Unstable Peformance

hillies

Active Member
Senior Member

hillies

Active Member
Senior Member
Jul 23, 2007
46
0
1,506
Sometimes the car is very light and u can feel tht it's akinda powerful.. But sometimes it's heavy and sluggish.. What is the problem? THe peformance is akinda unstable I would say.. At times it's very powerful at times it's very sluggish... 4G13 engine only :(... BEsides, is there any tuning to be done? heard from a friend who told me about tuning the carb and exhaust can cause a misfire during gear shifts? is tht true? if yes, how do we exactly tune it?...
 

GT_AUTO

3,000 RPM
Senior Member

GT_AUTO

3,000 RPM
Senior Member
Oct 25, 2005
3,503
71
1,648
K.Trg
www.facebook.com
maybe ur a/c kick in,u feel sluggish le.about tuning carb,this u have to wait for
sifu skywalker.he's good in proton 1.3/1.5 carb.:).he can tunjuk ajar u.:).
 

SkYwAlKeR

Over 10,000 RPM!
Senior Member

SkYwAlKeR

Over 10,000 RPM!
Senior Member
Mar 12, 2005
10,139
300
5,183
ePoh ~ malacca
Visit site
me pulak??... ish...

no power coz aircond compressor kick in mah... blardy main culprit is the compressor... sucks away almost 50% of the power...

why u wanna tune ur exhaust to misfire??.. misfiring is a bad thing la.. aiyo...
u want better pickup or top speed??... done any mods already??... try advance ur ignition timing a little for better throttle response and pickup... top speed will suffer la... max u can go is about 140kmh only....

as for carburetor tuning, jz go to any workshop and ask them tune lo... 10bucks to tune the carb AFR and other stuff...

or u looking into more performance??... as in highcams, performance carburetor, port polish, bla bla bla??... budget??...
 

hillies

Active Member
Senior Member

hillies

Active Member
Senior Member
Thread starter
Jul 23, 2007
46
0
1,506
Ooo haha.. Thx 2 all d sifus.. well I've ald done the high cam thing.. but for now still ok ler... I've tried, nt a very long highway though, maybe 5km +/-almost reaching 160km/h, using 1.3 carb... is it ok? How come misfiring is a bad thing? looks very 'yeng' with a bit of fire at the tip of the exhaust hahahxx.. :)
 

SkYwAlKeR

Over 10,000 RPM!
Senior Member

SkYwAlKeR

Over 10,000 RPM!
Senior Member
Mar 12, 2005
10,139
300
5,183
ePoh ~ malacca
Visit site
Ooo haha.. Thx 2 all d sifus.. well I've ald done the high cam thing.. but for now still ok ler... I've tried, nt a very long highway though, maybe 5km +/-almost reaching 160km/h, using 1.3 carb... is it ok? How come misfiring is a bad thing? looks very 'yeng' with a bit of fire at the tip of the exhaust hahahxx.. :)
ooo... fully modded adi... fuhyoo...
what cam duration u use??... if above 272degree, usually u will suffer abit at low end... using adj campulley as well??... if still sluggish (even with aircond off), try get a proper mech with know-how tuning on highcams and so on... highcams, valve/tappet adjustment, campulley and carburetor all need to be configured to work with each other well to get the best out of ur highcams...

misfiring happens when spark occur when ur exhaust valve starts to open... this usually occur when ignition timing is not correct couple with high duration camshaft...
but in some cases such as turbo cars, misfiring is purposely induced to reduce turbolag during deceleration... when air/fuel ignited during the opening of the exhuast valve, the detonation will push the turbine to spin fast even under deceleration... yes, this will damage the turbine in long term... but track cars with time attack in mind wouldnt care much about reliability... all they want is fast lap time...
 

boyzone

2,000 RPM
Senior Member

boyzone

2,000 RPM
Senior Member
Mar 13, 2005
2,669
38
3,148
go for 13 or 14 inch light weight rim, might help u to improve ur pick up.
Btw, is it worth spand some $$$ go for 4g91 / 92...
economy and reliable instead of spand a lot into 4G13.
 

tofu_manic

1,000 RPM
Senior Member

tofu_manic

1,000 RPM
Senior Member
Jan 11, 2007
1,342
91
1,648
sifoo sky has spoken! :adore:

if not mistaken the aircon sucks away more than 10 HP according to one guy who dynoed his 4g15... :sheep:hehe
 

seanlee

Known Member
Senior Member

seanlee

Known Member
Senior Member
Jun 30, 2004
382
1
3,018
if you have done high cam..also so on...
bring your ca to DYNO...so that you can se the graph weither it tune the proper way also the misture of A/F is it correct..
this is the proper way to know your car tuning...

also like sky said Mis firing..is not a good thing to do...YEs is look Yeng and Cool....but hell if you afford to get another new engine in short time...then be with it..
if Missfiring look cool and will not harm the engine...i think alot people in straight ou looking at already have liao..before you know...
 

DDOLINK

Known Member
Senior Member

DDOLINK

Known Member
Senior Member
Mar 16, 2006
209
0
1,516
wahhh sky..now become sifu edi arr..btw, no need to on aircond la when u want to speeding..try to tune ur carb..tune using the CO2 machine and find a reliable mech..i have tune my carb after doing my exhaust setup now the performance and fc is better..balance is what i meant
 

hillies

Active Member
Senior Member

hillies

Active Member
Senior Member
Thread starter
Jul 23, 2007
46
0
1,506
ooo... fully modded adi... fuhyoo...
what cam duration u use??... if above 272degree, usually u will suffer abit at low end... using adj campulley as well??... if still sluggish (even with aircond off), try get a proper mech with know-how tuning on highcams and so on... highcams, valve/tappet adjustment, campulley and carburetor all need to be configured to work with each other well to get the best out of ur highcams...

misfiring happens when spark occur when ur exhaust valve starts to open... this usually occur when ignition timing is not correct couple with high duration camshaft...
but in some cases such as turbo cars, misfiring is purposely induced to reduce turbolag during deceleration... when air/fuel ignited during the opening of the exhuast valve, the detonation will push the turbine to spin fast even under deceleration... yes, this will damage the turbine in long term... but track cars with time attack in mind wouldnt care much about reliability... all they want is fast lap time...
Ooo.. well.. my car where got fully moded ler lolx.. just minor mode oni ler sifu... exhaust all oso din change yet.. just change centre bullet oni lol... all stock hahaxx....