derryck

Anyone know of a way to retard timing on the S? As many of you know, I've been working (I'm mostly just paying, my mechanic is doing the work) on a turbo kit for the S. We have realized as of late that anything much over 4 PSI with stock timing and pump gas seems to be causing detonation. As I'm sure we all know, detonation is bad and the two ways around it are to #1 retard timing or #2 lower compression. I have a different head gasket to lower compression but I'm trying to not have to crack the head open which leaves me with only one option... retard the timing. We're talking with MSD about some gadget they have but any help would be appreciated. This $4.40 a gallon for gas is killing me.

marcucci

AFAIK, the timing on the S cannot be changed except with a different ECU. The ECU controls timing and will not allow (or tolerate, if you could do it externally) modified timing.

I'd suggest contacting Hondata about retrofitting an older ECU, or to check progress for a "native" ECU.

RT

MSD did make a device at one time that spliced in between the crank angle sensor and ECU and retarded timing (variable delay) based on manifold pressure.

Good Luck!

koejing

I think it was the MSD Sebring (made originally for SC'd miatas). Check out the Bipes ACU: http://pages.prodigy.net/bipes/acu/ -- it takes the Sebring concept farther.

koejing

Wesmaster

Hmm, seems like this sounds familiar. Was this one of the problems that Ben had on his kit? Derryck, have you already talked to him about his "issues"? Might save some time.

Wesmaster

Tedster

Put a heater on the IAT sensor?

RT

Ted, that concept is not a bad idea, use the IAT sensor circuit to retard timing on call. (not with a heater though )

sylvainsf

Why not use a J&S Knock sensor? You can set it at a specific retard setting, and it will adjust further as it detects detonation...

koejing

Tricking the IAT sensor - that's a good idea! I wonder if the timing response is proportional across the entire IAT sensor output range or at some point the ECU sees a "too hot" condition and pulls a fixed amount of timing?

Using the J&S knock sensor is not really fixing the problem. You want to run enough advance/psi before detonation, not wait for it and then pull timing. Plus the car already has a knock sensor.

-koejing

sylvainsf

Like I stated before, the J&S let's you retard it AS WELL as makes changes on the fly..