Bamato

iTrader: (6)

So in a quest to make my boost levels more consistent and controllable, I'm going to make a few mods to the S5 stock turbo.

Currently I'm running open exhaust (and all the fuel and ECU mods to support it) and can boost creep up to 11 psi. However, it's not the safest way to achieve higher boost levels, and if it's too warm out boost levels top 5psi when the WG opens.

I have two projects to do at this point it would seem.
- Port the S5 wastegate to prevent all boost creep. Anyone have threads/suggestions on doing this? I've seen Aaron's S4 article, but the S5 is a little different.
- Replace the wastegate actuator with a 10-11 PSI one. Where do I find one that I can use with little to no modifications?

With that, I should be able to have consistent boost levels that I can control properly.

Anyone have any suggestions or see any holes in my theory/plan?

Bamato

iTrader: (6)

Found this article

http://fc3spro.com/TECH/HOWTO/KWG/kwg.html

So if I read this correctly, there's no need to install new flappers, just port it?

Bamato

iTrader: (6)

Can I just use any wastegate actuator? Or can the stock one be modified to accept larger springs?

schaft

iTrader: (1)

I'm going to.be.doing this to this winter and I have found out the easy way to do it is just hit the flapper with spray paint when its down so it'll leave the area under it clear then use the.clean area as a porting template. In other words if you port more then is in the clear area you need a bigger flapper, stay with in the bounder of the cirlce and you can.keep the stock on

freemanrx7

Yes. you can port the holes bigger. Also, you can get rid of (grind out) some 90* turns where the exhuast exits before flapper door.

J5sense

iTrader: (3)

i too plan on doing this during the snowy season. it looks easy only hard part is pulling the damn thing out. exsp when you had it out this summer.

LoLsmileyFC

iTrader: (37)

i believe you can use a stiffer spring on the stock waste gate actuator but even if the waste gate is ported i would still think the hole is still going to be too small for high boost apps.

it probably can only withstand a certain amount of lbs until it starts to boost creep. better go with a external waste gate if you plan on boosting high.

Molotovman

iTrader: (49)

No need to change the spring on the wastegate. Just get an EBC(electronic bost controller) or MBC(Manual Boost Controller) and hook it up properly.
There are plenty of threads on it to search for.

As far as porting the wastegate, just get a die grinder and one or two good carbide burrs. The carbide burrs are't cheap!
Follow that FC3S pro tech article and you'll be golden. It's easy.

Black Knight RX7 FC3S

iTrader: (7)

you would only need to change the wastegate spring ONLY if the exhaust gas is actually pushing the flapper door open. happens to a lot of hybrid turbos, especially if the turbine wheel is upgraded and clipped.
If it is pushing the flapper before your preset boost, upgrade the wastegate spring to something higher.

MaczPayne

iTrader: (5)

Here's what I did:

Ported the wastegate (opened up the entire paths, not just the openings near the flapper)
Electronic boost controller (properly adjusted).

Rock solid 10psi, and excellent response. It's easy to achieve this on S5's, and a lil harder for S4's.

Bamato

iTrader: (6)

It's my understanding that a boost controller has to work harder to maintain level boost with lighter springs on the WG.

Can anyone point me in the direction as to where to find a new WG spring? How do I go about replacing it?

Bamato

iTrader: (6)

Can anyone verify this ^^?

schaft

iTrader: (1)

It may be true on bigger turbos or on a higher psi, but fot a stock turbo 10 psi is very meak and the boost controller would have no problem at all controling the boost

Bamato

iTrader: (6)

Can anyone recommend an EBC on a budget? Or should I go with a MBC?

schaft

iTrader: (1)

What kinda budget you on? Cheapest ebc I've seen new is around 300$ on the otherhand mbc can be found all day long for under 50$ or can even be made.

Bamato

iTrader: (6)

I "could" afford spending the money on an EBC, but with so many projects on the FC going, and lots of vacation trips coming up, I'd prefer to keep it on a budget.

Are the MBC's a pain to set? Reliable? Pro's/Con's over EBC?

gameover2145

iTrader: (1)

MBC's just require patience to set. You have to do a run, pull over, pop the hood, adjust, do another run, rinse and repeat.

EBC's are obviously adjustable from the cabin.

The only real functional difference between simple EBCs (ones that aren't adjustable for gear, RPM, etc.) and a MBC is that an EBC uses a pressure sensor and a solenoid or stepper motor. The controller has the ability to keep the solenoid / stepper motor closed longer, eliminating the wastegate opening early and therefore preventing small amounts of exhaust gas bypassing the turbine wheel before desired boost. This improves boost response.

An MBC on the other hand is typically just a ball and spring valve, which will also open before the set pressure.

Bamato

iTrader: (6)

Settled on an MBC. Any recommendations on brand? I like the Turbosmart in cab ones. Seem like a good idea when I don't have a dyno to run on. Can make adjustments on the fly.

Bamato

iTrader: (6)

Ended up buying a Greddy Profec after doing my research. Where did everyone plumb these in on their S5? I know the stock system has an EBC near the rats nest, so I have to take that into consideration when plumbing. Should I T of it's line? Cap it?

Suggestions?

barkz

iTrader: (1)

sounds like youre not quite done

sharingan 19

iTrader: (16)

Your EBC should have come with instructions that clearly explain this (and if not they are usually easy to find and download online) But in the tradition of handholding that has apparently been established in this thread....Just run the input line from the nipple on the compressor housing, run the output to the stock wg and run the reference line to a trustworthy vac AND boost source. Most people T into the Stock pressure/boost sensor line.

Bamato

iTrader: (6)

I understand the diagram of where to locate the EBC. What I don't understand is what people are doing with the vac lines that the stock EBC are using. And after looking at the compressor housing and the way the vac lines loop from the compressor output, to the wastegate, and to the EBC on the rats nest, I've become confused somehow. Does the EBC for the S5 ECU still need to see some sort of boost signal?

If you don't understand what I'm asking or the source of my confusion (and if my confusion seems ridiculous to you), then I won't be offended should you choose not to offer help.

RotaryRocket88

iTrader: (7)

If you're using an an EBC, you won't be using the stock S5 turbo duty solenoid anymore. You can disable it. It's an electronic controlled bleeder valve that tees into the line from the compressor to the WG actuator.

This is incorrect. You're thinking of the typical bleeder-type MBC, which just bypasses a certain amount of air to reduce the pressure the wastegate actuator sees. The WG will still crack open before your desired pressure, but it will happen a little later.

A ball-n-spring MBC is either open or closed. Whatever tension you set it to determines when the WG will now see any pressure at all, which means it can snap open instead of gradually cracking open. I've used both setups, and the ball-n-spring setup (ala Gus Mahon: http://www.gusmahon.org/html/boostcontrol.htm) provides much faster spool-up.

Bamato

iTrader: (6)

Awesome. Appreciate it!