Standalone ecu for a st205, Worth it? Options

[skogs]

Hi, a workshop is changing the engine in my st205, and they have given me an offer to change the ecu to a haltech stand-alone and remap it for a total of about 900£ extra. Do you think this will be worth it? They will be putting in a Spec stage 3+ clutch while they're at it.

[pitcelica]

You need to understand that a full standalone tuning includes a lot of things other than fuel and timing :

-idle control
-warm up control
-cranking/startup control
-Accel/Decel control
-Etc...

A lot of these things can be tuned without the need of a dyno. You need to understand completely the Standalone ECU you are using along with the software if you want ot do it yourself. If you don't want to mess with all of it, send your car to a tuner and pay the price.

The only need for the dyno is to find power. You can find power mostly by playing with the ignition table. You can also find some power by leaning the AFR target at high RPM (around 12:1 AFR). This is where the dyno shine. For all the other things, you can do them on the street/in your garage.

Based on my tuning experience, it took around 3-4 hours to fully tune the ignition table (from 2000 RPM to 7500 RPM). The fuel table didn't need much tuning because I were able to tune it pretty nicely on the street (thanks to my wideband AFR sensor and the Megasquirt Tunerstudio VEAL software). The rate was 150$/hr for the tuner and the dyno (Dynapack 2WD).

My huge advice for the guys that are looking for a tuner is : ask them what kind of dyno they have : inertia or load-bearing. If you only want a WOT full power dyno number, than an inertia dyno can do the job. But if you want to tune part-throttle (this is where you can gain some fuel efficiency/MPG), you really need a load-bearing dyno.

A street-tuned car won't necessary blow his engine unless there is something clearly wrong with the parameters inside the ECU. Usually, you use a retarded igntion timing table and maybe a richer than it needs to be AFR target table, just to be safe. The engine will only lack some power and the fuel efficiency won't be as high as it should be, but at least you will be able to drive your car.

Sam

This post has been edited by pitcelica: Dec 3, 2013 - 2:30 PM