Can anyone out there help with setting up a Greddy Profec B spec II boost controller.

i have a GT35R kit with synapse waste gate coupled up to the above mentioned boost controller. i have been given instructions from jason at rx7store on how to couple up all the hardware, so im confident thats all okay.

would just like some guidance, on what the basic settings of the boost coontroller should be. if any of the fundi's out there could offer some advice for a starting point, that would be great.

i would like to limit my max boost to 0.85Bar for now. my waste gate is currently limiting the setup, but it is overboosting for my present fuel setup.

the instruction manual is rather vague in my opinion, but then im a noob too.

thanks
GREG

 

Wait so what size spring are you running in your wastegate? If it's higher than .85bar you can't do anything to run lower boost than that.

 

its the lower of the two springs that comes with the Synapse wastegate kit..the instructions say that the wastegate comes fitted with the lower boost spring fitted in the unit and the higher boost spring comes as an extra in the box..i havent opened the wastegate up, i installed as is...i have the spare green spring in the box.

for now i have removed the screw in the top of the waste gate to ensure i dont overboost until my fuel upgrade kit arrives.

i have connected the boost controller boost source hose to ports A&B and the side port to port C..port D is left open.

finally then a noob question: the way i understand your post is that if the wastegate h a 0.85Bar spring, then the boost controller can do nothing to lower the boost to say 0.7Bar? does that mean the spring maxes out at 0.85Bar no higer, or allows boost to build up to a value higher than 0.85Bar.

i have seen 1.45Bar on the display as max peak boost

i hope im making sense of this.

regards

Greg

 

STOP BOOSTING YOUR CAR RIGHT NOW!!!!!!!!!!!!!!!!!!

You are going to blow your **** up because you don't know what you're doing. You aren't even clear how you have your boost controller is set up right now plumbing wise. How did you set up your boost control solenoid? You know it has to be configured for an external wastegate right? Draw a picture in MS paint of your setup or something.

 

i have stopped boosting the car...because of this fear..infact im not even driving it around anymore...so no worries there...im taking my time with learning all this stuff...and youre right, i dont know what im doing...but ill get there hopefully with your help and that of others on this forum.

i did send the car in to have the boost controller fitted and ive never been happy with the setup since the getgo..this is why i am asking for your help.

i have added a sketch of what the current setup looks like.
i also got this link from Jason on how to setup the plumbing.

http://synapseengineering.com/smf/in...54d&topic=97.0

thanks for your help so far!

GREG

 

I can't really speak much for Synapse stuff, so I can't help much in that area. I can say that that is the most confusing wastegate I've seen though. I run a Tial 44mm in my STi.

Either way, you need to know what pressure your wastegate will operate with no boost controller in the loop. Hi/Lo boost descriptions aren't useful for WG springs, you need to know a psi or bar rating. Whatever rating that spring is designed for that is the MINIMUM boost you will run at WOT, no matter what. You can run more to your hearts desire, but you'll never run less. It's the mechanics of the wastegate.

FWIW, if you can't find what pressure spring you have, you can hook a pressure source (manifold or turbo) directly to the wastegate, bypassing the boost control solenoid. By doing this you'll have the wastegate and the wastegate alone controlling your boost. I wouldn't recommend doing this though if you're not tuned properly.

 

first take the boost controller out of the loop, run the wastegate from bottom port to manifold. just to see how much boost the spring is.
by the way that is the most complicated wastegate i have ever seen! but your wastegate is run the right way.
start with all zero when adjusting boost. i also saw that the wastegate has an adjusting screw to raise boost, why use the greddy? it says the green spring is for 15psi, so stay with what you have in there now.

 

On the greddy boost controler, PSI cannot be lowered more than the
"stock psi"

Which is controled by the wastegate spring. If you have a 14 psi srping than when you set your boost controller to 0% set then it will do 14 psi. You need to 0% everything on your boost controler. to maintain the lowest psi your car can do.

 

Or just turn it off and run the spring. only problem is you might get some boost creep.

 

Thanks for all the help guys.

ive taken the boost controller out of the loop and gone back to the wastegate settings i had before installing the boost controller. so im back down to a safe 0.6Bar (9PSI)..FWIW ive used the A&C&D ports on this very confusing wastegate. yay, she is back on the road again!

when using just the bottom most port, as requested above it was boosting too much (+1Bar) for my liking so ill test that once ive got the right tuning for it.

at least now i understand why the greddy EBC isnt working? the combination of spring and valve seat is probably rated to a higher minimum boost than what im prepared to run at the moment. my tuning is okay for 0.8Bar (11 or so PSI).

thanks again for the help!!!

Nice car TWISTED, good choice in colour!!

cheers

 

Did you keep your EBC? or removed it?
I ask, because the lowest psi your HARDware can produce, which you said 9psi.

Then your EBC on full 0% set, 0% gain, 0% setgain. should give you your 9 psi.

ANd u might be able to 10%gain and get faster spool while maintaining the 9psi.

 

i have removed the EBC. the diagrams from synapse, require that port B is tee'd with A and then then connected to the solenoid. also the port on the top next to the pre-load spring needs to be plugged closed. when you do this the turbo is overboosting..to what value i dont know, cos im not prepared to risk it.

i played a little with the various settings for the vacuum & pressure lines to the wastegate and have found a setup that suits my fueling for now, the lowest setting i could get was just with port C&D tee'd into a pressure source, port A&B left open as well as the port ontop left open resulted in 7PSI . with A&C&D plumbed to a pressure source, boost is consistent at 9PSI and im happy with the that for now, would have like about 10 or 11PSI.

i will look for a tuner that can help with the greddy and set it up on a dyno safely, otherwise if i really struggle im going to stick in a HKS EVC like i have on my EVO.

regards

GREG

 

I have the greddy Manual.

For external wastegate setups:
On the valve unit.
The COM side goes to the external wastegate nipple.
The NC side goes to the turbo compressor nipple or good pressure source.