When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
-You have spring pressure + pressure on top keeping the gate shut (which means the turbo spins faster makes and makes more boost)
-You have exhaust back pressure + pressure on bottom opening the gate (which makes the turbo spin slower so less boost)
If you tee the ports together they will cancel each other out and it will be eactly the same as spring pressure.
Not using a bottom reference will basically double spring pressure. So if you have a 6psi spring and it makes 6psi with the bottom port hooked up to the turbo, and you remove that reference line so the gate isnt connected to anything it should make about 12psi.
Try this before adding air on top.
Just a warning, if you put the reference line to the top of the wastegate without anything connected to the bottom port this means you are forcing the gate shut as boost increase so the turbo makes even more boost. Do not do this unless you want to blow up your engine.
I understand what you mean by running it with no reference. I'll try that.
But how can I add air to the top without hooking up the top port (which will create unlimited boost it sounds like)?
Good news is that I can make more than 8psi. Bad news is that a 30psi spike = kaboom
kidding. I took the reference line from the bottom and it now makes a consistent 12-13psi. Which is double the spring pressure as you said Richard. I was making 6psi with the exhaust connected and the MBC turned all the way down.
So now my question is, what do I do? Just get a stiffer spring and be done with it? Or is there a way to make my boost controller add more than the 2-3psi it's currently doing?
I've now got excessive blow by which by all I've read is a broken ringland.
With cutout open, seeing about 14psi. AFR was in the mid 11s, timing at 13degrees. Apparently that was too much and it had ~4degrees knock. She's dead
I'm sad.
On the bright side, with the cutout open it made a ton more power. Pretty gentle roll in in 1st and it spun pretty good. Never done that before. Guess I'll get to try it again in a year or two
Aug 12, 2014 | 02:49 PM
Cracked the ringlands, but didn't even break the ring 
