Knocking after bolt on turbo

[yewly1990]

Hello there, just bolt on my car, its 1.5L almera.
Knocking was appear randomly after I bolt on turbo to my car.

This is some of the example case :

Engine start knocking when I travel 130km/h above with 0.6 bar and 4k rpm above.
But If I release throttle, boost drop and I floor pedal again, knocking gone, even reach 160km/h with max boost.

Below are my spec :
0.6 bar
stock piston / con rods
IHI rhf4
Pajero Intercooler (front mount)
Trust oil cooler
Hayden ATF cooler
unichip q+
1 extra injector

Tuning I was done in GT auto, first tuning, the knocking appear much more, specially when max boost, even in low speed.
First the tuner tell me I should use better fuel, so I change from 95 shell to 97 shell, after 2 full tank, it still appear, so the tuner told me to change to petronas 97 fuel, they got less knocking compare to shell... And knocking happen again, so I send back for retune with paying few 100 bucks.

Day of retuning, the tuner tell me, I should try change my intercooler to another position, and change my plug.
Alright, I change my plug from brisk to hks on that day, and retuning.
After retard the ignition timing at high boost, no knocking appear when tuning, he said this is the best setting.
But end up I`m still facing knocking rite now.

And actually, the wiring for my extra injector are weird, the electric are actually take from ignition coil, which sounds like not rite, but the tuner say it is fine to do that.

Any sifu can help me about this knocking case? I`m exhausted with it.
I will try mount the intercooler to lower cooler place which the tuner mention, but I dun really agree that the intercooler causing knocking... But still giving it a try...

I am quite worry that, maybe the unichip are not suitable for my car, some said I should actually change to engine management like haltech 500.

 

[vr2turbo]

Try Petron Ron97. I use before and work for my VR. I tried Shell Ron97 before and had to siphon it out or maybe you should try V Power Racing but not all station have it.
You mention changing the plugs, did you just the brand and type? What about the heat range try one number colder.....

 

[yewly1990]

Try Petron Ron97. I use before and work for my VR. I tried Shell Ron97 before and had to siphon it out or maybe you should try V Power Racing but not all station have it.
You mention changing the plugs, did you just the brand and type? What about the heat range try one number colder.....

The plug is HKS 50003 M40HL, 8 heat range, same plug with 2009~2010 GTR R35

 

[Allance 48]

how much air fuel ratio tat tuner set for u ?　（gd a/f for turbo car should b at 11.8 ~ 12.0 ) , or change other gd tuner n retuned ur car .

2nd removed ur thermostat can reduce water temp n knocking , bcos intercooler already block some cool air to cooling ur radiator water temp

3th hv u do heat shield for ur air filter ? since engine bay is very hot.

4th reduce the boost to 0.45 ~ 0.5bar if still got knocking problem

 

[yewly1990]

how much air fuel ratio tat tuner set for u ?　（gd a/f for turbo car should b at 11.8 ~ 12.0 ) , or change other gd tuner n retuned ur car .

2nd removed ur thermostat can reduce water temp n knocking , bcos intercooler already block some cool air to cooling ur radiator water temp

3th hv u do heat shield for ur air filter ? since engine bay is very hot.

4th reduce the boost to 0.45 ~ 0.5bar if still got knocking problem

I don`t know how to read my a/f ratio.

I will try remove the thermostat, no, I don`t have heat shield for air filter, I will try reduce to 0.5 if can`t solve the knocking.

 

[Allance 48]

got any dyno chart to share here

 

[yewly1990]

got any dyno chart to share here

 

[Waiora_ProTuner]

0.6bar can get almost double power? good then..

 

[vr2turbo]

I don`t know how to read my a/f ratio.

I will try remove the thermostat, no, I don`t have heat shield for air filter, I will try reduce to 0.5 if can`t solve the knocking.

For me, I would not recommend removing the thermostat. Engine need to run at a certain optimum temperature. Running cold can have more wear. Changing to a thermostat that open up at a lower temperature will be better....

 

[Jac83]

For me, I would not recommend removing the thermostat. Engine need to run at a certain optimum temperature. Running cold can have more wear. Changing to a thermostat that open up at a lower temperature will be better....

Agree with above said. Been there done that before and without the thermostat, the engine takes ages(around 8-10 minutes) to reach optimum running temperature from a cold start. Currently using a low temp.(76 deg.) Thermostat, takes only about 2 minutes to reach optimum running temperature.

 

[peterj]

Pls took the full dyno chart bos,there should me a/f chart and boost chart down below it.....and for lower boost like ur case lower then 0.7 bar,even it is turbo,tuner will set leaner,unlike higher boost car we set lower then a/f 12, low boost car can run leaner bit safely,and it save more fuel then high boost....

When during tuning,how is the weather?same as when u knocking otr,weather and temperature play lot of roles also,my tuner wont tune my car while rain or cold,cos if tuned cold,the power figure will be higher but when weather hot,the car will knock,so it will be safe if tune in hot condition,and look into the stock factory spec,almera stock compression is high,and i nt suggesting boost more then 0.5 for maximum safeness

 

[yewly1990]

For me, I would not recommend removing the thermostat. Engine need to run at a certain optimum temperature. Running cold can have more wear. Changing to a thermostat that open up at a lower temperature will be better....

Hmm, with the thermostat, currently the engine only take about 1~2 minute to reach optimum running temperature.

---------- Post added at 10:10 AM ---------- 6 hour anti-bump limit - Previous post was at 10:01 AM ----------

Pls took the full dyno chart bos,there should me a/f chart and boost chart down below it.....and for lower boost like ur case lower then 0.7 bar,even it is turbo,tuner will set leaner,unlike higher boost car we set lower then a/f 12, low boost car can run leaner bit safely,and it save more fuel then high boost....

When during tuning,how is the weather?same as when u knocking otr,weather and temperature play lot of roles also,my tuner wont tune my car while rain or cold,cos if tuned cold,the power figure will be higher but when weather hot,the car will knock,so it will be safe if tune in hot condition,and look into the stock factory spec,almera stock compression is high,and i nt suggesting boost more then 0.5 for maximum safeness

I have no idea how to read the a/f chart and boost chart.
But yes, I am worry about going high boost, stock compression is 10.1:1, I`m trying to get a 9.5:1 compression, but dunno where to get it.
Tuning was done in hot weather ( only dyno tune ), with bonnet open and big fan blowing the intercooler.
My knocking are randomly appear in afternoon even night cold weather.
Will change to EBC to lower to 0.5 if knocking can`t solve..
It actually din`t disturb me for daily driving, I dun drive that fast, but the fuel consume for city driving are extremely terrible rite now x_x.
From full tank NA 380, now 300. the first tuning are okie, 2nd tuning very heavy in fuel consume.

 

[stupidcar]

Hmm, with the thermostat, currently the engine only take about 1~2 minute to reach optimum running temperature.

---------- Post added at 10:10 AM ---------- 6 hour anti-bump limit - Previous post was at 10:01 AM ----------

I have no idea how to read the a/f chart and boost chart.
But yes, I am worry about going high boost, stock compression is 10.1:1, I`m trying to get a 9.5:1 compression, but dunno where to get it.
Tuning was done in hot weather ( only dyno tune ), with bonnet open and big fan blowing the intercooler.
My knocking are randomly appear in afternoon even night cold weather.
Will change to EBC to lower to 0.5 if knocking can`t solve..
It actually din`t disturb me for daily driving, I dun drive that fast, but the fuel consume for city driving are extremely terrible rite now x_x.
From full tank NA 380, now 300. the first tuning are okie, 2nd tuning very heavy in fuel consume.

One basic rule. A great tune will result in a smooth curve.

 

[^pomen_GTR^]

high rpm show too many spikes = something not really smooth like knocking...


so i think need to retard the ignition more.....reduce boost to 0.5bar....because a/f ratio is quite good already....


btw..did the bolt on turbo include thicker head gasket??? or the engine didnt do anything just put turbo on totally stock engine??

 

[yewly1990]

One basic rule. A great tune will result in a smooth curve.

Zero knowledge about tuning

---------- Post added at 01:51 PM ---------- 6 hour anti-bump limit - Previous post was at 01:49 PM ----------

high rpm show too many spikes = something not really smooth like knocking...


so i think need to retard the ignition more.....reduce boost to 0.5bar....because a/f ratio is quite good already....


btw..did the bolt on turbo include thicker head gasket??? or the engine didnt do anything just put turbo on totally stock engine??

DId tried thicker head gasket but checklight pop out.
I am searching for place to get custom piston now, some other sugguest me to look for interchange.
Still in progress

 

[KenDiriwan]

Thicker gasket is where you get lower compression because piston wouldn't reach that high for explosion. Did tuner explain why checklight came after using thick gasket ?

About inconsistent spikes at higher rpm, i do wonder his valve spring.

 

[vr2turbo]

DId tried thicker head gasket but checklight pop out.
I am searching for place to get custom piston now, some other sugguest me to look for interchange.
Still in progress

Without thicker head gasket the compression is too high for forced induction that is why knocking....

 

[yewly1990]

Thicker gasket is where you get lower compression because piston wouldn't reach that high for explosion. Did tuner explain why checklight came after using thick gasket ?

About inconsistent spikes at higher rpm, i do wonder his valve spring.

No, didn't explain

---------- Post added at 04:48 PM ---------- 6 hour anti-bump limit - Previous post was at 04:46 PM ----------

Without thicker head gasket the compression is too high for forced induction that is why knocking....

Any idea where to custom lower compression piston local?

 

[Jac83]

No, didn't explain

---------- Post added at 04:48 PM ---------- 6 hour anti-bump limit - Previous post was at 04:46 PM ----------



Any idea where to custom lower compression piston local?

Then I'll suggest either go back to your tuner and get him to better explain clearly why by using thicker gasket, the check engine light willl appear or find other reputable tuner who are able to do it for u. Obviously changing to a thicker gasket(custom gasket)to reduce compression is the most practical and economical in a bot setup. Custom the pistons will do the job too but it will burn a much bigger hole in your pocket and of course being a low boost setup, it will affect your engine response significantly especially during low to mid revs.

 

[yewly1990]

Then I'll suggest either go back to your tuner and get him to better explain clearly why by using thicker gasket, the check engine light willl appear or find other reputable tuner who are able to do it for u. Obviously changing to a thicker gasket(custom gasket)to reduce compression is the most practical and economical in a bot setup. Custom the pistons will do the job too but it will burn a much bigger hole in your pocket and of course being a low boost setup, it will affect your engine response significantly especially during low to mid revs.

Because the tuner are very busy, not able to layan me x_x..
I am using unichip, as I know, there is not much tuner around who able to tune unichip....
Puchong.... Ara Damansara...Sunway... and glenmarie only