Jims5543

I do not know why my engine is still running. I mean it should have popped.



At this weekends Autocross I inadvertantly turned off my Profec B.

It was just before my last run and the track was damp from a light rain. When I shifter to second gear my tires broke totally loose and I fishtailed like never before. I hit third and the car was pulling like a ****** I mean it broke the tires loose again and I had to lighten up on the throttle. Then I heard the car break up and I let off the gas immediately. I drove the rest of my run at partial throttle not really pushing it at all.





I get into the staging area and I am like WTF!! is going on here. Why is this car breaking up. I hit the peak hold button on my boost guage and it is pegged at 2 bar!!! I immediately go back to the pits break out my laptop and download the last run. Lean as hell!! 1.2 lambda and the boost was off the chart. (2 bar sensor)





QUESTION:



How the hell did my car manage 30+ lbs of boost with no boost controller?? I never saw more than 1 bar uncontrolled before.



I have an 8 lb. spring in my wastegate and when I dyno my car hits 1 bar down low and looses boost from 5.5K on up to redline usually dropping down to 0.6 bar at 8K RPM. So does anyone have a clue why suddenly I am capable of boosting 30 PSI with out a boost controller??



I am baffled.



Once I turned back on my Profec B it held rock steady at 1 bar.







I am not entirly sure I did not hurt it. I will know for sure tomarrow. I am ging to do a compression check. It idles fine and runs strong the only thing that concerns me right now is that it didn't want to start twice today at the Autocross.



I was running pure 110 race gas with 100:1 premix. I knew we were going to run it hard so I put the gas in for insurance. I guess that was a smart move in hindsight.



I also have my car tuned very rich. When we dyno'd it last O2 was right at 11 all the way across the powerband.



We also have the timing very conservative and I think that helped too. Plus the ambient was down and the air was very damp. Fresh rain.



I hope I got lucky. If not I will let Cameron w/ Pettit do his thing on it.

1Revvin7

Yeah thats crazy, didn't someone mention the lean condition....

j9fd3s

well some thing like this happened to a buddy of mine, the diaphram broke in the wastegate so it was intermittantly pegging the map sensor in the power fc. it looks like your maps are good at high boost though, his maps werent good at high boost, it bent the rotors.



mike

Silver Ninety Three

Maybe the boost controller is not hooked up right? Mine runs off the wastegate spring with the profec off. How do you have it hooked up?

vosko

2bar goddamn.... i bet your T04 wasn't happy too!

Jims5543

I am starting to think that j9fd3s nailed it. When we first got this car running we did not use the boost controller and it never went over 1 bar actually it was more like 0.8 bar.



I have it up in the air right now so I'll take apart the wastegate and have a look.





Loi - I need my springs

dvls-7

yeah that does sound like the controller is not hooked up right....either that or just one of those fluke things that are too accustomed to happening with RX7s.

j9fd3s

what wastegate do you have?



mike

Srce

Damn that's a lot of boost!!!

Jims5543

I have a HKS T-04E single conversion. Its a HKS wastegate and it has an 8 lb. spring in it.



I did a real rough compression test yesterday with a regular compression testor not a rotary one. I had 3 consistent bumps at 75 PSI on both rotors. I am not sure the guage is correct. I am going to take it to Pettit Racing and have it done for real.



I pulled my plugs and they looked fouled. So I am putting in a fresh set.



Does anyone know what the compression is for an FD in PSI??