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-   -   Just installed a diy turbo kit!!! Questions? (https://www.miataturbo.net/diy-turbo-discussion-14/just-installed-diy-turbo-kit-questions-10660/)

o.e.boost 06-19-2007 03:05 AM

Just installed a diy turbo kit!!! Questions?
 
Im new to the miata world but somewhat knowledgable in the boost world...i've done various homemade turbo kits for hondas and currently own an evo 8!!!...the setup on my 94 miata is a saab t3 turbo(pick up a while back at the junk), jgstools mani, evo 8 stock intercooler, vortec fmu, 2.5 dp, stock exhaust, and evo 8 fuel pump!!!...so far the setup is good and boost is a little slower than on my 1.8 ls integra back in the day but im fine with the setup...however there are times where boost is present but the car is not moving or possible lag from the turbo(surge)???...
my question is bipes acu unit able to fix the problem or how can you find out how much timing im running?

--i've been reading so much that i just couldnt find out how to find your timing...please help!!!

Braineack 06-19-2007 08:35 AM

are you saying, you have boost but the car doesn't feel fast?

too things, too much fuel & too little timing advance, most likely.

the timing marks are on the crank pulley.

http://www.miata.net/garage/timingmarks_closeup.jpg

and yes the Bipes will allow you to run more base timing advance and only pull timing when in boost, so you have increased low-end torque.

bripab007 06-19-2007 08:52 AM

Well, you need to figure out what the "problem" is before you can figure out what device/method will fix it.

You say sometimes "boost is present but the car is not moving." I guess I'll assume you mean, there's appreciable boost, but the car isn't accelerating as fast as you think it should.

Well, it could be that the Miata, with your particular setup, working properly, just doesn't accelerate as fast as another car with that setup would. Have you ever used that T3 turbo on another 1.8L engine'd car for comparison. On the 1.6L Miatas ('90-'93), even with a decent dallop of boost, the cars just don't really like to start moving until they come on cam around 3800-4000 RPM.

Another scenario would be that you're experiencing the lean running in closed loop mode before the ECU goes to open loop.

Another scenario might be your timing is way askew. You might be running too much or too little timing.

SloS13 06-19-2007 08:56 AM

have you hooked up a wideband!!! What are you using for fuel management!!!

Braineack 06-19-2007 08:58 AM

Brian you put that very elaglantly....I need to slow down when I respond :gay:

rotaryjunky 06-19-2007 09:24 AM

Does the car smooth out past 5K?

akaryrye 06-19-2007 10:00 AM

Dont Hondas have Map based ECUs and can accept boost with minor or no mods and be spot on as far as tune is concerned?

SloS13 06-19-2007 12:51 PM


Originally Posted by akaryrye (Post 124107)
Dont Hondas have Map based ECUs and can accept boost with minor or no mods and be spot on as far as tune is concerned?

yes to the first question. no to the second.

samnavy 06-19-2007 01:34 PM

$10 says we never see the OP again, but just in case...

YOU NEED TO TELL US MORE ABOUT YOUR SETUP!!!
Post a list of everything in your entire build and what the setting are. Include things not turbo related, like tires/brakes/suspension/clutch/etc... You don't even mention how much boost you're running.

I agree with the initial suspicion of timing... but also, do you know what a slipping clutch feels like. If you're running more than about 6psi on a T3, your stock clutch is not going to handle it. To the untrained, that can feel like "my engine revs hard, but the car doesn't pull anymore."

You need two things to tune with.
#1: Fuel pressure gauge. What is the Evo8 fuel pump rated to? What injectors are you running? Are you supplying enough fuel for the boost/power you've got dialed in? The only way to tell how much fuel you're pushing is with a gauge and through doing the math.
#2: Verify all of that with a wideband or dyno.

o.e.boost 07-01-2007 02:36 AM

sorry for the late reply guys...im sure its because i have little timing or no timing adjustments...i have yet to install the fuel pump which should be done by now but im getting lazy since i just came back from vaction...i need to order the bipes acu for some ignition adjustments but the wideband readings are going crazy when going from closed to open...basically the more load the more lean it gets. As of right now im having a problem with the internal wastegate not opening correctly, so i have to do some more tweaking to get it shy of 8lbs...just to let you guys know i really havent pushed the car all to hard(full throttle) but for the couple of times(i know im asking for it) the reacts the same as i said in post 1, which bogs when more boost is prestent...the car simply doesnt move when boost reaches 10lbs+...
--I really just wanted to know if ignition timing is the main culprit to this problem...
----my setup on the other hand is a saab t3 .42/.48 internally wastegated(that has proven to be a cheap turbo for a starter kit), jgstools manifold, greddy bov, evo 8 intercooler, 2.5 dp, 12:1 vortec fmu, and 2.5 intercooler piping...let me see if i can shoot some pics tomorrow for you guys:bigtu:

greddymx5 07-01-2007 07:45 AM

What do you have to add the extra fuel??
A pump is not going to help you much...
You need an afpr or an ECU to control the fuel...

As the car is not getting any extra fuel im sure thats the problem...

beerslurpy 07-01-2007 10:20 AM

He has a vortec fmu he says. I thought stock injectors were only good up to 100 psi and that would limit you to 8 psi of boost, no? If it is bogging as you transition into boost, I am almost certain you have too much or too little fuel from the FMU, probably too much. Look at your plugs/wideband and see if you are running rich or lean. Or just adjust the fuel ratio a little one way or the other and see which direction makes the problem better.

RemoteMX5 07-01-2007 11:50 AM

Get a WIDEBAND. You should not be attempting to do any tuning with out a wide band.

wildfire0310 07-01-2007 02:27 PM


but the wideband readings are going crazy when going from closed to open...basically the more load the more lean it gets
He says he using a Wideband and when boost get present it gets leaner and leaner.

First thing that comes to mind for me is 02 clamp issues.

o.e.boost 08-16-2007 05:22 PM

i've added a evo 8 fuel pump since then and i was assuming that the wastegate on the saab turbo is already set to about 8psi since i have not used/adjusted the rod. the boost gauge that i had took a crap!!!...i think the culprit of my setup is the boost actually shoots up to about 15 psi, causing it to bog in the higher rpm band...

o.e.boost 08-16-2007 05:27 PM

3 Attachment(s)
Here are some pics of my setup!!!!
Attachment 216029
Attachment 216030
the evo 8 intercooler
Attachment 216031

o.e.boost 08-16-2007 05:35 PM

i also forgot the mention that the logs with the wideband through a 1-3 gears are roughly 12.8-13.1 afrs with some knock present(the rattle heat sheild noise)...i have yet to have a timing controller like the bipes or msd but i will get the mspnp ems because i plan on adding bigger injectors...but does anybody know...or maxxed out the saab t3 45 trim?...i also plan on upgrading the turbo to the t3 60 trim turbo but i feel the saab will get me to the 250 mark!!!...:)

Red 90 08-16-2007 06:25 PM

First of all, if you don't have any timing controllers, you should really retard the overall timing to 6 deg BTDC or even lower. You risk detonating that thing.

Second, if your running at 10 psi boost, your stock fuel system will not handle that. How much fuel pressure are you running. I'm not familiar with the stock EVO fuel pump, but most OEM fuel pumps don't go beyond 90psi. You maybe running out of fuel when you bog.

Your setup looks quite nice, just get control of your fuel and timing control.

magnamx-5 08-16-2007 07:05 PM

The saab might make it. I would not run past 8 psi on stock fuel system with FPR in place, if you install the evo FP wich i asssume is a 255 hp then you might get abit more headroom. As the stock pump at the age we generally see can only hit 70-75 psi at the rail. Running a IC you are gonna need to get the bipes or drop the cash for a MS. Sorry If you wish to limit boost even further to live with the motor until the bipes gets there mock up a helper spring to prelaod the WG so it opens easier. You will spool slightly slower but it will allow you to dial down boost for agood while.

greddymx5 08-17-2007 10:19 AM

Are you running the oem fuelpump??
That is limiting the max boost.

The 45psi base pressure added 36 psi boost pressure equals 81 psi...(greddy limit, stock fp) So the 8psi on a vortech is not going to work...
You need a new 190hp walbro and a calibration set for the vortech. (probably a 8:1 or 6:1) As you need 6 psi fp / psi off boost.
The 12:1 vortech is completely shutting down fuel return...

Slowly advance timing til car knocks a little, remove timing till knock stops.

Add timing controller to get low rpm power back.


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