radiantRX-7

iTrader: (1)

Hello everyone, well here it goes. Got my rotor housings ported and coated by Mazda Trix. Have a 500R signal turbo apex standalone and was tuned b Steve Kan.

The engine was broken in the proper way I did everything possible to make the perfect set up . When Steve tuned it was only like 260 to the wheels at 10psi. Which was really low in my option? He said that the clutch wasn’t holding up well, however it was new also a ACT6 puck.

When I brought the rotor housings to pettit racing Cam told me he didn’t like the way they did the port job cause it wasn’t biased enough and that it was to straight , me being stubborn didn’t want to listen and went with it anyways. So the engine was built by Cam stock 2 mm. seals 2 piece dowel pined. 850cc. primaries and 1680cc. secondaries injectors. When the car was built the engine ran rough and the vac, sometimes was around 16. Other time sit was around 18-19.

I felt that the engine wasn’t done right and something was wrong with the low HP numbers and all. So the other week I had the car out and open it up a bit in 2nd. Was at 12. Psi. right when I got to 7-8rpm I went to shift and then it went out stalled ad just died. I coasted to a gas station and got it flat bedded straight to Pettit . There were no leaks just 0 compression. The engine will just whine when you try to start it.

So I get to Pettit and see him the next day. He was like I really can’t give you a free re-build cause you got the rotor housing ported by someone else, which in a way he is right but the engine was brand new and shouldn’t have popped so quickly. So here is the million dollar question, can a new engine break so fast with a bad port? Just seems really unusual why didn’t it go out on the dyno? Steve did about 10, 8K rpm pulls.

Cam and I came half way and decided that I will pay for the parts and he will do the labor. I know it was partly my fault so that’s why I agreed to pay for parts. It just really sucks that my engine went out so fast. I have a cool mist sage 3 . And as soon as this one gets built that is going in ASAP I don’t care meth is going through the engine at 10psi. Another thing Cam mentioned was that the 10% ethoal was killing all our engines and we should run 2-3 gallons of race gas to be sure that the octane will be at least 93. I guess the ethoal was lowering the grade.

I will like everyone’s feed back please and let me know what I should do better or what I did wrong. I know this time Cam will do all the porting for me. I wonder if Mazda Trix will refund me the rotor housings? Cam hasn’t opened the engine yet to find out what happened exactly. But my guess is that the apex seal went out.
Thank for the input.

theorie

iTrader: (31)

wow you're calling foul on a quite a few respectable people here.

maybe it's how you drove it? lol

ah bad luck perhaps...

bring the car to advanced race technology here in sarasota next time. we just dyno'd my car tonight at 380 horses on the stock turbos.

radiantRX-7

iTrader: (1)

I pretty sure I didn't over boost it I have a Greddy boost controller. And it was at 12psi.

spoolage

iTrader: (2)

This is why I just go with Mazda Remans --- I had an oil seal issue on my engine and then less than 5k miles in I chip an apex seal... Ray offers a 1 year, unlimited mile warranty and he stands by it --- he did not have any reman engines in stock... only new never used motors, straight from japan and that is what he gave me.

The best part of using reman / stock port engines versus a ported motor --- the map stays relatively similar to the previous motor. Also, for me -- the HP I can make with my setup on stock ports (400 - 450) is more than enough for my needs.

Mahjik

iTrader: (1)

Did you at any time during those 4000 miles, compression test the engine? Cam is really helping you out on this one. You pick up a motor, and don't come back for 4000 miles. When you do, the engine is blown. I'm not sure what you expect a shop to do as anything can happen outside of their control during that time.

PDViper77

iTrader: (9)

I don't think that the 10% ethanol lowers the octane rating but it will make the car run a hair leaner than a car with 100% 93 octane gas and 0% methanol. Does this make sense?

855m0n0

iTrader: (1)

I blew my last 13b motor (4th one btw) in 4000 miles. It was built and ported by Mandaville and professionally tuned, bla bla bla. I had a wide band and the AFRs were always good. However, big power +rotary often (not always) but often ends in expensive repairs. Now I have a LS1 motor. I only make 360whp(vs 450whp in the rotary setup) but the car weights 40lbs less and makes 300 ft/lbs of torque at 1400rpms and tops out at 355ft/lbs of torque. 32mpg on the highway is nice too. If I feel like it I can easily get 430+whp with a few bolt ons (head/cam) but the car is FAST as is and I was able to smoke several built Z06 vettes at Talledega at my last track day.

s-thetikz

iTrader: (1)

no one cares about that filth, stop advertising it. (stop convincing me)

my rotary is from pineapple and has been wonderful. It really is all in the build- gotta do the research yourself too. don't sell out

djseven

iTrader: (56)

Go with ALS apex seals this time and take it to Ray Wilson for the tune. Nothing against anyone mentioned but Ray is the man when it comes to tuning and I believe teh ALS seals are proven at this point. A small price to pay to not have to experience this again in 4k miles.

I dont understand why the engine was built if the builder thought the porting to be an issue? Or maybe I misunderstood here? If the porting was bad enough to cause apex seal damage the engine should have never been built.

thewird

iTrader: (8)

I had my 2nd motor blow on me after 2,000 km (1,200 miles) because my BNR twins took a **** (BNR says they were oversped due to stock BOV's and it coincides with what happened) and drained all the oil so fast out of the motor that I heat scored the side plates and fused the side seals.

When I was tuning my 3rd motor (current), after hours of tuning on the dyno, my AFR's just started going leaner and leaner. After some diagnosing thanks to Dragonworks we realized it was the fuel pump crimps and redid it. If it didn't happen at the dyno, it could have happened sometime later at the track. I have wideband so I would probably notice it however most people that get their cars tuned don't. Point is stupid **** unrelated to the motor itself can cause your motor to blow. I'm actually surprised Cam is giving you the deal he is since he knows this and didn't like the porting to begin with, consider yourself lucky.

thewird

Tom93R1

iTrader: (2)

What condition is your wire harness in? Guite often the problem lies within an auxiliary component.

radiantRX-7

iTrader: (1)

Wire harness was brand new with rebuild.

Yes , he is hooking me up big time. Your right about tuning.

YES

No didn't compression test , I should have done it, that was my fault big time.


where can I get these seals? I don't think cam will use anything besides his own stuff this time around.



Sorry dot know how to quote.

IRPerformance

iTrader: (41)

Did you have the motor torn down yet? What was wrong with the ports? If you port up on the exhaust ports and don't re-create the factory bevel, the apex seal will crash into a knife edge as the port closes. This will cause extremely quick apex seal wear and eventually they break.

gracer7-rx7

iTrader: (16)

Wow. Cam is really taking care of you. Anyone else would have told you to **** off.

radiantRX-7

iTrader: (1)

Ihor!!!OMG that's exactly what Cam said. ****, I really feel that Mazda trix didnt do it right. I should have listened to Cam.

radiantRX-7

iTrader: (1)

No the motor isn't broken down yet.

thewird

iTrader: (8)

Once its torn down, the motor should tell the tail of what happened at least. Post some pics.

thewird

radiantRX-7

iTrader: (1)

I have a pic f the rotor housing before they went in but not the side of the port. Yes it had re of a straight edge to it. And Cam said it needed to be more curved. So that the seal will hit it less or less f an impact.

spoolage

iTrader: (2)

You were warned and you did not listen... The only hope you have is to take up this matter with Mazdatrix if that was in fact the culprit.

gusfd3s

Actually it is the other way around, ethanol is a higher octane fuel and will add octane to gasoline when blended.

As long as the engine is tuned for the 10% ethanol there should be no problem.

One problem could be if the ethanol percentage is unconsistant in the fuel, if you get one tank with 15% ethanol for some reason it will lead to a leaner mixture and that can be dangerous if you already are on the lean side..

I always keep one eye on the wideband when driving my 7, always.

Howard Coleman

iTrader: (6)

'sorry to hear about your problem.

if built, tuned and fixtured right the turbo'd rotary is a kick *** dependable motor. it is, however, a race motor.

don't think so?

the 13B is but 159 cubic inches displacement. most of us on this board think that a 400 rwhp FD is modest as far as output. 400 is 460 flywheel hp.

400 rwhp is 2.89 hp per cubic inch!!!

compare 2.89 hp per cu inch w corvette's hand built titanium rod, dry sumped 505 hp 427 LS7.... 1.18 hp per cu inch.

there's no mystery here, it it the vast amount of airflow due to the turbo that packs enough air into our 159 cu inch motors to make 400, 500, even 1000 rear wheel hp.

things get crazy inside the combustion chamber at 2.89 hp per cubic inch. there is a huge amount of Combustion Chamber Pressure (CCP).

things have to be just right to live in this enviornment. especially when the rotary does have a somewhat less robust mechanical architecture... i am talking apex seals versus piston rings.

so does this doom the rotary? no. but it does mean that it is more important to build, fixture and tune it right.

i pulled my motor a month ago just to see what was going on inside. it had been in my car for 4 years, 14,000 miles, over 120 dyno pulls and had made 498 at 20 psi. at the time i pulled it it was making 17 inches of vacuum and running perfectly.

the engine had almost no carbon and the side seals showed but one thousandth wear. bearings perfect. i will put it back together and it is ready for another 4 years of use.

that's what you get when you build, fixture and tune a rotary right.

of course various subsystem malfunctions or install errors can ruin any motor... as thewird posts... and then there's driver error. i built a motor for a friend and he called to tell me after few months of happy motoring that it had blown. i asked him what happened and he said he had been in the top of 4th gear on an incline (bridge) at one bar and it just lost compression. 'turned out he was running on an eighth of a tank of gas! on an incline, accelerating. he had just run lean which is a no no. other driver errors are boosting when the oil is still cool etc.

a turbo'd rotary is a racehorse and as such needs to be more carefully ridden.

learn how and you will enjoy the ride.

as to specifics here...

you have assembled some nice pieces. it will be extremely interesting to see what happened inside your motor and it will be an easy diagnosis. rotaries don't just "blow." there is always a reason.

while people can make mistakes i find it hard to believe that Mazdatrix would send you a set of ported housings that would be so screwed that they would take out your apex seal in 4K. not to say it couldn't happen... just that they have been successfully doing rotaries since the late 70s.

Cam is as good as they come. i used to race w him in GT3 and count him as a friend. Cam tends to be conservative generally as to porting and considering he has literally built more than a thousand rotaries his advice is solid. port too large and your motor will eat seals plus there's diminishing power returns. so while Cam may have had an issue w your exhaust ports it was probably of a philosophical variety. if the port was life threatening i doubt if he would have put his name on the build.

as far as the comment on another brand of apex seals, the inference being that the Mazda seals may have been the problem or another brand of steel seal may have avoided the problem... no. amongst steel apex seals Mazda is excellent and the specific seal is not your problem. it may have broken but there will be an external cause.

the "F" word fixturing is important. fixturing is selecting the correct supportive hardware for your motor. please do check out my recent thread in the 3rd Gen section... "Making the case for the <rotary> FD: the fix"

we are all very interested in what you find so keep us posted.

good luck,

howard

IRPerformance

iTrader: (41)

I've taken apart tons of motors and and a handful had the exhaust ports done this way. Its a common overlook. Many people don't know or just forget. No template is going to tell you to do this. You just have to know.

djseven

iTrader: (56)

I cant speak for Cam but I think he is talking about something different than you Ihor, Cam/Pettit likes to do a D shaped rotor with the oval edge being the closing edge, they do not rebevel the port atleast from the 10 or so motors I have seen from them. I even have one in the garage at the moment.

I think Cam's theory is the port is too wide at the closing edge and that is what causes the damage. However, I agree with Ihor that it must have a beveled edge to prevent seal damage over time.

I can not speak for Cam and am only going off the description the OP posted and what I have seen.

TimeMachine

iTrader: (10)

I'm thinking along these lines as well... Anxious to see pics from the tear down.

jeff p

I think Cam and the members of pettit racing are great people. they have always been honest with me and willing to spend time on the phone helping me work through a problem when others would want to charge you. I think Cam is being a straight up guy in your case I don't know anyone who would stand by work done by someone else. most people use others work as an excuse to get out of their own failures and pass blame.

Hey anyone know what happened to Jeff! he left pettit, he was always great to deal with.


Jeff