tip_tr_trig

[DOHCTOR_32V]

Hello, what is the correct value to help disable tip in retard with tip_tr_trig?

[dleach1407]

I thought the original setting is .75. I believe 1.00 is the correct setting

[DOHCTOR_32V]

Yes, .750 is commonly stock. I've seen / read both 0.00 (ZAO) and 1.00 (T4M2) otherwise. The docs I have don't specify. Maybe Decipha will post more info.

[decipha]

TIP_TR_TRIG = Torque ratio above which tip in spark retard is disabled.

From my rzasa def. Always best to crack open rzasa and cross reference parameters anytime you need more info.

this must be set to 0 or very low in all tunes to prevent tip in stumbles. This scalar overrides all other tip-in calculations and will always be used. It is recommended to set this to 0.15 for 87 octane tunes to prevent tip in knock.

in earlier strats TIP_TR_TRIG is word x/32768

TR_TIP_TRIG defines the trigger point in terms of change in air charge ratio beyond which a tip-in response will begin. A value of 0.9 will mean that an 11% change in air charge will trigger tip-in torque control (0.9 = 1/1.11).

[DOHCTOR_32V]

Thanks for that info. I'm now wondering why T4M2 has TIP_TR_TRIG set to 1.0?

[dleach1407]

Id like to know this too

[decipha]

thats cuz its nullified. I have the tip in spark max clip function maxed out

[DOHCTOR_32V]

Gotcha, the 63.75 value is shutting tip in retard completely down. So, TIP_TR_TRIG set has no effect if the Tip Max Clip is 63.75, right?

Doing some digging, I notice Tip Max is 63.75 and Tip Min is -0.01 in your RZASA, 87 octane, tune. TIP_TR_TRIG is 0.148. There are a few other tip in spark scalars that deal with RPM and torque ratio, but I don't see how tip in retard is functioning ATM.

I'm looking into FN2250 now. Could you please give an example of the settings / tables and maths used, for getting slight tip in retard using 87 octane in CBAZA? I've had Tip Max Clip at 63.75 on 93 octane, never adjusted TIP_TR_TRIG until yesterday.

[decipha]

correct

TIPMAX and TIP_MIN_SPK don't exist in rzasa, those scalars are just empty placeholders with no address.

TIP_TR_TRIG is whats enabling tip in retard on my marauder tune. RZASA uses FN704A the tip in max spark allowed function which Henry used to replace TIP_MIN_SPK in the eec-v.

yep no problem you can look at the stock t4m0 tune file as its setup for 87 octane.
TIP_TR_TRIG is set to .75 and TIP_MIN_SPK is set to 5 degrees.

So when tip in torque ratio is greater than 75% spark is clipped to 5 degrees to prevent knock with low octane fuel.

If you look on my marauder tune you'll see FN704A I have her commanding -3 degrees of timing on idle tip in to prevent knock. That's what it takes to prevent knock when you have a high compression engine ~10:1 compression running low octane fuel.

[DOHCTOR_32V]

Thanks, just to make sure I understand - that Tip Max Spark Clip of 5 degrees from your post above, will not allow spark timing above 5 degrees until torque ratio is lower than 75%? So if I want 8 or 10 degrees upper clip, I enter that 8 or 10 value in the Tip Max Clip?

Am I correct to assume that clip will work up to the spark value in the MBT or Borderline table, and any value higher entered into the Tip Max clip will just fall back to the lower value in the MBT or Borderline spark table?

Obviously a different torque ratio can be chosen with TIP_TR_TRIG.