4G93 performance enhancement

[steven1]

Hi gurus of car performance. I would like to seek your advice.

I currently drive a 4g93 N/A and have done the following to it:
1. Top overhaul (e.g. changed piston rings, use metal cylinder head gasket, skimmed cylinder head etc.)
2. Recently converted from auto to manual gear and changed to ultra light flywheel

With the above, the car is certainly driving a lot better. But of course, a car enthusiast's desire for greater speed knows no bounds. Therefore, to enhance torque performance, I was thinking of doing either of the following:
1. Change my present 15" OZ rims (which I was told while they are good, are heavier than most 15" rims) to some light alloy 15" rims.
2. Change my auto ECU to a manual one. I was quoted RM2000 to get this done plus all necessary tuning.

Question is, which of the above two options would be better, considering I only want to do one? What are the pros and cons of doing either?

Many thx for taking your time to read this and I eagerly await your speedy response.

 

[starscream]

im driving a wira using 15" spoon taiwan rims. the most noticeable thing after changing is the slight improvement during the first second of acceleration & improve in braking & manuverbility in corners of 60 - 90Km (most effective) but at 130+ you will feel the steering getting much lighter hence making control difficult (straight road is ok, but aggressive driving is harder.) heavier rims is easier to control in this range. you make the call, what u need most. RM2000 for management? im not sure but can you just use a VAFC & dyno tune it? its much cheaper, maybe around RM800-1100.

 

[Edisonkim]

hi dude.. i was driving top 1.8 below 1.6 with skim cylinder head engine rojak.. which i been using auto ecu.. now my previous car is auto.. then i change to manual.. after that i was change my gearbox to 1.8 mivec.. plus resize 1.6 tb body, resize maniful, n recenly upgrade to 1.8 sohc head as well as pont n polish the head the whole set is 1.8 head! i didnt change the ecu.. my mech say no need change for that.. i was also using 15 rim taiwan bsa brand.. with advance tire.. i think change ur ecu plus the wirelink i not so cheap dude.. maybe u can use the money to change to spoon rim or r3 rim also not bad.. or change to ur tire to low profile.. that will be advised.. ecu u change to manual one will got a bit different in the rpm speed limit n the fuel as well.. example ecu manual can up to rpm 7200 but ecu auto can up to rpm 6900 this one can cost the fuel also.. this is i was told by my mech but seen i mody a lot of thing in my engine turning is very important.. advised already told.. hehe u can ask more advise before u decided.. anyway have fun.. modi..

 

[ART///SPEED]

light weight 15 much better,hah ! rm2000 ? dont be,i got ecu 4G93 manual has rechip only rm1k

 

[SkYwAlKeR]

4g93 performance enhancement:
- bigger throttle body from perdana v6
- larger injectors from evo engines
- piggyback ecu such as safc/emanage/microtech/unichip
- swap to 4g92 mivec cylinder head with necessary wiring and ecu
- turbocharged it with low compression piston

 

[boyzone]

If u are look for better performance, u should go to 1.8 Mivec instead of top overhual.
Of coz, nothing is perfact in between light weight rim and heavy rim. Is depand on application.
Light weight rim able to provide good handling respone, pick up and braking, however, weak on high speed stability.

 

[spyderslr]

4g93 performance enhancement:

- larger injectors from evo engines

For NA setup, this will flood the engine lar.

 

[SkYwAlKeR]

For NA setup, this will flood the engine lar.

use adj fuel regulator and piggyback also cannot??...

den use injectors from v6 engine one lor.... or injectors from GSR geh...

can rite can rite??...

 

[spyderslr]

No point going thru so much hassle when a stock injector is sufficient, unless the car is heavily modified. Even if it is, it could still be an overkill. Not every parts from an Evo or bigger engine that you can salvage and slap on the engine will be good.

 

[boyzone]

changing on fuel injector will screw up ur stock air fuel mapping.. unless remap.
Btw, stock injector is still sufficient for those light mod engine.

 

[SkYwAlKeR]

ooo... yea... of coz slappin on larger injectors need piggybacks to remap the fuel so it wont overflow... but how much a piggyback can control the injector fuel flow i'm not sure lar....

 

[xinghonh]

u can use the evo injectors once u slap in a turbine to the engine

 

[steven1]

im driving a wira using 15" spoon taiwan rims. the most noticeable thing after changing is the slight improvement during the first second of acceleration & improve in braking & manuverbility in corners of 60 - 90Km (most effective) but at 130+ you will feel the steering getting much lighter hence making control difficult (straight road is ok, but aggressive driving is harder.) heavier rims is easier to control in this range. you make the call, what u need most. RM2000 for management? im not sure but can you just use a VAFC & dyno tune it? its much cheaper, maybe around RM800-1100.

Hi dudes, thx very much for all your advice. Starscream, yours in particular has been most useful and insightful to me.

Could you elaborate a bit more on difficulty in controlling at 130+? What happens when we drive aggresively, with light rims, beyond 130?

Could you also tell me about VAFC and dyno tune it? Very new to me.

Many thx

 

[starscream]

Hi dudes, thx very much for all your advice. Starscream, yours in particular has been most useful and insightful to me.

Could you elaborate a bit more on difficulty in controlling at 130+? What happens when we drive aggresively, with light rims, beyond 130?

Could you also tell me about VAFC and dyno tune it? Very new to me.

Many thx

Difficult to express the experience in words, the steering just felt extremely sensitive when corners at 130++kmh , you need more concentration to drive at high speed with light rims compare to heavier rims. But trust me, 15" is the best for cars below 200HP, unless you got something like a proton saga with vr4.

I don't have a VAFC, too many cases of car broke in liow, but its one of the simplest device to tune your A/F ratio, by running a dyno machine you would expect the tuner to give more fuel & optmize ratio through out the rpm range. The air/fuel ratio has been tune down from stock ecu to:
A) Reliability of engine
B) emission standard
C) Fuel efficiency
Pluging in with a VAFC from a "KNOWLEDGEABLE & RESPONSIBLE" tuner is up most important!

 

[steven1]

Another 2 questions for my car mod sifus

1. Is the 4g92 and 4g93 gear ratios the same?

2. I recently fixed a satria GTI 1.8 gearbox into my 4g93. Rpms vs speed are as follows:
a. 3000rpm = 85kmh
b. 3500rpm = 100kmh
c. 4000rpm = 120kmh
d. 4500rpm = 140kmh
Does this gear ratio seem right?

Many thx

 

[starscream]

not sure but my mivec is something like what you give, what is your km/h on 5th gear at 3000 rpm?

 

[steven1]

not sure but my mivec is something like what you give, what is your km/h on 5th gear at 3000 rpm?

5th gear 3000rpm gives 85 to 90kmh

 

[starscream]

guess it's a mivec gb, what is your gb code?

 

[steven1]

Didn't take the code number down. I got the gb off a mechanic who told me it's from a satria GTI. I also checked with a satria GTI owner who said the rpm vs speed seems about right.

Guess I just need to get used to the higher rpm.

 

[boyzone]

GTI gearbox is running with 4.322 FD, however 4.592 in mivec gearbox.
Btw, might have some offset in speedo meter.
For mivec gb, 5th gear with 80km/h is @ 3000rpm
100km/h is @3600rpm.