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over boosting issue

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Flameshades
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over boosting issue

Post by Flameshades » Thu Aug 22, 2013 9:40 am

Hi Guys

there is an issue with the car after the install that i'm quite sure is due to the car over boosting,
could any of you with a boosted solution (or more knowledge of a turbo set up on a rotary) please advise me where you plum the boost controller
into, even a diagram would be great (or pics of your bay that i can trace routes from would be ideal)

at the moment there is a Y pipe that T's into fuel pressure and then into the intercooler intake just before the turbo, then to port on the boost controller i think (need to check where the pipes were ran as i haven't looked) then actuator into the other side of the controller.

it doesn't matter what changes i make to the controller it doesn't change the boost created!

as always thanks for the help
Gary

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Re: over boosting issue

Post by Will66 » Thu Aug 22, 2013 1:23 pm

Boost controllers generally go between boosted side of the intake and the wastegate control.
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Re: over boosting issue

Post by BIG-Mal » Mon Aug 26, 2013 6:31 pm

The vacuum line on the snail of the turbo to the actuator fit your boost controller in there, there should be another vacuum line heading towards the engine you dont need that as your using the b/controller.

If you need to block any lines simly use a bolt and a clip to lock the bolt in place

Ps you'll be better off using an ebc "electronic boost controller" rather then any inline boost controller (only saying this as I dunno what system your using
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Re: over boosting issue

Post by Flameshades » Mon Aug 26, 2013 6:35 pm

Thanks Mal, i have a Greddy OLED profec, it has 2 lines coming off and one to the main unit its self,
i had it connected to the snail and also to the pipe just before it (off the air intake just before the snail)

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Re: over boosting issue

Post by ChrisNE » Mon Aug 26, 2013 8:06 pm

Should be the same as what I had in the Subaru.

The boost duty solenoid connects between the wastegate and the turbo snail, the T piece is installed to the standard fuel pressure regulator vacuum line and routes to the connection on the back of the controller inside the car.

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Re: over boosting issue

Post by Flameshades » Mon Aug 26, 2013 8:12 pm

i cant seem to find the FPR and by all accounts its in the tank on an 8......what i ahve Teed into doesnt seem to work very well.
the one i had on the S13 was fine as it was supposed to have a turbo and the routes were fine. but the 8 is a conundrum :)

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Re: over boosting issue

Post by ChrisNE » Mon Aug 26, 2013 8:51 pm

The fuel pressure side of things shouldn't have any effect on the boost itself, from what you describe the boost solenoid pipes are connected to the wrong place, it should look something like [urlw=http://i13.photobucket.com/albums/a300/ ... ebc9b4.jpg]THIS[/urlw], it may be that there is no way to connect the FPR to the controller on the rx8?

I swapped out the GReddy for an Apexi AVCR in the Scooby, it didn't have the FPR connection anyway...

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Re: over boosting issue

Post by Will66 » Mon Aug 26, 2013 9:06 pm

Image

That's the image that ChrisNE posted and :whathesaid:

I think the FPR connection is so the boost controller can jam the wastegate open if the fuel pressure drops considerably to prevent the motor leaning out on boost and killing itself.
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Re: over boosting issue

Post by Flameshades » Mon Aug 26, 2013 9:13 pm

thanks guys thats how i had it connected but the box of tricks wanted a connection too, so are we saying that we dont need to have anything connected to it??

that way it would just be pulling from atmosphere surly?

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Re: over boosting issue

Post by ChrisNE » Mon Aug 26, 2013 10:03 pm

Not sure.. although the connection to a standard FPR is just intake manifold vacuum/pressure... and AFAIK that's all it needs so it could possibly be tapped off anywhere on the boosted side of the intake.

what is the boost pressure with and without the controller connected? as you cant reduce the boost below the default pressure of the actuator, is the boost controller actually increasing boost at all and is the actuator actually working ?

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Re: over boosting issue

Post by BIG-Mal » Mon Aug 26, 2013 11:27 pm

Is your solenoid set up like
Actuator - com port
Turbo snail - no por
Manifold pressure - use the top small hose on the manifold

There shouldnt be any other vacuum lines needed ither then these

Then youve the display cables
Solenoid cable
Eartg
Ignition 12v

Youve then got the boost settings to sort "try not to use any self learning as ive only ever heard of these causing issues"

Also make sure you have the boost limiter set before playing around with any other settings 'it'll save your engine if ya mess the settings up'
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