9krpmrx8's Boost Build Thread
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Well it rained today so only a few minutes of fun today at around 9psi after fixing (removing it all together) a vacuum leak due to a poorly machined vacuum distribution block. But I need to get some logs to my tuner for a slight retune. I fixed so many things that I am not sure which changed the tune but I am getting too rich (10.3's and even at the lower limit of the guage at 10.0) under boost in the low gears and I am getting some spark blow out.
But overall everything is working great and in 3rd with a careful modulation of throttle the ignition some times won't break up and it pulls like hell at 9 psi even while being on the rich side. I am sure being pig rich is limiting power quite a bit but still a huge difference from before, my heart was pumping. But it was tuned with a slightly cracked manifold and a faulty wastegate actuator (unaware) before so that is why it was not holding boost on the dyno. Steve says a few adjustments should have me back at the target AFR's under boost so hopefully he can shoot a tune to me after I get him some logs and I will be ready for some test runs.
The turbo oil pressure regulator setup is working great, the turbo is only seeing 60psi max at redline. And the separate cooling circuit (pump, cooler, and reservoir) for the turbo is also working great, the reservoir is only slightly warm to the touch after a bit of hard driving yesterday.
Oh and I got this
But overall everything is working great and in 3rd with a careful modulation of throttle the ignition some times won't break up and it pulls like hell at 9 psi even while being on the rich side. I am sure being pig rich is limiting power quite a bit but still a huge difference from before, my heart was pumping. But it was tuned with a slightly cracked manifold and a faulty wastegate actuator (unaware) before so that is why it was not holding boost on the dyno. Steve says a few adjustments should have me back at the target AFR's under boost so hopefully he can shoot a tune to me after I get him some logs and I will be ready for some test runs.
The turbo oil pressure regulator setup is working great, the turbo is only seeing 60psi max at redline. And the separate cooling circuit (pump, cooler, and reservoir) for the turbo is also working great, the reservoir is only slightly warm to the touch after a bit of hard driving yesterday.
Oh and I got this

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Luckily he is going to do a remote since this will only require minor adjustments. Then when Hoss-05 is ready (his adaptronic is installed and working) we will both go up for a full session. I just need to save some pennies for the Adaptronic so we can go at the same time. If not I will just go up with him and have him fine tune my Cobb tune on the dyno again.
Thread Starter
SARX Legend
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From: San Antonio, Texas
Thread Starter
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From: San Antonio, Texas
Yeah we got a little cold snap and some rain but the afternoons are sunny and warm thankfully. I just wish i was retired so I could wrench more. I wish I had known, you could have come out to Coffee & Cars last weekend, it was the largest turn out ever, couple hundred cars at least and it was beautiful Saturday.
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Oh, I always have something going on. Right now I am just waiting on time a good weather to get some data logging time in so i can shoot them to my tuner. I want to enjoy it for a while and then I will install the Adaptronic and the components needed to make the switch to E85.
/thread
Yeah we got a little cold snap and some rain but the afternoons are sunny and warm thankfully. I just wish i was retired so I could wrench more. I wish I had known, you could have come out to Coffee & Cars last weekend, it was the largest turn out ever, couple hundred cars at least and it was beautiful Saturday.
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8-9psi, all is good so far. I'm running rich in certain ranges at high loads under boost and I am getting some spark blow out when the AFR's get to low 10's. And just over all it is too rich. But I already logged and sent them off to Steve, just waiting on him to shoot me a tune. I'm not surprised though after fixing the cracked manifold, actuator and the changes to the intake. Feels good to drive her for the past month though, big difference.
Nice work! FWIW with stock coils I never had any blowout all the way up to 17psi once I got the tune dialed in, and my highest load areas are in the 10's. With your BHR coils you should have no problem getting that to go away with the tune.
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Yeah when it goes rich, it's super rich, my AFR gauge is flat lining at 10.1. I mean I assume it is blow out, it just bogs. I got a new tune from Kan last night loaded but I have to drive out of town today so I won't get to test it
Last edited by 9krpmrx8; Mar 15, 2015 at 11:35 AM.
What plugs have you been running Slash ?
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Okay, I just want to say that Steven Kan at PRT Performance is a true professional. If you have a boosted RX-8 and you are not paying him to tune it then you are nuts. I received a retune from him last night and finally got a chance to load it and go play tonight. I thought it was quick before but now I feel like I truly know what a boosted RX-8 feels like, I was grinning ear to ear.
Last edited by 9krpmrx8; Mar 15, 2015 at 11:44 PM.
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But it is all good now, I still have a few slight rich areas when I get on the throttle abruptly in certain gears from a low RPM but I logged and sent them so I am sure the next retune will smooth those areas out and that will be it for now. Then when Hoss-05 goes up to visit him for the Adaptronic tune I will have him fine tune my car as well on the dyno.
Honestly I think the highest I took it to tonight was like 7400RPM, I didn't want to go to jail
I need to get her out in the country.
Last edited by 9krpmrx8; Mar 15, 2015 at 11:48 PM.


