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Old 12-02-2007, 02:02 AM   #21
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Quote:
Posidon:
They Hydra is a nice box, I don't think I'd get rid of it. Or, if I were you, I'd sell it to me for $500. :-)
Your issue is likely the same as mine, and the way to tell is to run a hose right from the manifold* to the wastegate, bypassing the EBC entirely. If you're still getting overboosting, no computer in the world will fix it, aside from detuning the motor to the point where it won't make boost (i.e. generating only ~40 hp). You could try why I did, it seems to help a lot, really you could make something like I drew pretty easy with hand tools. The "correct" answer is a wastegate actuator with a longer throw - which FM said they haven't figured out how to do yet.

I might go to an external wastegate at some point, but I can't imagine my motor is that strong to need it. If I make an adapter like I drew, I'll make an extra for you. Once I get the distance right, it'd be easy to make a stack of them.
The funny thing is that I had this same problem without the EBC. The FM instructions say to lenthen the throw of the wastegate (without the EBC connected) until you only get 6-8 psi. I was never able to de-tune it to get these results. At redline it was getting up to 11 psi just on the wastegate. And since I had to lenthen the wastegate rod so much, it built boost UNGODLY slow. So I tightened it up to get some response, which helped, but the boost profile is still almost linear.

With the EBC turned on, I can't get the boost profile to max out and stay like it should. Jeremy at FM says for me to just tune the DC%/fuel map until I get the results I want. Apparently this cannot be done 'offline' and has to be tuned while driving. Since I can't look at my laptop and drive at the same time, I am having difficulties figuring out what I need to adjust.

Oh yeah, FM sent me a prototype wastegate to try out. Kudos for that, but the adapter didn't fit, the rod was 1/2" too short to be useful and it wouldn't have cleared their heatshield anyway.

This just seems like such a painful process. It should be easier than this...
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Old 12-02-2007, 05:51 AM   #22
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Originally Posted by posidon42 View Post
This just seems like such a painful process. It should be easier than this...
Yeah - get a wastegate with a longer throw. Adjusting the rod doesn't change the throw, it only changes the offset. You can do what I did, it seems to work (Though I'm a little worried my cheap bits had me pushing too hard on the flapper, it doesn't seem to move as easy as before) - it at least solves the real issue.

But really, look at the can BEGI uses on their kits - see how it's like 3 times the width? That's all travel, and that's what you need.

The answer FM gave me: Concider a more restrictive exhaust. I can't believe how poorly they are handling this kit.
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Old 12-02-2007, 11:20 AM   #23
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Consider a more restrictive exhaust!! OMG! I thought they wanted us to MAKE power, not kill it. Man this really sucks. If I had known then what I know now, I would have had all of you help me put together my own kit. There really isn't as much magic to putting on a turbo as I originally thought. Live and learn right...

So can I just buy the wastegate from BEGI and use that?
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Old 12-02-2007, 04:35 PM   #24
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Originally Posted by posidon42 View Post
Consider a more restrictive exhaust!! OMG! I thought they wanted us to MAKE power, not kill it. Man this really sucks. If I had known then what I know now, I would have had all of you help me put together my own kit. There really isn't as much magic to putting on a turbo as I originally thought. Live and learn right...

So can I just buy the wastegate from BEGI and use that?

Don't worry about it lol, there are many of us who bough kits of any kind and quickly realized from reading this site that a diy setup would of saved us both time and money in the long run.
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Old 12-03-2007, 04:25 AM   #25
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Agreed, they really are a safe way to get started. You pretty much gotta pay your dues somehow.

Well, I've been playing a bit. I chucked up my bolt in a latch and knocked off the threads where the arm fits on it, it really helps it not to bind!

But the weird thing: At like, 15-18 psi, the wastegate is great. It'd be pefect for a car running 20 psi of boost on a EBC. It's just totally the wrong thing for this car/kit.

I don't know how BEGI's would work, they are a friendly bunch, I'm sure they'd come up with something. I've seen a number of 1-10 dollar ebay stock ones that might be fine, they would all require some bracketry.

I forget to check how much boost I was geting on the way home, but I'll keep an eye on things and let you know how my set up is working out.
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Old 12-03-2007, 09:44 AM   #26
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BEGi uses a different wategate on their kits with a custom welded bracket....
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Old 12-03-2007, 11:17 AM   #27
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I recently did a WG can swap that required some new bracektry, in a quest to eliminate boost spike / droop (previously would build to 15, drop to 10 or 11). Sadly the results are not as impressive as I'd hoped. But if you wanna try it, perhaps something along these lines will allow you to fit the can of your choice: https://www.miataturbo.net/forums/sh...9&postcount=35
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Old 12-03-2007, 12:18 PM   #28
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I'm hoping to have a manifold built for my FMII which uses an external 35mm Watergate, but keep the turbo in the same place! Just trying to figure out the EGR port on my car. Not sure what the threads are on my 2000.

Later!

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Originally Posted by AbeFM View Post
Agreed, they really are a safe way to get started. You pretty much gotta pay your dues somehow.

Well, I've been playing a bit. I chucked up my bolt in a latch and knocked off the threads where the arm fits on it, it really helps it not to bind!

But the weird thing: At like, 15-18 psi, the wastegate is great. It'd be pefect for a car running 20 psi of boost on a EBC. It's just totally the wrong thing for this car/kit.

I don't know how BEGI's would work, they are a friendly bunch, I'm sure they'd come up with something. I've seen a number of 1-10 dollar ebay stock ones that might be fine, they would all require some bracketry.

I forget to check how much boost I was geting on the way home, but I'll keep an eye on things and let you know how my set up is working out.
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Old 12-03-2007, 01:58 PM   #29
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Originally Posted by mkulak View Post
I'm hoping to have a manifold built for my FMII which uses an external 35mm Watergate, but keep the turbo in the same place! Just trying to figure out the EGR port on my car. Not sure what the threads are on my 2000.
Darn big, that's what. :-) God I hate that nut, I get better at dealing with it as it keeps getting rounder, but it's a pita no matter what.

I was thinking of adding a wastegate to mine, external, but it's really overkill - all I need is something that actuates the internal better. If not, really, what's left of the FM kit worth keeping? The intake is just a cleaner, the IC set up is either rubber-and-adaptable (good, since it's too small, and if the turbo moves you could pick up their track further down the line) or garbage anyway. If you're doing all that, a bigger turbo might make sense - the LINK's are all crap. So, I guess I'd say I really like the turbo shield. :-)

I'm just worried, it's so tight down there, that if I added a external (there's room down bottom) it'd get in the way of all the water and oil lines. I replaced mine with hard lines from a DSM - which helped a LOT (they never break/burn/etc) but then you'd have to pull the whole turbo anytime you want to get to anything down there.
Quote:
Originally Posted by Joe Perez View Post
I recently did a WG can swap that required some new bracektry, in a quest to eliminate boost spike / droop (previously would build to 15, drop to 10 or 11). Sadly the results are not as impressive as I'd hoped. But if you wanna try it, perhaps something along these lines will allow you to fit the can of your choice: https://www.miataturbo.net/forums/sh...9&postcount=35
Oh! I'll check out that tread! What was your issue, btw? Do you run a MBC? You can make one for like $20 for a 'top end' one, and I get essentially no boost spiking most of the time. Also, a short spike isn't a big deal - a lot of factory cars run "overboost" for a short time (5 sec?) when you first step on it - then back off to keep from cooking things. Anyway, my MBC goes WHAM right up to maybe 1/2 psi over what I want, then comes back to it.

The bigger issue is when it's cold out sometimes I get a lb or two more than I want, steady state.
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Old 12-03-2007, 02:03 PM   #30
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Oh, that reminds me! As I said, the can had great travel when you got enough pressure, the issue is the spring is too weak. I was thinking a helper spring would help (your pic reminded me). Just putting a washer behind the pretension adjust nut and a pusher srping between the body and that should lower the pressure this thing works at - both springs are linear so it should only effectively lower the 'k' of the main spring.

I don't see why it wouldn't work, I might just try it. It's certainly the easiest fix of all, if the spring doesn't cook and detemper. Hmmm, I'm going to go raid my parts bin..
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Old 12-03-2007, 02:08 PM   #31
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Oh oh oh! Joe, where do you take your wastegate signal from? I had this same issue, if it's what I think it is.

How did you find the extra spring on the other wastegate worked?

Anyway, nice set up, I like it!
-------
Oh, ah, if you're spring is JUST that loose... yeah, I could see boost tailing off. I also think a bigger bleed hole in the MBC would help - I played with mine a lot when I made it to get it right. It wasn't my issue, then, it was where I took the boost signal. But that would help, then the spring shouldn't see so much pressure.

Last edited by AbeFM; 12-03-2007 at 02:17 PM. Reason: 'Cause I'm a tool and speak before I read
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Old 12-03-2007, 02:18 PM   #32
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Ok, replying to three questions...

I originally used a cheap DIY MBC. This is before I tried the helper spring. My boost was quite inconsistant from day to day- 10 PSI in the morning, 15 in the afternoon. And in general, it would build up to my set point (say, 14 for example) and then droop down to maybe 10 or 11. I hesitate to use the term spike, since that's not what it felt like.

I tried a TurboXS MBC, which is what I'm using now. There was a small improvement in consistency, but not much.

Then I put on the helper spring. Again, a tiny improvement. However this caused my base boost to be 9 PSI, which I judged unacceptable since my failsafe circuit on the WI system is to bypass the MBC in order to bring the boost down.

The can that I just installed is a Garrett part rated for 5 PSI. Running with no helper spring but about 3/16" pretension on the rod, base boost is about 7 PSI. Again, the problem with droop improved but was not eliminated.

Every step of the way, it seems like I make a minor, incremental improvement but never reach the goal of having boost go straight to a fixed point (say, 12 PSI) and stay there.

The signal is coming from the stock fitting on the side of the compressor housing. That's one thing I've not tried changing.
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Old 12-03-2007, 02:36 PM   #33
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Joe, check the post I made at the other thread:
https://www.miataturbo.net/forums/sh...9&postcount=44

This *absolutely* worked for me.
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Old 02-09-2008, 08:06 PM   #34
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Update!

Remounted the OLD wastegate actuator, it's throw is 80-100% longer!!


This alone almost got the boost under control..


Another view


Now, to the point


View of my two-position actuator thingie

Lastly, here it is on the car:


This DID put some limit on the boost. It's still pretty high, but seems to be ok. Turbo needs hoging, but it's a step in the right direction. I'll have to take pics of it "opperating" soon.

More pics at
http://abefm.smugmug.com/gallery/430...6S/1#252576736
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Old 02-09-2008, 08:47 PM   #35
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Golly, your wastegate isn't even hooked up! Problem solved.

Just kidding, of course.
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