Bambam7

OK, after blowing another engine due to detonation, I'm convinced my problem is due to the fact that I have no timing retard under boost.
The cheapest route is to use a TII ECU.
Here's what I'm assuming I'll need
ECU
TII pressure sensor.
That should be it! I know the AFM is different, but I've heard their compatible.. I also have the S-AFC if I need to compensate a bit.

Are the plugs the same? (these are s5 computers BTW)
If any of the wiring is different, it's probably easier to add/rewire a few oc the circuits than to buy and install a new wiring harness.


DO I need the knock sensor and retard box?? I'm under the impression that it's not even used under full throttle anyways.
Thanks!

hybridracer

As long as they are the same series they will plug right up.

1987RX7guy

iTrader: (3)

I would think you DO need the knock sensor and that stuff.

Bambam7

Does anyone actually know?
Thanks

1987RX7guy

iTrader: (3)

well from earlier in another thread I read that those components are what the turbo ECU uses to retard the timing so I would guess you need them. Based on that info.

hybridracer

You can get away without using the knock sensor. It would be good to get eventually but you wont need it right away, just like the AFM. The ECU's will match up, I know this for a fact as long as they are the same series. The knock sensor shouldnt be hard to find if you have a junk yard with some tII's in it. I believe its above the top spark plug on the rear rotor.

j200pruf

iTrader: (4)

Hey Bam, wouldn't be a lot less work and money to just install a MSD Boost Retard Box, or something similar?

jacobcartmill

iTrader: (6)

hey bambam7, have you run your car at the track? i've got alot of questions about your turbo 6port.

c-squared

He would need 3, one for the leadign and two for the trailing. Split timing is cut at WOT.

Bambam7

A used TII ECU is by far the cheapest option.
As for the knock sebsor, I beleive it is just used as a saftety provision under anything by WOT.
The N/A ECU doesn't have any programming to retard timing based on input from the pressure sensor, it actually advances it. The TII ECU takes input from the boost sensor and retards timing accordingly to reduce combustion chamber temps, and warding off detonation.

Bambam7

oops, meant to say the knock sensor is used at anything BUT WOT.

White_FC

No, sorry it does NOT advance the timming under boost, at all. The N/A preasure sensor will max out at around ~3-4psi, at least it does where I live (sea level...) and up until it maxes out it still retards the timing by the same percentage as if it was going from vacume to open throttle. After that max voltage is reached the timing stays constant.

I don't think that the fact the N/A ECU does not retard timing under boost is why your engine blew up. I'd be looking elsewhere. Unless of course you advanced the timing more than stock for an N/A.. but then it wouldn't be the computers fault I guess.

Makenzie71

You have an SAFC...just retard the timing a few more degrees and run a richer mix.

Bambam7

Jeez.. I want to hear your simple solution to world peace too! LOL j/k
AF mixture is rich. almost ot the point where it's hestitaint at WOT.
Still detonation.
I'm wondering what's going on....

White FC
Thanks for the education, that was news to me. Are you 100% sure that it actually REATRDS the timing as a continuation of the vac/tming curve? I thought it advanced it as vac approached 0.
Damn, I'm only running 7 psi right now. Since I'm a bit above sea level, the sensor should max out a tad higher than yours, like maybe 4 psi.... so why am I detonating at 3 psi??? Must be too much carbon in the chamber.

White_FC

100% sure.. at least that is/was the case on my S4 with the std. computer...
Definatly retards the timming as vac -> 0... like just about all cars
I tested it via an electic air pump I had lying around and timing light. Approached max volts at about 4.(something)v or other at just under 4psi.. and the timing was being retarded right until it got to that point, then just stayed the same.

And yeah well im not sure if you heard about my car recently but I was running 7psi with no worries at all, then the wastegate fell off and I hit 18psi! This is with the std comp for timing at the moment.
Shat a side seal though I think, just tore the engine out today, it didn't detonate though.. at least, not that I heard, and all the apex seals are good condition.