Well was in 3rd gear between turn 7 and 8 at shannonville motorsports park, 6400 rpms aprox. Chasing down a black M roadtster, 100% throttle, Huge stutter, lift gas pedal. No power. AFR was around 11.7, New plugs, two crane Hi-6 Ignition boxes, two LX92 coils, new plug wires.



History:

Dyno'd the car at 231 rear wheel horsepower,

AFR was in the high 10s, low 11s

hit 11 psi on the dyno.



Noticed: Car was hesitating/sugring/flat spots on the dyno as she made her runs, took some fuel out, it got better, not as pronounced. I thought it was a flakey FCD and I was hitting fuel cut. I checked the FCD later and found it clamped at 8 psi voltage exactly. Didn't think much of it.



Took the car to the 1st time trial race of the season. Air temp was cold... started to boost high all the time. The surging/flat spots came back big time. I would lift to 3/4 throttle from 100% thorttle whenever I felt that surge and I was able to drive through it. Kept on doing that all saturday. Same thing happned at warm up laps today, did about 1 hour of practice laps. Noticed it was hesitating not surging now. Took a gander at the AFR gauge whe I was running max boost 13.65 at 6500 rpms in 3rd, the AFR was between 11.5 to 11.7. Thought all was ok

Then the motor went a couple of laps later.



Pulled the plug from each rotor and listened. No comression on front. I thought the rear blew because Fuel cut due to over boost would normally cut the fuel to the rear rotor no?



The car still idled at 500 to 600 rpm with --54 mmHG vac or basically no vac at all. I managed to limp the car about 60 kms on the free way doing 60 mph before it wouldn't hold 60 moh and I had to get towed home. The car would buck/hestiate at around 4000 to 4500 rpm, and again at 6000 at anything more than 3/4 throttle. AFR would jump to 18 to 20 AFR during this buck when it was running on one rotor.



What caused the motor to fail? was it too much timing on the stock ECU for 13.5 psi? Too lean? Electronics problem with the TPS/ECU/other sensors?



Motor had 132,000 miles on it.



MOds related to engine:

2X Crane Hi-6

2X Crane Lx92 coils

680cc secondaries

Apex-i SAFC

Aprx-i AVCR

Paul Stokes DIY FCD

Sorry to hear that man... are you running NASA events, jw?



Either way, I would blame the stock ECU.. I wouldn't think it could handle 13.5 as far as timing goes... the crane units only provide a more powerful spark correct? They don't do much for adjustment of timing, which is what you would probably have needed at 12+ psi at over 6K RPM..... sounds like it's time for a standalone on your next motor....



I think you had enough fuel... the larger secondaries w/ the s-afc should have been enough.. i would really lean towards ignition timing...

Another quick note, at 132K miles on the motor... if it was the factory one, I wouldn't think it would take many pings before letting go...

132000 and 13psi, im not surprised you broke a seal. Not to mention the stock ecu thinks your running 8psi.



Did you dial back the CAS/timing any?

That would be a big N O.

=(



I hate to admit this, but for 5 years I've owned the car I've been running stock boost. I thought I could squeeze some more juice from the engine by adding a Cone filter and 3" aluminum bent pipe for TID. I got too greedy with not enough time to play around with the car before the 1st event. I'm going to admit that I'm a pretty newb when it comes to engine and power stuff. I only really understand suspension, brakes and tires.



And yes I do run a form of NASA event, but with the CASC (which is the equivalanet of SCCA for Canadians). The timed competitions are called Solo1 racing. 6 cars equally spaced trying to set the fastest time in your class.

is there a front mount? or are using a stock ic?

Stock IC.

and it was the original engine and turbo that came with the car 17 years ago and 132,000 miles ago.

i think you're running too much boost, which with the teeny turbo and so so ic = high intake temps; add a little lean and its boom!



keeping the motor together is a balancing act, if you keep the water and oil temps down, lean is ok. the factory setup lets temps go (as you're not gonna be on it that long, right?) and runs it rich.

Yea this motor was not built with the supporting mods. Your probably had lower compression over boosting the stock turbo and way over heating the capability’s of the TMIC without proper tuning setup.



The stock ignition is good for 500whp upgrading it is wasted effort.



Try it again just be more intuit to your tuning equipment and supporting mods. go fast and cutting corners will always yield a popped motor.

yeah id say it wasnt that big of suprize it let go, especiall running that high of boost on the stock IC, being on the track your running it hard for extened periods intake temps can get real high on that lil IC... not to mention at 132K miles being close to 20 yrs old its no wonder it let go.... it was prolly close to its time to go anyway.

I wanted 150,000 miles. I got too greedy and started to increase the boost to compensate for my lack of driving skill. =(

Lol, its ok... I've blown my fare share of motors too https://www.nopistons.com/forums/pub...IR



At least now you get to move to the next level of a rebuild. You plan on doing it yourself first time out, or sending it off/mail order?

we tuned steves car (e6k) and the ic actually does an ok job, temp goes up, but the scoop works, and they come right down the second you lift. granted with the stock turbo, they are too high to start with....

I was going to pull the motor out, all the items mounted in the engine bay off and towing it to a body shop to straighten the rad support, replace a fender and paint the engine bay. Both frame rails are missing paint due to failed ABS pump and failed master during the life of the car.



Engine wise: I was thinking of building up the motor myself. Stock ports. But I plan on polishing them up. I also plan on port matching the intake manifolds and porting the throttle body. Send the manifolds out for silver powder coating. I will for sure port the wastegate out as big as I can. Then I plan on port matching the exhaust manifold if it requires it. I may send the exhaust mani out for ceramic coating... not sure yet. I want to run two egt probes in each runner of the manifold. I have a brand new S5TII Turbo sitting in a box downstairs so that will be put to good use.



I'm not sure if I want to run a e6x. If the engine harness is bad, or too many sensors are fubar I may use the e6x so that I can stop worrying about 17 year old sensors and crispy harness.



A lot of work. Especaily when i'm at the stage of wanting to buy a condo

Here's a pic of my car when it was still running. She's a bit too nice of a condition to part her out and sell as a rolling shell

I want to make 194 rear wheel horsepower on a dynojet to drop a class. This year I was running SGT3 due to rule book changes. I need to drop back to GT1 which I ran last year to still be competitive. I tried to squeeze the turbo for more HP to make me more competitve for 2006, but it didn't work. I blew the motor and even when I was pushing the 13 psi before she blew I only ran down the 4th place car which was a stock FD on Hoosiers.



She dyno'd 208 rear wheel HP on a mustang dyno. People say you get 10% less on a mustang instead of a dynojet? I'm not sure.



What I want is to have a super low boost threshold. Make full boost with the stock turbo at 2500 rpm and be able to hold that to redline. About 9 psi worth.

I fully understand the wanting to drop a class! We went through that with my buddies miata in CSP and SP2... either way, polishing the ports would be a good start, i was going to say do a mild port job, but not if you want to drop back a little. Maybe you should still do the port to help w/ the top end a little and just run lower boost like 8 to 9psi..i don't think you'd make too much over 190whp... you can always dial it back, but at least if the motor is ported some, you could go up too... change classes when you want.



Sweet looking car btw...

on my t2 i cleaned up the casting flash in the intake runners, and made the exhaust port line up with the sleeve (it went down maybe 2mm?) and i had no trouble running .4bar on a stock s5 turbo. it would hold that boost all the way to redline too, so it actually had a powerband over 5000.



other relavent mods, rb turboback, s5 tid, cone filter.



oh and i also polished the inside of the stock tb elbow, its the smallest point in the intake system

Diddo on the polished stock TB elbow.... I still have mine somewhere..i think it's in the back of friends T2...

Stock TB elbow? That is the one that adapts the top mount intercooler to the TB?

yep

ya