My friend and I just finished installing a rebuilt TII engine into a 10th annie. It has been street ported and the turbo is stock, stock IC as well. There is an open 3 inch down pipe, so boost creep is inevitable until we port the WG.

The car has cleaned primaries and new 720's. The car has covered fewer than 30 miles on the rebuild so far, is very hard to start and runs rough down low. The engine timing is correct, we set it recently at 750 rpm.

The problem is:

At WOT in 2nd and up, car pulls hard at ~3500 rpm, ~9-10psi, all the way up until 5200rpm or so. At that point, the power noticeably dies off. With open exhaust and the afformentioned mods, the power should still be laying on thick until redline correct? I'm worried that I'm running lean at that point. Are there some things we should be checking? We just finished installing the engine so it's quite ossible we could be forgetting something. I think the turbo lags so badly because our twin-scroll isn't working, but I have no idea. I'm more worried about running lean at 10psi right now.

Do the secondaries engage solely based upon RPM or are they controlled by the metered bost as well? One thing to note is, right now the MAP is bad...it reads .87 volts at all times on the output signal. My understanding is that if it is WORKING, it will cut fuel to the rear rotor. But since it is not working, I think even after replacing it, I'll still have issues. This is with an Rtek 1.7 ECU installed, and we have the same problems when we switch back to the standard ECU. Also, isn't Rtek supposed to have FCD anyways?

Thanks,
Grant

 

RTEk DOES have a built in FCD.

 

Yeah, you may be running lean, but it is also a possibility that you have a boost leak. Check all your connections. sometimes leaks only show after a certain pressure. Almost tightly secure, just not quite. but I guess you would see the boost drop off drastically also. just a thought.

dpf22

 

Wait a minute. You just put in a rebuilt engine. You've only put 30 miles on it. Your already romping on it going over 4k rpm and boosting?

 

Yeah, I was just going to say...

Guess he's one of those don't-need-a-proper-break-in folks.


-Ted

 

No, boost stays above ~9 the entire time.

Yeah, I should break it in. We definitely got ahead of ourselves. I'm still hoping to get this issue resolved, and take a look at low speed driveability as well so I can break it in correctly.

 

Does MAP sensor have anything to do with how much fuel is injected, or is that solely the MAF?

 

FUEL FILTER, CHANGE IT.

lol

 

Hey man, that's not a bad idea. I'll see if I can swap it with one from another car, or run it direct.

Anything else? I'm thinking more along the lines of EFI, but you know...we've never seen this chassis drive before so it could be anything..

 

Is a narrow band O2 sensor and guage accurate enough for me to test the car with? Do I need to spend the big bucks on a wide band?

 

The rtek does not have a FCD built in,
it rather elimiates the coding in the ecu for fuel cut, which then allows it to keep reading boost correctly up to around 14.7ish psi when the sensor is maxed out

which is a big difference an FCD lies to the ecu which can cause timing maps to be off, when running past the fcd clamp psi.

 

Anyone else? Wide band vs narrow band? which should I buy?

 

buy a wideband and controlller car already has a narrow its the stock o2 sensor

 

wideband ONLY for in boost corrections.

without a wideband you will only be guessing that the engine is either lean or rich, if it was rich it would be belching black smoke and lean it would be lightly bucking just before power drops off and ping takes out the motor.

my advice is to lay off the throttle until you get a wideband and a piggyback fuel controller or pay a professional to tune the engine and/or diagnose the lack of power issue. if the boost is constant and it is lacking power then you really need to lay off of the power at that point and do it right or hope you have enough in the bank to pay for another rebuild.

 

MEH whatever.....taken from the ACTUAL site of Rtek....



better!?!?!?!

 

it also might sluggish b/c of the new rebuild the seals might not be seated all the way as the engine gets broken in it gains more compression

 

Good advice, but I think I am getting an Innovative LM-1 kit. I should then be able to see if I'm getting dangerously lean or not. Then I'll report back. My friend installed an FD fuel pump. I think this is kind of silly because that was what killed FD's in the first place, am I right? Does anyone know if the FD pumps would just die, or gradually decrease in pumping volume?

OK, so how does the TII administer fuel/control spark? If I'm boosting ~9-10 psi, does the AFM open wide enough to compensate for this? Should the stock ECU be able to handle this? Does all the MAP sensor do is cut fuel above 8.5 psi and retard the timing? How else does the ECU administer fuel? The FSM doesn't tell you crap!!

 

the FD pump is fine, good for about 280 or so wheel horsepower and reliable, more reliable than the walblow but some people have had good experiences with it.

the stock AFM is good for airflow up to 350WHP or so, i haven't seen one max out yet but then again i usually recommend a standalone well before 350WHP.. the stock fuel cut is 8.6PSI so you obviously have a FCD or you wouldn't even be able to hit 9-10PSI, it just clamps the voltage just before it hits the 8.6PSI threshhold, the timing should be safe enough still that you could push up past 10PSI with a piggyback controller. whenever doing upgrades to any reasonable extent to or past 10PSI tuning is required, guessing can only cause bad things to happen. with the mods you described it should not be running lean but you never know without a wideband to steer you in the right direction.

 

I don't have a fuel cut because the MAP sensor was defective. Hit 10psi with Rtek or Stock ECU.

Another thing, can a wideband even be able to be used in the standard bung? Isn't the EGT of these engines well above piston engines? Innovate says their Wide band shouldn't be used passed 900 degrees. Also, what do you guys think about just using a DMM hooked up to the standard O2 sensor to see if, at full throttle, the AFR is on the rich or lean side? I think the hardest thing would be to extend the DMM cables...

 

i use the stock O2 bung for my sensor and it has held up fine, EGTs can be 1300F or higher at the turbine but will start dropping drastically as it moves further away from the turbo, i would guess to say it would probably average around 1000F at the stock O2 sensor location.

narrowbands are useless for in boost tuning as i tried to make very clear earlier with the caps... narrowband O2 sensors can only tell you if the AFR is at or near stoich conditions, stoich is a reading of 14.7:1 AFR, in boost that is far too lean so even if you have the narrowband sensor pegged rich it could still be at 14.0:1 or leaner which is far too lean, a good number to shoot for is 11:1 after about 6PSI of boost and 11.5:1 by 4PSI tapering off to 13:1 at 0"Hg so you see the stock O2 sensor is useless for knowing what your engine is actually up against with the fuel curve.

 

Ah, ic. Good points. I need to do more reading on turbo tuning in general. I'm new to the forced induction scene. So you'd say it would be OK to run the LM-1 in the stock bung, for a little while atleast? I should be able to use the simulated output on the controller to plug into the ECU, so it still runs like a car with a narrowband installed, correct?

Thanks for the help so far!

 

According to Reted's website, the AFM is the sole device that's destributing fuel under load. Since this is a new chassis and engine to us, should I be checking the AFM (can you even??) or are they generally just plug and forget devices?

 

Could some my problem be caused by a bad/incorrectly adjusted TPS? Reted's site states that the TPS can cause "high RPM hesitation".

I've also have low speed driveability issues, and trouble starting the engine when it is cold. Couldn't hurt to check the TPS then..

 

well as many people stated you should let the engine properly break in before doing any high RPMs or even high RPM in boost loads, wait until you get the wideband before you do that.

cold start issues are fairly normal on rebuilt engines until they are fully broken in.