Thread: D2a TD5 - power/torque limit for the automatic transmission

A Stage 2 BAS remap (through tombie) is right on the edge. It has actually triggured the trans limit twice with the use of a really heavy right foot. Only other mod is the EGR removal.

Originally Posted by harlie

A Stage 2 BAS remap (through tombie) is right on the edge. It has actually triggured the trans limit twice with the use of a really heavy right foot. Only other mod is the EGR removal.

What happens when it's triggered? How do you reset it/get it removed? Is it as easy as turning the vehicle off and starting again or does it require a Techbook/Nanocom/electronic device thing?

I currently already have the EGR removal done, a unifilter air filter and the exhaust system has been modified to be more free flowing (i.e. all the original mufflers removed and replaced with free flowing ones). The vehicle currently has a BAS Stage 1 remap, so I might already have pushed the limit on the performance side of things then, as a stage 2 combined with my other modifications may have the effect of triggering the transmission limit too frequently for it to be worth it. The only other piece that I could probably look at then would be a replacement higher flowing intercooler which would benefit the air intake temperatures somewhat. My only concern being that if the intercooler is larger it may cause more lag which is not pleasant on an automatic transmission vehicle.

To reset it is a simple shut down and restart. While giving it everything you will get the M& S lights flashing, a chime and a severe lack of go. Both times have been overtaking with gear shift in D. pull back to 3 and let the converter lock before burying it and it’s happy and quick.
I’m still running as stock because it’s pointless throwing money at intercoolers and exhaust when the trans limit is already being hit. The only reason I can see to do an intercooler (with an Auto) is if you spend a lot of time way up north, or do a lot of heavy towing - essentially allowing the engine to operate cooler as opposed to gaining more performance. Intercoolers are a lot of $.

Originally Posted by harlie

I’m still running as stock because it’s pointless throwing money at intercoolers and exhaust when the trans limit is already being hit. The only reason I can see to do an intercooler (with an Auto) is if you spend a lot of time way up north, or do a lot of heavy towing - essentially allowing the engine to operate cooler as opposed to gaining more performance. Intercoolers are a lot of $.

I agree. As you point out, there are different ways to gain power. Some of those methods have other positive side effects, and both exhaust and intercooler are examples of that which should assist in helping the engine to run cooler.
Having a freer flowing exhaust should help to get the hot exhaust gases moving quicker out of the rear of the vehicle - Alive Tuning claim that there free flowing decat system can reduce EGT's by up to 100*.
Having a more effective intercooler can help to reduce engine temperatures by having cooler air entering the engine. However, at this stage I think I will not venture to upgrading the intercooler as I have concerns that a larger intercooler could increase turbo lag which is not something that I want on an automatic vehicle.
I don't know what effect the ECU tunes have on the EGT and engine termpatures. Do you find that you vehicle runs hotter at all now since being retuned?

Had the same questions late last year for Grimmy and with info from BAS, Slunnie, ZF auto specialists in Melbourne and TD5 Alive came up with the following feedback.

The std auto with extra cooling and decent oil and regular oil changes would handle a stage 2 map with upgraded intercooler etc and give approx 410+Nm and not compromise longevity. Anything over about 430Nm general consensus was

Once you want to ramp things up past this point you need to look at a larger torque convertor $$$ and upgrading the auto to 24 spline $$$, however this doesn't include 1st and 2 gear. Apparently the housing isn't long enough for this.

Personally didn't see the cost v benefit at this point.... Also was looking at a VNT as well.... I even thought about getting a manual D2 especially after I took a 110 out for a blat with the performance bells n' whistles

Hope this helps....

Originally Posted by pohm66

Once you want to ramp things up past this point you need to look at a larger torque convertor $$$ and upgrading the auto to 24 spline $$$, however this doesn't include 1st and 2 gear. Apparently the housing isn't long enough for this.

From what I understand the TD5 Discoveries have the ZF 4HP24 automatic transmission, while the older ones have the 4HP22, and so handle less power.

Originally Posted by harlie

A Stage 2 BAS remap (through tombie) is right on the edge. It has actually triggured the trans limit twice with the use of a really heavy right foot. Only other mod is the EGR removal.

Is your vehicle pre or post refresh?

Good Point - ours is pre update.

No change in Temp. We tested with nanocom (get the actual temp) before and after upgrade and there was no change in coolant temps.