New wastegate actuator with great results
 

Just incase you guys didn't catch my other thread, here's an update on my setup.

Greddy kit with the 15g
Spearco bar and plate intercooler
Turbo Tony 2.5" downpipe
Megasquirt PnP
Supra 305cc injectors
Flyin miata dual-feed fuel rail
GT28 5psi wastegate.

So, with the stock wastegate, a lot of you know that you'll loose boost at redline and that the boost isn't exactly controllable.

For my setup, I had the original wastegate and I had a manual boost controller so that I'd have 5 psi at redline. This resulted in 6-7 psi at about 5-5500 and falling off to 5 towards redline. I also had an initial 5 psi at about 3500rpm.

With the gt28 wastegate, I had to use spacers to get it all lined up, but in the end, it worked out better than I hoped. Without the boost controller, it whips up to 5 psi at 3000rpm and is SOLID to redline. So, it helped with spool and holding boost ... sounds good to me!

awesome did you port the WG any?

ttiwwop

Nope, nothing else done except bolting on the new wastegate. I'll get some pics in a little bit. It's shimmed with old suspension washers, so I'll probably get some flak for that =P I'll be right back ...

Don't mind that "extension" connecting the rod to the wastegate. The stock unit was too short, so that extension with the washers made it fit =P

Attachment 215969

And a comparison between the greddy unit and the gt28 unit.

Attachment 215970

you're talking about the actuator - not the entire wastegate assembly - correct?

looks like it.

Yes, just the actuator.

Well while we are on the subject, how should one adjust the wastegate in order for the best performance for a MBC or EBC? I currently have mine pretty much tight as it gets and that gets me between 9 and 10 all the way to redline, but now I am spiking with the GM boost solenoid. Is it best to back it out a little?

leave it tight, adjust your ebc duty cycle to soften up before hitting target.

of course, overshoot (to a degree) is the shit. can you say TORQUE :bigtu:

seriously about that little bit of overshoot, it makes the car feel way faster than it really is. So how can I adjust it to just before hitting target boost when my dutycycle table is based on TPS and RPM? If you are talking about softening it up around 3500 when the turbo starts to be able to go good, it doesnt work because then if im goin 5000 rpm and hit it, it spikes there. What I need is the ability to tell the EBC to clamp down at anything below 7psi to get it started spooling and then let it breathe between there and 15psi. I would love to have a solid 15psi to redline but as it is its not happening.