE RACING

OK, I get youre point

But seriously, it is possible to be reliable a that level....I have a few specific things that I adhere to %100 and some people do not agree with them. Certain a/f ratio's, plugs, turbo setup's (exhaust a/r) timing, ECU's and the adaption of water injection.

I have repeated these (one of engine) results a few times now, what the exact forumla for sucess is could be argued to death I suppose, all I know is that it works for me, my customers and my friends who ask for help in seting up their cars. I am very specific, as you need to be with these engines when you start pushing the boundries of performance, but without sounding arogant, it is possible to achieve what I have done with my engine, have power, economy, and be reliable.

I remember crispeed saying once that the haltech unit (do not know which one in particular) is not so accurate in the ignition firing, this could be a problem? causing the failures of the seal? All I can tell you is that the mechanical stress alone(at 500bhp power level) is not the root cause of the problem under "normal" operating conditions, you have a system or sub system problem causing youre failures, at a guess in youre ignition, if youre fuel set up checks out OK.

Freaky Monkey007

If i remember correctly when u have the engine rebuilt till like 3k miles ur not susposted to get above like 5k rpm's... Is this correct or am i just stupid?? I could of sworn that you were susposted to break in the engine before going to boost..

mmaragos

Break in should be along the lines of:

<4,000 RPM for the first 500 miles (variable RPMs, min. boost)

<6,000 RPM for the next 1000 miles (variable RPMs, low boost)

Some consider the second step optional.

jimlab

I totally agree. It is possible to be reliable at that level. But given most people's inability to tune their own car, their lack of proximity to a capable tuner and their budget for an aftermarket fuel and engine management system, it's not a reality for most people. Up here, people have trouble keeping 350 RWHP rotary engines running reliably, let alone 550.

LUV94RX7

iTrader: (3)

[QUOTE]Originally posted by RICE RACING and the adaption of water injection.QUOTE]

Seems like you have had good luck with high output rotaries. How much of that success do you think is due to water injection. I'm doing the same for reliability reasons.

Ken
'94 white, base, pep, red leather,
mods: Hayes street port & polished stage II, 3mm Hurley Racing seals,
XS T04e single turbo kit, GReddy SMIC(400cu.in.) Aquamist 2s water injection kit, AEM EMS, Pettit ss resonated MP, Pettit ss cat-back,
RP Racing fuel pump, 1600cc injectors, Profec B(10&20psi),
Centerforce clutch, under pulley kit(no air pump),
Pettit short shifter kit, boost gauge,
LaBreck's bushings, Evans Coolant

RICE RACING

I honestly believe ALOT of sucess is down to the water injection and rich a/f mixtures.

Last night I went driving/tunning in a maates car and it has one of my water injection set up's.

His specs are as follows.

20psi boost
8000rpm
RICE FMIC
880cc injectors x 4
Malpassi fuel reg
10 deg advance at full boost, MSD 6A on leading, 12a distrubutor, B10EGV spark plugs
a/f ratio at full load of 10.8 to 11.2:1
RICE water injection kit, switch on at 11.5 psi @ 20 psi flows 300ml/min
Microtech ECU
Engine was rebuilt by me 2 years ago to std specs (seals stock, porting near stock), and has done 5000km in this high state of tune.

Engine making at the moment 460bhp to 470bhp. The water injection if run at this flow rate requires a strong ignition system, eg a CD type to fire the mixture. Any how last night we did a total of about 20 runs from a stanting start up to 130mph to set the final boost correctly and trim the fuel, it was great fun and the car ran like a dream, the compression has stayed the same for a whole year and she is very strong, my mate is one happy boy ... me too, last night was alot of fun !

Jim Swantko

Gavin,

I had stock 2mm seals. Thanks for the compliments BTW. I don't understand it man... I hope you get it sorted out.

I don't think that you NEED the 3mm's .... many are making big numbers with stock 2mm's. There is something just wrong somewhere... Did you have Ari look at the Haltech maps? I know that Ryan had a new ignition put in the car after the first motor went.

Good luck Gavin..

yzf-r1

iTrader: (1)

Gavin,

I talked with you on the phone after the engine popped the first time, right after you bought it form Ryan, and you said there were alot of "deposits" on the rotors, which would be unusual for such a low mileage engine that was, according to Ryan, compeltely rebuilt by KD with new rotors and rotor housings....did you ever determine the cause of these "deposits"? just curious

something is really fishy with that car.....wow, I'm glad I didn't buy it, I was all ready to...especially after looking at Swantko's clunker

haha, JUST KIDDING Jim

pluto

Sorry, I didn't see this post until today. If you're having problems with your car breaking up at higher rpm. I think your trigger sensor is either going bad or your home trigger is too close to the sensor. I have had this problem with my car on the haltech. It breaks up at 5.5krpm nomatter what load I was in. I hooked up an O-scope and found a double image of the trigger adjacent to each other. That's when I realized that the trigger wheel was too close because it picks up magnetic field and at a certain speed, the nipple of the wheel goes by and creates a double image of itself at a different frequency. So the haltech has no idea where the beginning of the TDC is and creates false ignition pulse. I bend the nipple out and the problem went away. Now I have a new problem (probably similar) at 7krpm and up. Since I pulled my motor in and out so many times last year, I think I mis-aligned it. I'll have to find an O-scope to fix this again. This is something that an average mechanic or tuner never thought off. I guess it's a good thing that I'm an electrical engineer so I know where to look when I see things that may cause other than something random. I think your problem is probably the exact same of what I'm experiencing. Try to bend out the home trigger nipple on your trigger wheel a little and see if it fixes it.

Good luck.

Steve Kan

yzf-r1

iTrader: (1)

I think if anyone on here knows about high hp rotaries, it has to be pluto