9krpmrx8's Boost Build Thread
I said pressure in the manifold, which I assumed he meant when he posted that. Normally the manifold would be under vacuum at part throttle and low or no vacuum under WOT for an NA engine. Though it could go slightly positive with high efficiency from intake pulse tuning, but I doubt it is 1 psig and it would be it's highest at the TQ peak on an NA engine which for me is at 7000 rpm. I was just making an assumption in general. It would really come down to the MAF reading at 1 psig boost vs NA WOT at the same moment, so I could be wrong (and probably am). The point is he should still be careful during break-in regardless. That's why he's breaking it in to begin with.
if he has the data at that point I could compare it to my own.
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if he has the data at that point I could compare it to my own.
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Last edited by TeamRX8; Dec 11, 2011 at 07:59 PM.
It's not weather the bov is cheap or not - it's weather it is set up properly . Most aren't - as we have already discovered in this thread .
Last edited by Brettus; Dec 11, 2011 at 10:18 PM.
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Yeah I really have been taking it easy. I have been monitoring Absolute Load and I have not gone above 50 so I think I am okay. But either way I'm not pushing it. I actually measured oil pressure today at the turbo and it was way too high (as high as 70 psi during normal driving) so I went ahead an installed the restrictor from ATP because when I redline the pressure will be way too much. The pressure with the restrictor maxed out at about 40 psi so it definitely works and I should be okay with max psi at redline (I hope).
unfortunately it is not that accessible for the average joe, it usually is employed on a race engine dyno
http://www.taylordyno.com/catalog/dy...s/blowby-meter
http://www.aa1car.com/library/engine_blowby.htm
http://www.taylordyno.com/catalog/dy...s/blowby-meter
http://www.aa1car.com/library/engine_blowby.htm
are you concerned about blow by?
doesnt the oil pressure restrictor also affect volumne of flow to the turbo? Is that OK? Probably is, I am just lurking and trying to learn a little about turbos.
Even when you are not in boost--think about what is happening in the intake, it is much different than NA. Thats why the car feels stronger than na even without any boost showing on your gauge.
Dont go just by a/f's concerning gas. Your intake charge temperature, engine temperature and your true octane/timing all have a very important affect. If you are going to hang in the boost much--you need a better gas than pump and with a higher octane.
Only options I know ( I dont like w/m to control octane)
1- xylene
2- toluene
3-Torco accellerator
4- race gas
Thats it.
Are you running the oem sparkplugs--or have you gotten the colder versions?
I have never had much luck with the rx7 barless type--they just dont last very long for me. I have the step colder denso's and use an ultrasonic cleaning machine to bring them back when needed--it has worked so far.
Now keep that thing straight in the road
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doesnt the oil pressure restrictor also affect volumne of flow to the turbo? Is that OK? Probably is, I am just lurking and trying to learn a little about turbos.
Even when you are not in boost--think about what is happening in the intake, it is much different than NA. Thats why the car feels stronger than na even without any boost showing on your gauge.
Dont go just by a/f's concerning gas. Your intake charge temperature, engine temperature and your true octane/timing all have a very important affect. If you are going to hang in the boost much--you need a better gas than pump and with a higher octane.
Only options I know ( I dont like w/m to control octane)
1- xylene
2- toluene
3-Torco accellerator
4- race gas
Thats it.
Are you running the oem sparkplugs--or have you gotten the colder versions?
I have never had much luck with the rx7 barless type--they just dont last very long for me. I have the step colder denso's and use an ultrasonic cleaning machine to bring them back when needed--it has worked so far.
Now keep that thing straight in the road

.
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Thanks. I have been reading a lot on turbo oil feed, drain, and crank case pressure.
I searched a bit here and I see some discussion on restrictors and the oil drain but it does not appear anyone else has actually tested to insure the turbo is getting the proper amount of oil as outlined by the manufacturer. I mean my engine should see almost 130PSI at red line (I'm guessing based on what my last motor saw with the Mazmart oil pressure mod) so that is twice what a typical journal bearing turbo should see max. So what is that doing to a Greddy turbo that should only see 66PSI maximum oil pressure?
Everything I have read has stated a restrictor should only be used as a last resort and that the drain and crank case pressure should be looked at first and that properly designed system should not need a restrictor. That said, restrictors have been used from the factory in some Mitsubishi's. I found some oil in my charge pipe so I am going to have get a catch can after all.
I searched a bit here and I see some discussion on restrictors and the oil drain but it does not appear anyone else has actually tested to insure the turbo is getting the proper amount of oil as outlined by the manufacturer. I mean my engine should see almost 130PSI at red line (I'm guessing based on what my last motor saw with the Mazmart oil pressure mod) so that is twice what a typical journal bearing turbo should see max. So what is that doing to a Greddy turbo that should only see 66PSI maximum oil pressure?
Everything I have read has stated a restrictor should only be used as a last resort and that the drain and crank case pressure should be looked at first and that properly designed system should not need a restrictor. That said, restrictors have been used from the factory in some Mitsubishi's. I found some oil in my charge pipe so I am going to have get a catch can after all.
Thread Starter
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are you concerned about blow by?
doesnt the oil pressure restrictor also affect volumne of flow to the turbo? Is that OK? Probably is, I am just lurking and trying to learn a little about turbos.
Even when you are not in boost--think about what is happening in the intake, it is much different than NA. Thats why the car feels stronger than na even without any boost showing on your gauge.
Dont go just by a/f's concerning gas. Your intake charge temperature, engine temperature and your true octane/timing all have a very important affect. If you are going to hang in the boost much--you need a better gas than pump and with a higher octane.
Only options I know ( I dont like w/m to control octane)
1- xylene
2- toluene
3-Torco accellerator
4- race gas
Thats it.
Are you running the oem sparkplugs--or have you gotten the colder versions?
I have never had much luck with the rx7 barless type--they just dont last very long for me. I have the step colder denso's and use an ultrasonic cleaning machine to bring them back when needed--it has worked so far.
Now keep that thing straight in the road
.
doesnt the oil pressure restrictor also affect volumne of flow to the turbo? Is that OK? Probably is, I am just lurking and trying to learn a little about turbos.
Even when you are not in boost--think about what is happening in the intake, it is much different than NA. Thats why the car feels stronger than na even without any boost showing on your gauge.
Dont go just by a/f's concerning gas. Your intake charge temperature, engine temperature and your true octane/timing all have a very important affect. If you are going to hang in the boost much--you need a better gas than pump and with a higher octane.
Only options I know ( I dont like w/m to control octane)
1- xylene
2- toluene
3-Torco accellerator
4- race gas
Thats it.
Are you running the oem sparkplugs--or have you gotten the colder versions?
I have never had much luck with the rx7 barless type--they just dont last very long for me. I have the step colder denso's and use an ultrasonic cleaning machine to bring them back when needed--it has worked so far.
Now keep that thing straight in the road

.
Which combo do you recommend? I have read several different opinions but I am still confused as to which is best.
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I will run synthetic and idemitsu in the SOHN reservoir. Having occasionally engine oil go into the SOHN reservoir won't hurt anything. And you don't want the catch can air tight, that will cause excessive crank case pressure. The problem with my cheapy catch can is that it does not vent enough because the fitting are too small.
With boost you need to run a check valve if you run the line to the intake from the can. You dont want to pressurize your system.
Dose your pump pressurize your crank case?
Dose your pump pressurize your crank case?
^ what, you dont see boost from a pre turbo vacuum nipple, It will always be vacuum... I may be misunderstanding what your trying to say hoss, but you should not need a check valve for the catch can
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You mean one way from the oil filler tube to the intake? No, there is no return pressure there. The pump may pressurize it a bit I guess.
lol sorry! you guys are right.. its late here and I am only half paying attention. Yeah that is the one I was talking about 9k. If your pump adds anymore pressure I can see how it could cause more then normal oil build up.
BUR9EQP in leading and stock trailing is the proven plug combination for street driven turbo RX8s
As OD mentioned the BUR9s don't last long - but they are very cheap . I change mine at each oil change (8000kms).
As OD mentioned the BUR9s don't last long - but they are very cheap . I change mine at each oil change (8000kms).
/\ well , I actually run The BUR9s in the trailing as well . So I change the leading each oil change and the trailing every 2nd oil change because they last longer in the trailing position.
At $7.00 odd per plug it is still more economical than using iridium plugs .
At $7.00 odd per plug it is still more economical than using iridium plugs .
Last edited by Brettus; Dec 12, 2011 at 01:27 PM.
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