Vincent7328
Active Member
Hey guys can help and guide me how to upgrade the 4g91 as you guys suggested for me taking 4g91 halfcut?
I heard some say that carb have a faster throttle response than EFI. True?
Hey guys can help and guide me how to upgrade the 4g91 as you guys suggested for me taking 4g91 halfcut?
technically speaking..... a carb would be instantaneous ... an efi on the other hand, can be slower or be exactly the same, really depends on how it was setup...
For starting, you should get everything working fine again. Some of the things that you can do is
1. Replacing all rubber hoses for the radiator piping
2. Replace oil seals like those at valve cover, crankshaft, flywheel and so on
3. Clean the throttle body
4. Change the engine mountings
5. Change new set of timing belt
6. Change new spark plugs
After all these, I suppose the engine should be working quite fine. I've actually done all these on my 17 year old 4G15.
Some of the basic things that you can consider to modify first on this 4G91 would be exhaust manifold(extractor) and air filter. You can consider doing a full piping for the exhaust system from extractor to muffler which I think you will need since stock 4G15 exhaust system might be a bit restrictive for your 4G91.
More serious mods after these will depend on you. Since you are interested in MIVEC, you can start to save up for a 4G92 MIVEC head. Reboring the block to accommodate larger 1.6 litre 4G92 piston and crankshaft is also an option. Larger capacity fuel injectors and fuel pump will also pair well with the mods. ECU swap and tuning is also needed at that time.
That fast on carb? I know if EFI using electronic throttle, it will be slower than cable throttle.
For starting, you should get everything working fine again. Some of the things that you can do is
1. Replacing all rubber hoses for the radiator piping
2. Replace oil seals like those at valve cover, crankshaft, flywheel and so on
3. Clean the throttle body
4. Change the engine mountings
5. Change new set of timing belt
6. Change new spark plugs
After all these, I suppose the engine should be working quite fine. I've actually done all these on my 17 year old 4G15.
Some of the basic things that you can consider to modify first on this 4G91 would be exhaust manifold(extractor) and air filter. You can consider doing a full piping for the exhaust system from extractor to muffler which I think you will need since stock 4G15 exhaust system might be a bit restrictive for your 4G91.
More serious mods after these will depend on you. Since you are interested in MIVEC, you can start to save up for a 4G92 MIVEC head. Reboring the block to accommodate larger 1.6 litre 4G92 piston and crankshaft is also an option. Larger capacity fuel injectors and fuel pump will also pair well with the mods. ECU swap and tuning is also needed at that time.
Weber carb mod will produce more power than EFI 4 throttle?
I heard some say that carb have a faster throttle response than EFI. True?

That fast on carb? I know if EFI using electronic throttle, it will be slower than cable throttle.
That is why I mention short intake manifold. Last time saw one 2nd Gen Prelude mod twin side draft weber with short intake and high cam. Pick up equal to old beemer 323i. Prelude only 1.8L....![]()
ok..so how about the 4g93?bcoz now i have 2 choice 4g91 and 4g93
like you already said if getting a 4g91..how about 4g93?is it the same thing i should like the 4g91?
Contrary to popular belief, injectors & fuel pump upgrades are not necessary until it is absolutely needed.
Bro., yours is carb to start with, so a weber mod is easier and cheaper. For a carb change to efi you will need complete wire harness.....
So all depends what you modding. Of course if already efi no point modding in weber, right?......lol


That is why I mention short intake manifold. Last time saw one 2nd Gen Prelude mod twin side draft weber with short intake and high cam. Pick up equal to old beemer 323i. Prelude only 1.8L....![]()
well... its literally pulling the cable, so as far as that is concerned, its instantaneous....
electronic throttles can be as fast, really depends on the car and its setup.... on some, older systems, basically its slow, on some of the newer cars however the car might decide that its smarter than you and prettymuch take control and do what it thinks is best for your fc...
I tried before revving an electronic throttle engine. The response feels weird to me. Like overly sensitive.
My friend who has a Evo X go to winding road then off those controls whatever and enjoy raw handling......lol![]()

haha when i changed from the old saga to my current car, yeah i felt the same thing... felt that the throttle response was very odd :proud: took a while to get used to it.... but now, i dont understand why i felt it was odd, dont even remember how it was diferent
Is there any more new cars for sale here that still uses cable operated throttle? Myvi maybe? Since the 1st gen K3-VE Myvi at my home is using cable. my foz already deleted the abs and airbag![]()
But why ABS?Which 4G93? SOHC or DOHC? The things to do with it will be similar to what I said about 4G91 minus the part about reboring the block to fit in larger pistons and crankshaft.
Now you are used to electronic controlled throttle.Is there any more new cars for sale here that still uses cable operated throttle? Myvi maybe? Since the 1st gen K3-VE Myvi at my home is using cable.
No fear for Takata issues.But why ABS?

ok..so how about the 4g93?bcoz now i have 2 choice 4g91 and 4g93
like you already said if getting a 4g91..how about 4g93?is it the same thing i should like the 4g91?
DOHC..and btw if im using 4g91 cc same with 4g15 1.5 my brake system need to upgrade?
DOHC..and btw if im using 4g91 cc same with 4g15 1.5 my brake system need to upgrade?
back to basic....and i didnt like how abs feels in action...not to mention so many sensors and things that can go wrong![]()
Your stock Wira 1.5 brakes is still sufficient for 4G91 DOHC. The engine isn't that much more powerful until you need better brakes to stop your car more efficiently.
Yours is which version? SF5 or SG9?
hmm... one thing i realize.... these guys who do this rarely put in cai's, basically some trumpets sticking out one side.... look as if it will suck lots of hot air.... till this day i dont understand why they do it this way

I think these twin side draft weber produces a very loud intake sound?

