90GSX-03EVO

iTrader: (27)

I just thought I would share some recent findings for everyone who is trying to decide which is a better for their setup. I really think that with using the Forced Performance high pressure wastegate actuator and the stock solenoid, we can basically make MBC's obsolete for stock turbo based cars.

I'm currently building up my car and while I'm waiting for my HKS EVC 6 boost controller to get here, I thought I'd try one of the Forced Performance high PSI wastegate actuator using the stock solenoid. Here's some results.


When the car was bone stock peak and redline boost looked like this:






Since then, I added a ported and coated exhaust manifold, Megan stainless steel O2 housing, and an AMS turbo-back exhaust with a high-flow cat.

The car has not been reflashed yet (installing cams and new front mount in the next week or so) and boost is now being controlled by the stock solenoid, stock hoses with the restrictor pills still in place, and a Forced Performance high PSI wastegate actuator.





Now, if you're comfortable with the boost taper of about 2 pounds between peak and redline, this should be a no-brainer for you. I'm sure the extra exhaust flow has skewed the data some, but most people tend to say that a widened O2 housing will cause boost spike. I don't see it, at all. At this point, I'm willing to say this would be ideal for those looking for a stealth boost control setup. I could play with this a bit more and turn it down (or up) some more. This was done at the zero preload setting on the wastegate actuator. For $99, I don't think I'll ever recommend a MBC to an Evo owner ever again.

Car: Evo 9
Fuel: 93 octane
Temperature: 20 degrees ambient on both nights as per local weather report.
All logs were done in 3rd gear.

Discuss

cij911

iTrader: (14)

This has been addressed in great detail in the Ecuflash section. The stock ECU can manage boost better than an MBC, but is a tad more complicated.

90GSX-03EVO

iTrader: (27)

That's just the thing. I'm not manipulating the maps in the ECU, either.

This was simply 2 12mm bolts, twist the actuator arm, clip it on, and attach the OEM vacuum hose.

ohEVO18

iTrader: (6)

i think im following ya on this, and it seems like a no-brainer, but thats exactly it, i dont have a brain whe it comes to this stuff at all...a lil too advanced for me

90GSX-03EVO

iTrader: (27)

I took off the factory wastegate actuator which is rated at 11 PSI. It's held on by two 12mm bolts and a cotter pin. There's one vacuum line that runs from the factory boost control solenoid to the wastegate actuator.

I put on a wastegate made by Forced Performance that is rated at 18 PSI. Bolted it up, connected the vacuum hose, and set the preload to what I thought was "zero preload" just as it shows in the video on Forced Performance website. Then I went out and drove the car. The first time out, I hit about 26 PSI in 3rd gear. I went back home and twisted the actuator rod out about 2 more full turns and then reconnected it. Drove it again and hit 22 PSI peak in 3rd gear. Went back home and gave it one more full turn counterclockwise and ended up with a 20 PSI peak that tapered down to 18 PSI at redline. I unscrewed it a bit more, and found that at 17 PSI, it holds almost 100% solid to redline with no taper, but boost hits later. Like around 4200 RPM's before you start seeing anything close to 17 PSI. I decided to turn it back up to 20 PSI with the 2 PSI taper.

mplspilot

iTrader: (7)

It's a no brainer in your set-up because you're actually missing the "C" part of the MBC or EBC.. If you know what i mean.
There's no boost control in your set-up except for adjusting the WG arm length. Which is fine if you're willing to go through the hassle and maybe burn and scratch your hands.
This ain't what the rod is for. That's what MBC's are for. Or EBC's. Or ECU based control.

PS. You say you won't recommend people spend $90 for an MBC, but you still had to buy an FP WGA...

90GSX-03EVO

iTrader: (27)

It's still running through the stock boost control solenoid, though, with the stock lines and pills all still in place.


I'm not knocking MBC's here. I've used them for years. I prefer EBC, however. What I was trying to show is for those looking at a stealthy mod (read: those guys out in California that have to pop their hoods every time the get pulled over) or for those who aren't really looking to mod a lot. Perhaps a "set it and forget it" type of modification and they don't want to hack up a bunch of factory hoses because one day they may want to return to 100% stock.

In other words, this part costs right at about the same price that a good MBC will cost you, yet you'd have to burn yourself while sitting on the side of the road trying to see if the car is modified.

vboy425

iTrader: (19)

wow you're holding 17psi till redline.

90GSX-03EVO

iTrader: (27)

18, not 17. And you're obviously not reading what I'm talking about doing here, or why it would benefit some people on this forum. Thanks for your wonderful thread contribution, though.


Also, if nothing else, 20 tapered to 18 (2 pounds of loss overall) looks a lot better than 18.3 tapered 14.2 (4 pounds of loss overall).

Mr Chef

I think some people are missing your point.

SPANKED

iTrader: (2)

Good info, was about to pick up a Hallman but now I'll research the FP wastegate.