Terrh

iTrader: (7)

Got my FD running and on the road, yay.

Car is stock except for cone filters and a 3" exhaust. My alternator is overcharging and I am not sure if this is causing these issues or not, unfortunatly I had to drive it home so it got to see 16 volts all the way here. Don't worry though, it'll have a new voltage regulator in it tomorrrow if it's replaceable, and a new alternator if it's not.

boost is 10PSI in all gears below 4000rpm.

Above 4000rpm, strange things seem to happen.

Sometimes I get 10-11PSI and the car seems to be reasonably quick but nothing special. My opinion on this is probably jaded from my FC though.

Sometimes I get 4psi and the car is slow.
Sometimes I get 7-8PSI and the car makes a weird noise in the intake.. it sounds like something is opening/closing rapidly or something. It runs fine when it's doing this I should mention, and it's faster than it is at 4psi, but it still doesn't pull /hard/, or at least as hard as I'm expecting it to pull up high based on how it is down low.

While I /really/ like the lowend torque the car has I am still not sold on these twin turbos, it better pull like a ************ up high when it's fixed. So much complexity!

Terrh

iTrader: (7)

above 5000RPM in all gears the boost gradually bleeds off to about 1-2psi at redline.
I think it makes about 98HP at 5000RPM because it will only go like, 195km/h flat out, and my old 100hp civic would go 200 :P Don't let stock EF civic sedan's beat up on my FD!

3500-4500RPM sometimes I can get full boost, and sometimes not.

Below 4K RPM generally I'll get full boost instantly, but sometimes I'll only get 4psi or so and then after a second something "clicks" and WHAM 12psi. This comes on strong enough to blow the tires away in 2nd.

New alternator going in in about 15 minutes.

Ledfoot

iTrader: (1)

http://www.autosportracetech.com/RX-7/rx7stuff.htm

dgeesaman

iTrader: (7)

The intermittent stuff suggests solenoids.

I've never checked to see what 16v does to a solenoid, but since the turbos rely on solenoids for controlling the valves, it's worth testing again after getting system voltage to where it should be. It's only 2-4 overvoltage but maybe that's enough to damage a couple of them.

And never count out the boost leak. Some leaks, especially the well-hidden ones, can be intermittent. Every piece of rubber between the turbos, intercooler, and intake elbow need to be removed, remove the heat shields from them. Then inspect them, pushing/pulling to stretch open any cracks.

Dave

Terrh

iTrader: (7)

new alternator is now in, car makes a nice 13.8V at idle. Problem is identical.

It makes all kinds of groaning/whistleing/etc noises at various points while the turbo is spooling up as well... if I use maybe 20-35% throttle just as it crosses the threshhold into boost (about maybe 1psi) it will whistle loudly for 1/2 a second then be quiet again.

incase anyone didn't know, after you swap pullies an s5 alternator goes RIGHT IN, great way to get your car running quickly on a friday night with all the electrical shops closed. I'll be able to get the FD alternator rebuilt sometime this week, though really, this one seems to be just fine for now - I think it's 80A vs the 100A the stock one is, but I have no stereo at all and no demands on the electrical system aside from lights and the engine, so it should be fine.

Power windows/sunroof go /way/ slower at 12V too

dgeesaman

iTrader: (7)

I would start by changing out your check valves and looking for loose vacuum hoses. Even if they look good, it's important that they fit snugly on the nipples or else they will leak under vacuum/pressure.

I suggest doing the KOKO test at www.fd3s.net/boost_test.html and see that your vacuum chamber, pressure chamber, charge control actuator, and turbo control actuator are working properly.

When it's time to watch the CCA and TCA, you may need to remove some of the intake piping (CCA) and get under the car (TCA). Or creative use of a long handled peek mirror can work too. It helps to have a helper to turn the ignition on/off for you. When things are working properly, the cycling test will cause both actuators change position and *not move* until you turn the ignition the opposite way.

Dave

Terrh

iTrader: (7)

the link ledfoot posted helped a TON. Both vacuum lines were split that go into the boost chamber. I replaced and ziptied them on. There's a nipple right near where the one line attaches except closer to the passanger side of the car, on the vacuum spider that had NOTHING on it at all, and I could not find a line to attach to it, so I capped it off. Anyone know wtf it does? I'll post a picture of it in a minute.

The boost is still "funky" and is unfortunatly way too high.

in 1st I get 10psi till 4000 or so, then 7 till 5500, then WHAM up to 12-14.. it just seems like there's a lag.

In 4th gear I rolled on the throttle passing some people and held it at WOT till the secondary came online. Boost pattern was 10-12 below 4500RPM, 7psi from 4500 to 5000 and 15PSI above 5000. I let off very quickly when it reached 15PSI, it's possible that it could've crept further.

edit: can't post picture, person that took it for me is not online

So how can I reduce secondary turbo boost? Remove the pill from the WG line?

I'll do that testing tmrw as well.

RTS3GEN

If its the lower nipple where the vacuum chamber line hooks up near it's for the auto, isn't supposed to be hooked up. You have a series of problems. You have a line misrouted somewhere or a very small hole in a line(causing the whistling) which also is bleeding pressure from the chamber causing erratic switchover patterns. Impossible to diagnose unfortunately online, could be any series of solnoids and valves. As stated check your check valves to be sure they hold vacuum(just put an end in your mouth and suck on the end, one way air should not be able to pass if it does, heres part of the problem). Check also your Turbo control solenoid and Precontrol solenoid. You could bypass them altogether and just run the stock lines to both the precontrol and wastegate just cap off the bottom nipple. This will act as the boost control, unlikely though the PC and WG are the problem. Most likely the Chargecontrol solenoid(white solenoid under the manifold) or the Turbo control actuator under the turbos themselves.
Art

dgeesaman

iTrader: (7)

You say you have a "3in exhaust". Are you talking about just a cat-back, or have the precat, cat, and muffler all been replaced?

I don't like the idea of hitting 15psi, especially because you didn't explain your ECU and tuning. What boost are you supposed to be at? Inspect the lines coming to/from the wastegate actuator carefully - a leak in those lines will disable the wastegate and make for some dangerous and wild boost.

Removing the wg pill will reduce the secondary to 7-8psi (if there are no leaks there). It's a useful temporary measure.

Dave

Terrh

iTrader: (7)

I don't like the idea of hitting 15PSI either.

AFIAK, /everything/ is stock on the car except for the exhaust and the cone filters I replaced the airbox with (it was damaged in the crash).

The exhaust is a 3" downpipe/midpipe to a stock catback.

WG pill is coming oiut today until I figure out why there's so much boost. The car's been getting a diet of straight 94 octane as a saftey measure, but I still don't think I'd dare do a 3rd gear pull to redline at 15psi on stock /everything/.

Keep the replies coming folks, they've been super helpful.. about all I have time to do today is pull the WG pill, (gotta get my 10AE finished up!) but hopefully tomorrow I can spend the day working on it.

dgeesaman

iTrader: (7)

Sorry, I wasn't clear. Is there any kind of a cat in this exhaust?

Using stock boost control on a straight-thru exhaust simply doesn't work.

Dave

Terrh

iTrader: (7)

there is no kind of cat at this time

though it needs an etest so it's going to have one shortly I suspect, at least temporarily.

the stock muffler should provide a fair amount of restriction I'd bet.

I find it hard to believe that the TWO previous owners of the car never went WOT at high rpm in this car, though I could be wrong.

also, my dad did a 3rd gear pull to redline without me in it earlier today and it didn't blow up.... I wonder how much boost it saw *shudder*

which line /exaclty/ is the WG pill in, because I couldn't find it today and I took off a few lines that would look like they'd contain it.

Joe Geiman

I'm using the exact setup, 3" mid and down pipe with stock cat-back. No boost control issues whatsoever.

dgeesaman

iTrader: (7)

The stock cat-back is the difference. To me, 'straight-thru' means all aftermarket parts with no cats at all.

The dp/mp/stock cb is an uncommon combination, but it should be enough to keep the boost within reason.

The wastegate pill is not present in all stock turbos. Some have a restrictor built into the nipple at the compressor. https://www.rx7club.com/showthread.p...ighlight=pills

Dave

Terrh

iTrader: (7)

I didn't say "straight-thru" :P

What line is the WG pill in?

Terrh

iTrader: (7)

for some reason
it only creeps high in 5th now, no other gears.

Yay?

dgeesaman

iTrader: (7)

Yeah, I think I got cornfused because I was following 2 other boost threads.

Anyway, if you have a pill it's in the line between the wastegate actuator and primary compressor. If there is no pill, you may instead have the compressor nipple with a built-in orifice.

Dave