Knocking after bolt on turbo

[Veloc]

That does not make sense because if got knocking means ignition is not proper hence by right the one with more knocking should give less power and the one with no knocking should give more power. This is the first time I hear such opposite happening.

Honestly for me, like I said in many other threads about fuel brands, I cannot tell the difference between them. They all seems very similar powerwise or FC wise. Or maybe I'm just not sensitive enough and my car is just too ordinary (too slow) to benefit for such difference.

Anyway back to the original topic, if want to try tuning the mapping, maybe can try visit RS Dynotune. A friend who installed SC kit for Mark X went there to tune and managed to get rid of his earlier knocking issue.

---------- Post added at 07:33 PM ---------- 6 hour anti-bump limit - Previous post was at 07:32 PM ----------



Yours is different league la, legendary 4G63T, already very well known for very sturdy turbo power ma!

Yup, I agree. When I had knocking issues in my VR on Ron95, the engine could not rev pass 4.5k rpm. Pick up was slow, mileage was bad.
For me all the while on Esso, now Petron. Main reason, station near my house and I don't have issues with the petrol. Then a friend who tried Shell pester me to try as he mention works for his Honda. I tried one tank of Shell FS formula Ron 97 and immediately I could feel the loss in power. Imagine it was so bad I went home siphon it out and poured them into my NA Hyundai.....

---------- Post added at 09:02 AM ---------- 6 hour anti-bump limit - Previous post was at 09:00 AM ----------



Sometimes you need to get to know them. Some of the bosses of shops I know, first impression by a new client they will say they look snobbish, etc., but after get to know them they are an ok lot. I think is human nature........hhahhahaha

I think my experience could be explained in this way...

Shell's petrol is very volatile and explosive. It combust fast and more readily. There was a video test to show the comparison of the combustion of malaysian fuels in the internet. I viewed it a few years ago. Please do look it up. It's kinda interesting.

So the very explosive nature give it high response. Just a light tap on the throttle and the car surges. Less throttle is required to accelerate and thus results in slight fuel savings. But on the other hand, the combustibility also makes it so much more susceptible to knocking. No matter how much I retard ignition, i can only reduce but not eliminate. I can live with that because it is not severe. I usually happens during a hillstart or WOT usually during hot afternoons. I can reduce that by adapting driving style.

For petron, its all vice versa.

I think for the example of your VR4, it is a different situation altogether because it is so much more higher performance. If it knocks, it will knock severely which will greatly limit the power. Also much more dangerous to the engine. IMO, slight knocking can be ignored and will not reduce power but severe knocking will definitely see power loss.

 

[vr2turbo]

Hmmm... but I try Shell Ron 97 and very poor response......My VR don't like shell......hhahahhahahah

 

[ixeo]

I think my experience could be explained in this way..

Shell's petrol is very volatile and explosive. It combust fast and more readily.

Shell RON 97 will be less volatile and explosive vs Petronas RON 95. As for Shell's RON 95 vs Petronas RON 95. I wouldn't know. I've not done a comparison or saw actual data.

You can take 2 Volkswagen with twincharge engines, 1 with Shell, another with other fuel, both RON 95 and compare on the dyno with AFR reading, and hook it up to an OBD 2 reader to see if there's any knocks. Then you'll have some way to authenticate how volatile and explosive...

Personally, on average of 5 tanks of fuel back to back, Shell delivers the worst fuel mileage versus Esso & Mobil (back then). For my car, same style, same route, same driver.

There was a video test to show the comparison of the combustion of malaysian fuels in the internet. I viewed it a few years ago. Please do look it up. It's kinda interesting.

Not sure what that proves, I'm no scientist.

So the very explosive nature give it high response.

Thus Shell would knock, especially in Volkswagen twin charge engines... during combustion cycle it would have exploded... it is possible.

Just a light tap on the throttle and the car surges. Less throttle is required to accelerate and thus results in slight fuel savings. But on the other hand, the combustibility also makes it so much more susceptible to knocking. No matter how much I retard ignition, i can only reduce but not eliminate. I can live with that because it is not severe. I usually happens during a hillstart or WOT usually during hot afternoons. I can reduce that by adapting driving style.

It depends on the car? Some cars show no difference even with premium high octane, while the same fuel shows improvement on other cars.
5th Gear - High Octane Fuels - YouTube

For petron, its all vice versa.

I think for the example of your VR4, it is a different situation altogether because it is so much more higher performance. If it knocks, it will knock severely which will greatly limit the power. Also much more dangerous to the engine. IMO, slight knocking can be ignored and will not reduce power but severe knocking will definitely see power loss.

By right, not supposed to knock at all.

 

[vr2turbo]

It depends on the car? Some cars show no difference even with premium high octane, while the same fuel shows improvement on other cars.
5th Gear - High Octane Fuels - YouTube

Clearly shows that non performance car will not gain anything on higher octane fuel.....

 

[Veloc]

Shell RON 97 will be less volatile and explosive vs Petronas RON 95. As for Shell's RON 95 vs Petronas RON 95. I wouldn't know. I've not done a comparison or saw actual data.

You can take 2 Volkswagen with twincharge engines, 1 with Shell, another with other fuel, both RON 95 and compare on the dyno with AFR reading, and hook it up to an OBD 2 reader to see if there's any knocks. Then you'll have some way to authenticate how volatile and explosive...

Personally, on average of 5 tanks of fuel back to back, Shell delivers the worst fuel mileage versus Esso & Mobil (back then). For my car, same style, same route, same driver.



Not sure what that proves, I'm no scientist.


Thus Shell would knock, especially in Volkswagen twin charge engines... during combustion cycle it would have exploded... it is possible.



It depends on the car? Some cars show no difference even with premium high octane, while the same fuel shows improvement on other cars.
5th Gear - High Octane Fuels - YouTube



By right, not supposed to knock at all.

1. I have not done a dyno test for this. It's all based on pure feel. So it can be subjective according to different drivers.

2. High knocking in in twincharged engines makes sense. Though I have never tried.

3. My friends who is using evo 8 reports the same finding as you. Best fuel economy by using petron and worst by shell. For me, it's vice verse. It all depends on cars i guess.

I can understand the possible factors why petron is better for turbo engines (most-not necessarily conclusive and exhaustive) while shell is better for NA (most-not necessarily conclusive and exhaustive).

 

[yewly1990]

1. I have not done a dyno test for this. It's all based on pure feel. So it can be subjective according to different drivers.

2. High knocking in in twincharged engines makes sense. Though I have never tried.

3. My friends who is using evo 8 reports the same finding as you. Best fuel economy by using petron and worst by shell. For me, it's vice verse. It all depends on cars i guess.

I can understand the possible factors why petron is better for turbo engines (most-not necessarily conclusive and exhaustive) while shell is better for NA (most-not necessarily conclusive and exhaustive).

I not sure, but I fill up a full tank of shell yesteday, knocking much terrible, and significantly of lost power on low end. And I notice only some shell station which have this problem, usually when I went to another shell to fill up petrol, does`t have this problem.
Previously using caltex and petronas, depends on which one nearby when the time I need.
I pour octane boost and significantly improve on both pinging and knocking.

 

[vr2turbo]

I not sure, but I fill up a full tank of shell yesteday, knocking much terrible, and significantly of lost power on low end. And I notice only some shell station which have this problem, usually when I went to another shell to fill up petrol, does`t have this problem.
Previously using caltex and petronas, depends on which one nearby when the time I need.
I pour octane boost and significantly improve on both pinging and knocking.

That Shell station very slow sales? Maybe stale fuel.....:hmmmm:

 

[yewly1990]

That Shell station very slow sales? Maybe stale fuel.....:hmmmm:

VERY good sales, I heard of rumours, some petrol station will actually add some unknown liquid inside their petrol.

 

[vr2turbo]

VERY good sales, I heard of rumours, some petrol station will actually add some unknown liquid inside their petrol.

Used to add kerosene but nowadays that is also expensive.....:hmmmm:

 

[yewly1990]

Currently just solve the problem, no more knocking so far after retuning in rs dyno, and better response too... The previous tuner din`t retard the timing enough... and a/f ratio not correct...

 

[vr2turbo]

Currently just solve the problem, no more knocking so far after retuning in rs dyno, and better response too... The previous tuner din`t retard the timing enough... and a/f ratio not correct...

Wow! you retard some more and get better response......

 

[yewly1990]

Wow! you retard some more and get better response......

Ya, in the dyno, power and torque show more on low end, obviously different in driving too

 

[Veloc]

Currently just solve the problem, no more knocking so far after retuning in rs dyno, and better response too... The previous tuner din`t retard the timing enough... and a/f ratio not correct...

You should let your previous tuner know. This is not a small thing. A tuner who doesn't know what he is doing can cause engine damage or catastrophic failure. Charge high but not well tuned. From your story previously, I had a feeling that you were being taken for a ride. Sounds familiar to me because I was once taken for a ride too.
Anyways, glad you resolved it.

 

[yewly1990]

You should let your previous tuner know. This is not a small thing. A tuner who doesn't know what he is doing can cause engine damage or catastrophic failure. Charge high but not well tuned. From your story previously, I had a feeling that you were being taken for a ride. Sounds familiar to me because I was once taken for a ride too.
Anyways, glad you resolved it.

I actually told him, but he claim that I just need to change my intercooler position, and change air filter position., Which is not the tuning problem.

The price I paid was below :
Rm2000 = 1 Unichip turbo module, 1 unknown brand map sensor, 1 unknown brand extra injector + tuning.
RM580 = HKS super fire racing spark plug x4
RM150 = retuning fees

I can`t say it is expensive, I dunno what is the market price of doing this, and also its SUNWAY, so maybe they got higher living cost so on, or maybe I pay the price for a professional tuning fees. I understand that tuning was an experience, and skill, so they actually don`t have a market price.
But I believe that, as a professional tuners, they should actually try to solve my problem, or give us any solution, but not bulldozing all the remarks back to consumers...

 

[vr2turbo]

But I believe that, as a professional tuners, they should actually try to solve my problem, or give us any solution, but not bulldozing all the remarks back to consumers...

That was what was mentioned earlier that when pay for tuning, it should be until it is complete. Not re-tune then charge, like that if his tuning is not good, you keep going back and you keep paying....
Unless it is like 6 months later you go re-tune then pay is ok.....

 

[^pomen_GTR^]

agree on that shell fuel now feels like no power and heavy fc..both on my n.a car and turbo...my n.a car benefits most fc saving and power using petronas 95 over petron 95...but my tubo liked the petron over petronas...maybe bcoz my turbo tuning was too rich...

 

[vr2turbo]

agree on that shell fuel now feels like no power and heavy fc..both on my n.a car and turbo...my n.a car benefits most fc saving and power using petronas 95 over petron 95...but my tubo liked the petron over petronas...maybe bcoz my turbo tuning was too rich...

I tried Shell older formula FS Ron 97, but since that was already not good dare not try the new V Power 97.....

 

[^pomen_GTR^]

I tried Shell older formula FX Ron 97, but since that was already not good dare not try the new V Power 97.....

fun
ny thing today i found out that my bike felt better at speed when using shell...

should give it another try...(same case before when petronas fuel suck big time)

 

[vr2turbo]

fun
ny thing today i found out that my bike felt better at speed when using shell...

should give it another try...(same case before when petronas fuel suck big time)

Once bitten twice shy, anyway Shell station further from my house......

 

[ixeo]

So yewly1990's problem fix already? Or the engine exploded due to insufficient fueling with full boost in closed loop.