Forum » General Tuning Discussion » How does having a high stall converter affect tuning

How does having a high stall converter affect tuning

General Tuning Discussion

Discuss all things tuning in this section. News, products, problems and results. 

= Resolved threads

Page 1

Hi guys im still only learning about tuning atm and thinking of tuning my own lsx430ci, t400 ve commodore ute. Im undecided wether or not to tune stock computer and enjoy for a bit or go a full elite haltech setup yet. But im curious to know if there is anything diffiffernt that i would have to pay attention to or approach differently. Im using a tce 5500rpm stall. Its suited to 400hp of nitrous so will be a bit tighter maybe stall to 4500ish off the gas. ( wont be adding nitrous until a later date) Any feedback would be greatly appreciated

There's no real reason I can think of not to tune your combination on the stock ECU - plenty of tuners in the US and Australia have achieved great results with similar combos on HP Tuners or EFI Live. The only advantage that the Elite would give you is live tuning, but then with the factory CAN comms being removed, it's likely aspects such as the dash or A/C may not work (I'm not certain how involved the CAN bus is in the VE Commodore so research might be worthwhile before deciding).

A high stall simply means that you can't really do any tuning in the low end of the rpm range. When you apply throttle on the dyno, the rpm will rise to the stall rpm before any load is applied to the engine. With a 4500 rpm stall convertor for example, your useful rpm range ends up being around 4000- 7000. This means it's all but impossible to properly tune the low rpm areas of your fuel and ignition tables, however the reality is that this is also representative of the actual rpm/load ranges the engine will operate in on the street or strip.

When running a car with a high stall on the dyno, I try and raise the start rpm of my ramp runs to match the stall rpm. The reason is that if I start the run from say 1500 rpm, the engine will just sit at the stall rpm (4500) for several seconds until the road speed catches up anyway, and this massive slip in the convertor creates huge amounts of heat. Basically just tune the engine in the way it's going to operate.

Cheers for the quick reply. I was ti king of going the elite 2500 and haltech dash, and plan on running as many sensors as i can. Ive had nothing but dramas with this build due to faulty workmanship of other workshops and its cost me alot of money. Im wanting the flex fuel ability as well due to needing to use e85 with the nitrous. I can get it all at a reasonable price so that helps. Its probably not the ideal car to tune for someone that hasnt tuned before but being NA for a bit should be a bit easier im hoping. Im loving the coarses. Been a bit slack lately but ill get stuck back into them since the build is nearimg completion. Im unsure of all the capabilities that the stock ecu is capable of. But i intend to use the launch control functions and stuff as well if i go the 2500.

Do you just do the very light load / low rpm on the road then Andre? ie if you are just touching the throttle a little from takeoff the motor wont flash to 4500rpm. or even at cruise.

The Elite is a great option provided you understand that it's a pretty big job on a late model car like this. The fact you're going to go with an aftermarket dash will certainly simplify your installation and yes, the installation and your ability to add more sensors is definitely more flexible with an aftermarket ECU such as the Elite.

You can still do light throttle/low load on the dyno Viper. The areas you access on the road will typically be similar to what you'll see on the dyno. I always try to confirm the tune on the road anyway where possible.

With a high stall the rpm won't flare to the stall point as soon as you apply any throttle, but you can easily push through the lower rpm ranges without applying much throttle. You'll find that most of your cruise operation will tend to happen in a fairly narrow rpm band close to the stall rpm.

Cool cool, not done much with autos at was always curious

I think ill go ahead with the 2500 reguardless. Either stand alone and lose some of the luxuries atm or piggy back it once i understand it a bit more and regain half the interior function. Its not road registered at this point in time. So should be fine until i want to make another loom. And return it to street duties... I cant justify spending top dollar for quality gauges when the haltech/racepak dashes are cheap in comparison. So ill deffinately be getting one of them as well. Thanks for your feedback Andre. We will see how the stall behaves and approach it accordingly. No doubt you will hear from me again when its time to go.