Decat DP and IC upgrade, on stock tune - low quality fuel.

[Nick_CT]

So I have a 2016 Fiesta ST, bought it stock standard recently. I have now changed the intercooler to a bigger unit and also had a decat downpipe installed. The 'tuner' who installed the two hardware upgrades for me said that there wasn't much point in tuning the car for more power unless I want to run octane booster in every tank (which I don't).

I live in South Africa and our petrol is rated as 95, which I believe is equivalent to 91 RON in USA talk. So, not high quality fuel and his reason for saying a tune is not worth the money due to the low octane rating. He's a well respected tuner and it's not the answer I was expecting. Another tuner in town is convinced that even with stock cat and IC, the car could be safely tuned to free up some extra torque etc with our spec petrol.

Not knowing the technical details of tuning, I'm now wondering which is the correct answer. The car is definitely driving better now with the 2 hardware changes (stock tune), but should be able to perform a lot better considering what I've done. Or is the fuel quality going to ruin my party?

 

[Nick_CT]

Here is the spec sheet for our fuel, it does state 95 RON but I've definitely heard it compared to 91 in USA talk many times, I'm unsure why.
http://www.engen.co.za/Media/Default/Products/Datasheets/Fuels/Primax/ENGEN-PRIMAX-UNLEADED-2017.PDF

 

[stealthfist]

So I have a 2016 Fiesta ST, bought it stock standard recently. I have now changed the intercooler to a bigger unit and also had a decat downpipe installed. The 'tuner' who installed the two hardware upgrades for me said that there wasn't much point in tuning the car for more power unless I want to run octane booster in every tank (which I don't).

I live in South Africa and our petrol is rated as 95, which I believe is equivalent to 91 RON in USA talk. So, not high quality fuel and his reason for saying a tune is not worth the money due to the low octane rating. He's a well respected tuner and it's not the answer I was expecting. Another tuner in town is convinced that even with stock cat and IC, the car could be safely tuned to free up some extra torque etc with our spec petrol.

Not knowing the technical details of tuning, I'm now wondering which is the correct answer. The car is definitely driving better now with the 2 hardware changes (stock tune), but should be able to perform a lot better considering what I've done. Or is the fuel quality going to ruin my party?

There is definitely power to be made with an upgraded intercooler, which is regarded as a stage 2 upgrade. Stage 2 tunes commonly see 205-210whp/255-260lbft, with the lower figures probably being on 91 vs 93. Stock is 180/200. If your tuner can't tune the car, I recommend picking up a Cobb accessport and getting a tune from a reputable online tuner.

Sent from my HD1905 using Tapatalk

 

[CarGuy]

On a stock turbo you lose power when removing the catalytic. Congratulations..

Sent from my SM-N950U using Tapatalk

 

[RubenZZZ]

There is some power to be made. If anything, a tune will allow full boost in 1st/2nd gear (that alone really wakes up the car at slower speeds) and adjust how aggressive the throttle is. And if you like pops and backfires, that can be worked in.

I myself have a 91 octane tune, and I bet some more fun can be had now that I upgraded to a larger intercooler.


Sent from my iPhone using Tapatalk

 

[Dpro]

There is some power to be made. If anything, a tune will allow full boost in 1st/2nd gear (that alone really wakes up the car at slower speeds) and adjust how aggressive the throttle is. And if you like pops and backfires, that can be worked in.

I myself have a 91 octane tune, and I bet some more fun can be had now that I upgraded to a larger intercooler.


Sent from my iPhone using Tapatalk

You do not make power with a larger intercooler you retain power as your charge temps do not get as hot as to cause heat soak which you would lose power with.
As far as decatting the car goes again you do not gain power decatting our cars especially in stock form.
You can gain some power from a Tune and the tune benefits from the larger intercooler . It will not benefit a bit from decatting it.

 

[M-Sport fan]

Does South Africa get the EURO/BRIT versions of our car??

If so, would the Cobb AP everyone is suggesting even work on their MAF based engine management system?