Hi:

After fit aTD05FE turbo in my MY98 Impreza, I have had some problems:

1.- Some "boost surging" because of plug's gap (The gap of the Denso IK20 was adjusted from 1.1mm to 0.8mm)

2.- Boost leaks. The boost fell from 20 psi to 10@7000 RPM, The inlet hose was broken, so I changed it.

But...

I'm using profecB boost controller with two setting: low with 15 psi (1.01 bar) and high with 20 psi (1.3 bar). In the low setting, the car felt quicker than the previous TD04 15 psi, but with 20 psi, there wasn't a lot of difference (like other mates with VF22 by example)... well, at least from the "driver's feelling".

Last night I did some testing with a Gtech PRo and get (about 10° celsius):

220 HP at the wheels @ 15 psi
240 HP at the wheels @ 20 psi, falling to 17 psi @ 7000 RPM

Everybody who had tested my cars agrees the cars pulls very hard with 15 psi, but with 20 it should be better... so, it seems there is some problem...

Well, having this problems, I tend to think the fitment of the TD05 showed other problems in the car rather than the turbo it's broken (Nobody here in Chile uses TD05's only VF22, so everybody say "your turbo is not working"...) so my question is:

Where is the torque?, I have 2 theories:

- The engine is runing rich as a mad
- The exhaust is very restrictive.

These are my drivetrain mods:

- HKS SMF Air filter
- 3" exhaust (Custom made)
- Intercooler water spray
- Fuel pressure regulator @ 46 psi with vacuum line off
- Ssautochrome Equal lenght headers + Uppipe
- Walbro GSS 342 fuel pump

Thanks in advance

PD: Sorry about my english...

Regards from Chile

 

do you have diffrent maps for the diffrent boost preasures?

 

My guess is that with a standard ECU, you are running very rich, and the ignition timing is not all that good. The TD05 is better than a VF22 for power potential.

I think you need to find someone with a wideband AFR meter and check your AFR on full boost. If it's very rich you can try reducing the fuel pressure a little at a time, making sure you're not lean anywhere else (ie lower boost and no boost at all). You are really looking at having a new ECU to make proper use of these mods.

I would also make sure you're not getting any sort of misfire.

Paul

 

Try backing the 20lb of to about 17-18lb.when i put an exhaust on my ver3 sti it was runing 20lb and falt like crap so put my profect b (ebc) on and had a play and it falt best at around 18lb and made 267hp at the wheels on a g-tech pro. now the car has an ej257 block in it but im still runing it in on the factory ecu and it makes 222hp at the wheels on the g-tech runing 9lb, i'm also using a td05 with it witch i'll get hiflowed soon.

the air fuel ratios were 11 to 1 as soon as boost started getting up.

 

I'm guessing that by lbs you mean psi ?

Bob

 

I am running 1.4bar(20.3psig) and was getting missfire @ 6k with plug gaps set to 0.7mm with relatively new coils packs. Re-gapped plugs to 0.6mm which cured problem. As Paul has suggested - you need to get the car checked on boost with a wideband to verify the fuelling

Cheers

 

yip psi Bob

 

First of all, Thanks everybody for your help. I forgot post the AFR measured with my LM-1, these are below in the post. As Pavlo said, I was thinking in try by decreasing the fuel pressure, but it's already in the lower limit according the Subaru manual, so I am a little scared about this. One of my question is:

How much should I decrease the fuel pressure?, How should I check if the engine in running lean in low boost? What is the suggested AFR in this condition?

At the other side, I was thinking by trying with a set of NGK BKR7E with 0.7 mm of gap because it seems in high RPM's (over 6500 RPM) the car is having a very smooth "loss of power", but according to Delboy2 he regapped its gaps to 0.6mm, so:

What is the recommended gap for my application? Any bad effect by having less gap?

And the conceptual question, Why the engine could be running a bad timing?

Ahh, Sure I'm very aware about replace the ECU by a reprogramable one, but here in Chile you must pay a lot for the shipping and import stuff, so I need to save money first

Here are the AFR on full boost @ 20 psi. The left column is the timestamp and the other, the AFR's

14,582 22,3
14,664 22,39
14,746 13,27
14,828 11,23
14,909 10,3
14,991 10,1
15,073 10,05
15,155 10,05
15,237 10
15,319 10,01
15,401 10,05
15,483 10
15,565 10
15,647 9,97
15,729 10
15,811 9,97
15,892 9,98
15,974 10
16,056 10
16,138 9,95
16,22 9,92
16,302 9,97
16,384 9,92
16,466 9,95
16,548 9,91
16,63 10
16,712 9,98
16,794 9,98
16,876 9,98
16,957 9,95
17,039 9,94
17,121 10,51

Thanks in advance

Reagards from Chile

 

Hi,

I am having problems with poor spark on my car 1.3 bar on td05/06 it cuts out at about 6000. The plugs are new NGK pfr7b gapped to .5mm I was told to try NGK R7119-8 as they are apparently much better with higher boost

George

 

maby your ecu is seeing knock and is backing off the timing. your air/fuel looks rich but i still wouldn't run 440cc injectors at 20psi.

this is my dyno run with the ej20k, it was a bit lean as boost was just rising but never had any problem and was used like this for 30,000k's. this is just with a 3in exhaust, ebc and a 12lb flywheel.

 

Personally I'd set gaps to 0.7mm on the plugs and back the pressure off very very slightly at a time until I saw 11.3 to 11.5AFR on boost. You need to double check it drives okay off boost as well as on boost though.

What is the fuel pressure at the moment?

440s should be fine.

Do you have a knock link?

or can you make some detcans and listen for det?

 

Jolly, megrac

Now the engine is running 32 psi at idle and 43 psi with vacuum hose off. I don't have knock link... Sorry friends, but What is detcans? I have read that term in the forum but I don't know what is...

Thanks

 

detcans:a piece of steel fixed on rhe engine,a hoose to a listener and you can ear he knock

 

You're running very (very) rich. Are the AFR's the same whether you're running 20 or 15 psi? And what boost are you running at the redline on both boost settings? I suspect they wont be so dissimilar at 7k?

Have you measured air temps at throttle body? 60 degree TB temps at 20 psi, vs. 40 degrees at 15 psi would explain the difference.

Also, I can't remember how mine was, but losing 11 psi pressure when connecting the pressure line from manifold to FPR seems too much to me....that's .75 bar! Maybe someone else can comment on normal manifold vacuum at idle - but if it's too high, it would cause excessive charge temps because you're turbo is having to work so hard to create positive pressure.

Good luck!
Richard

 

If the FPR is a 1:1 Rising Rate Regulator then losing ~11psig(0.75bar) will be correct when connecting the Vacuum/Pressure back to manifold as the manifold pressure will also be @ -11psig(0.75bar) vacuum (Engine Idling) - so the base fuel pressure at atmospheric pressure (43psig) will reduce by the amount of +/- pressure applied to the FPR diaphragm
Do agree though that the AFR is very rich - Mine is between 11.4 - 11.6 AFR throughout Rev range when on boost.


Cheers

 

My point is that a vacuum in the manifold of .75 bar at idle suggests there is a restriction in the inlet path - I can't remember previous cars for sure, but it just seems too high. Anything higher than .3-.5 bar manifold vacuum at idle starts ringing alarm bells for me. Just found this http://bbs.scoobynet.co.uk/showthread.php?t=352777 - .3 bar vacuum at idle on an STi3

Richard

 

With my car Idling once hot with a calibrated gauge shows -10psig(0.69Bar) - Most In-car boost gauges are fairly innaccurate from what I have seen so there will be variations. The STi3 you are refering to is also a 2.5ltr

Cheers

 

my ver3 sti with an ej257 sucks 10.8psi at idle, cause theres a restriction in the inlet parth there is a closed TB

 

Hi:

The manifold pressure at idle is -18 psi, I think is correct... I haven't measured the Intake temps and, I think I'll test tomorrow. But I did other test, I tried by decreasing the fuel pressure at the rail in steps of 2 psi. The last test was at 38 psi (Subaru recommends 41 to 46 psi...) with 0 psi at the manifold and the AFR were about 10.7:1... I think there is some margin to decrease the fuel pressure even more...

Is not supposed the 380 cc inyectors should be outflow??? I remember Rich Wild's car who made 386 HP in stock ECU and inyectors...

I hope have some other numbers tomorrow.

Thanks!

 

I doubt it would reach -18psi in any circumstance as this would be beyond absolute vacuum which is not possible especially with piston engine, the most you would reach is ~-14psig @ Idle and this would barometric pressure dependant.

Cheers

 

The spark plug issues I do find odd considering the power, but I also noticed the misfiring at 6000rpm on the td05/06...........very strange indeed

The only cure was to fit racing 8 spark plugs - not the 7119-8's (I got these as a first pair) as they are way too expensive (at £145 for 4) and the alternative is much cheaper..... R7235-8's

From spark-plugs.co.uk for £66........ no stupid gaps to set (you'll see!!) and it sorted the probs

If you were running so rich you'd notice it anyway - with the amount of pops and bangs of the rich/unburnt fuel going down the exhaust!!

 

your boost gauge is messured in inches of mercury for vacume and not psi. mine reads 22 inches of mercury at idle whitch is 10.8 psi. so 18 in/mercury = 8.8psi

 

I have seen some curious flow results for the denso injectors, which suggest they actually flowed much more than 85% of the open flow whenat 85% duty cycle. This may be down to pressure fluctuations or something, but it certainly would explain some results.

If you are running 10:1 AFR and getting a misfire on boost, it's alsmost certainly going to be made much better by leaning it out to 11.2:1 AFR. I would guess you could be losing 20hp with the rich mixture.

Paul