underpower 1.8 mivec

[killerbee78]

I own 1.8 mivec few month after transplan it from 4g93.silver top,lsd gbox,mivec wiring+ecu 4828,4g93 piston,work fuel regulator,trinity clutch n ngk cable plug.any suggestion to up its power or my car not properly tune.no management yet.plan to install vafc.a lot of people don't recommend mivec piston due to 1.8 blok.my block is dohc

 

[deacon]

Get stock 4G92P pistons. Balance your crankshaft.

 

[killerbee78]

What is balance crank shaft?what to do?still newbies

 

[deacon]

Balancing is when someone takes apart your bottom end and makes sure all the parts tied to the crankshaft i.e. pistons, conrods etc etc all weigh the same amount. This way increasing the rotational speed of your engine. In simple terms, makes your engine more efficient at revving. When your car is more efficient at revving you get improved accleration and your engine can now make HP at a higher rpm.

Balancing also creates less vibration which also helps your engine recover lost HP too. But don't expect much increase, maybe 3 to 5HP at the most - not at the wheels.

For your information, vibration is caused by having one or more parts in your bottom end that weigh different amounts.

A 4G93P crank is fairly slow. Balancing it will make a big difference especially since the Mivec head requires the crank to spin at a higher rate to achieve more power.

 

[Shinjite]

Should go MIVEC pistons

 

[^pomen_GTR^]

yep...

u should use mivec piston...(higher compression ratio)..and that would probably restore back your engine performance...

 

[Enslaved]

Too high a compression and you might experience pinging on hot days (which is always in Malaysia). Make sure it's tuned properly but without a good headwork and tuning, it's not really advisable to go too high a compression. You will also need high lift cams to really get the power from the hi-comp engine. Stick with your 1.8 pistons and you can have more leeway with the ignition timing i.e. can go higher. All the best.

 

[amad108..]

why not use e-manage bro? vafc maybe insufficient..
e-manage also has wider range tune compare vafc or safc..

 

[oly]

just change to mivec piston and 0.4 m metal gasket and u will feel the power back...no need to balancing ur crankshaft...

people talking here seem like they dont know that mivec need to use hi comp piston...and 4g93p piston is almost flat...oni got around 1mm bump oni...how to make hi compression...and yes...my mechanic has done many mivec 1.8 and never use the 4g93p or 4g93 piston...average comp for 1.8 mivec is around 13-16...the best if u can achieve up to 17...

 

[deacon]

17 per cylinder with our fuel... i'd like to see that, especially if you are using a thinner metal gasket.

 

[^pomen_GTR^]

17 per cylinder with our fuel... i'd like to see that, especially if you are using a thinner metal gasket.

maybe he means 17psi using compression test gauge?

 

[deacon]

I don't get it. 17 overall compression ratio versus a compression test gauge 17 would still be really high. This would be 17 static no? Care to explain the finer points and details?

 

[oly]

normal 1.6 mivec will go around 16 psi using compression test gauge...

 

[deacon]

... still don't understand. How is that compared with stock compression which is 11:1?

 

[ivan1111]

ur mivec ECU SOLD ?

 

[HanZ85]

SIlver top 4 wire is for fuel saving yet performance rit?like tat i think there will be power limited nomatter how u mod it. juz mu 2cent~

 

[mysyncorp]

Sorry to bump in...

For MD and Normal Mivec if believe when highly rev the power is +-. Just from my experience using both engine. Cheers!!

 

[csl]

Normally remove all those so call power adding product and also the exhaust system to ori, the power will come back.