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jericker
07-15-2002, 06:29 PM
Hey everyone, has anyone tried venting the crank case through the exhaust to try to get a little more vacuum on the motor? If not, any thoughts on how it might work. I'm running a 1.9L Escort GT with EFI. Thanks, Jon

tschwenke
07-17-2002, 08:57 AM
Don't know about that one John but wanted to say good race. I saw you comming and was being pretty aggressive at putting lappers inbetween us. I had one heck of a race with two A's and about 4-5 laps in the tires started falling appart! You picked up some good time over the weekend and I was watching my lap times fall, meaning you were catching me FAST...

See you in August.

itbescort
07-17-2002, 12:13 PM
Just wondering why you need more vacuum? Most folks I know that have tried that have gotten black flagged for smoke after letting off the gas.
This is what we have done on our 1.9ís. I got one of the Jazz over flow cans and ran the PVC into the side. Out the top I ran the intake just behind the throttle body. I was hoping to trap extra oil from blow by. The hose that comes of the front of the valve cover I vented down to a small air filter. I was hoping to get some fresh air. What I found out is with 140 K on each motor my vent, vented out not in., so I cut open an old oil can and stuffed the breather in. I check it from time to time and drain any extra out. Now I have also found under heavy reving the PVC does not keep up with the vacuum. Hence sucks the sides of the over flow can in. I tried removing the PVC valve and the car would not run. Oh yea we are running 20-50 oil, which might be why the PCV valve is not keeping up.
None of this really answers your question just some things we have tried.
Tim



Originally posted by jericker:
Hey everyone, has anyone tried venting the crank case through the exhaust to try to get a little more vacuum on the motor? If not, any thoughts on how it might work. I'm running a 1.9L Escort GT with EFI. Thanks, Jon

joeg
07-17-2002, 01:21 PM
Tim--vacuum crankcase venting helps seal your rings and increases performance. Done via the old drag/roundy round trick with one way check valves connected to the exhaust system is, unfortunately, not permitted by the GCR.

It is probably a safety issue...

Alternatively, if you hook up your air pump from your emissions system to do the same thing, you would be violating ITCS because you would want to force the blow-by sucked out by the pump to a point other than your vehicles intake manifold (oil vapor lowers octane of the incoming air fuel mixture and promotes detonation).

jericker
07-17-2002, 09:02 PM
Originally posted by tschwenke:
Don't know about that one John but wanted to say good race. I saw you comming and was being pretty aggressive at putting lappers inbetween us. I had one heck of a race with two A's and about 4-5 laps in the tires started falling appart! You picked up some good time over the weekend and I was watching my lap times fall, meaning you were catching me FAST...
Hey Travis, I didn't know you were on this forum. I don't get on it much, only when I need some advice. I thought I had your butt on Sunday. I was definitely coming hard. I figured out a bad push problem I was having most of the weekend by the race on Sunday and the car was a rocket. If I had one more lap, I was there. That red ITA RX7 cost me. You and the black RX7 lapped him going into turn 1 but I caught him right in the middle of the turn and tried a bonehead move which almost did both of us in (won't try that one again). Anyway, it cost me about 3 seconds. I hope I can stay in the 1:52's in August, we'll see. Can't wait to do it again. BTW, have you checked the CenDiv points race. Do you think we can hold off Rotem and Chris? A one-two finish would look good wouldn't it? See ya in August. P.S. the crank case venting is illegal anyway, I missed it in the GCR.
See you in August.

jericker
07-17-2002, 09:18 PM
Originally posted by joeg:
Tim--vacuum crankcase venting helps seal your rings and increases performance. Done via the old drag/roundy round trick with one way check valves connected to the exhaust system is, unfortunately, not permitted by the GCR.

It is probably a safety issue...

Alternatively, if you hook up your air pump from your emissions system to do the same thing, you would be violating ITCS because you would want to force the blow-by sucked out by the pump to a point other than your vehicles intake manifold (oil vapor lowers octane of the incoming air fuel mixture and promotes detonation).


Thanks Joe, I couldn't have said it any better. Tim, I can't do it anyway because of GCR 17.26. I would have liked to increase some hp's by increasing the vacuum and sealing the rings better. I'll stick with my catch tank system like I have it.

tschwenke
07-19-2002, 09:54 AM
Yes, I am on this site. Read it regularly but don't always post. There were 3 or 4 corners just killing my lap times as the tires started going. I knew I had to put anything inbetween. I found that the Black RX7 lives about .5 mile from my place. I haven't taked to him yet but we one hell of a race along with 2 other ITA's. Two tires were about 70/80% corded (the fronts of course). I guess that 10 heat cycles are enough for those Hoosiers.

It was hard because you don't want to hurt them, but if I let them in front of me into 7 my lap was done. It was better running slower racing than running much slower being held up. A perfect case of cars running the same lap time but doing it in different ways.