DOHC to SOHC

[!!4g91!!]

dis u gotta go to a workshop wit dis device.it checks ur compression,duh.hehe .mayb ur pistons rings r worn off.or a crack in ur pistons.or u might need 2 rebore ur block...change new pistons...

Wah.. ur engine quite good lor.. i got at 50km.. sigh
its done by yesterday with result at 9:1 and someting he said about ??bar (blur)..

you say like your engine gonna fall apart.. maybe the problem is not with the engine head.. with the engine block..

the pomen said its come from my block or head but he not so sure..
Need to check again by end of the week bcoz need extra time checking for sure..

check ur GB...gear ratio sometime cause this kind of problem...
thus check ur ECU....
metal gasket on N/A car?? wht a waste..
Good Luck..

already try to tuning by computer but their said my ignition timing problem and under power..
gear ratio?? no idea
metal gasket is recommended from zth forummer.. i just try it out bcoz of this problem.. Do u have any idea is its not good for n/a car?

 

[mag9556]

nope, didnt mention like that... just a waste only if for me... normally only turbo cars use metal gasket onli...
mine still using the normal gasket but mitsubishi ori wan la...somemore metel gasket expensive woh...

 

[huakenny]

yea..installing metal gasket normally for those turbo engine who wanna up boost...needs metal gasket to witstand the boost level as well as the compression level.

instal metal gasket in standard na engine doesnt seem to gv any improvement effect....kinda waste lo...

btw, i guess ur engine its time to overhaul...

 

[!!4g91!!]

nope, didnt mention like that... just a waste only if for me... normally only turbo cars use metal gasket onli...
mine still using the normal gasket but mitsubishi ori wan la...somemore metel gasket expensive woh...

yup.. for metal gasket alone cost me 120bucks then installation about 100bucks.. wat a waste lor.. sigh..
thanks dude..

yea..installing metal gasket normally for those turbo engine who wanna up boost...needs metal gasket to witstand the boost level as well as the compression level.

instal metal gasket in standard na engine doesnt seem to gv any improvement effect....kinda waste lo...

btw, i guess ur engine its time to overhaul...

oic.. I guest so need overhaul but need confirm where got wrong later not waste money to much... on my mind still worry which one need to do.. issit mechanical or electronic problem.. my plan is to check within 2 workshop the see issit same answer from them.. later i update here to ask all of ur opinion.. thnks dude..

 

[huakenny]

oledi diagnose?

 

[ACQ2305]

but hw cme 50++km ody need 2 overhaul? mines ody 53++km still like new...must b sumthng else la bro..unless it was really trash b4 kena potong...any smoke frm exhaust wen accelerating? white,blueish? if yes might piston crack,piston ring,or need 2 top overhaul.. bt if u say ur ignition lari,mayb tats d prob... hehe... frm wat i knw abt cars only la...

 

[!!4g91!!]

oledi diagnose?

Bro.. diagnose.. what is it for? Im blur on this... myb u can explaint me shortly.. need help..

but hw cme 50++km ody need 2 overhaul? mines ody 53++km still like new...must b sumthng else la bro..unless it was really trash b4 kena potong...any smoke frm exhaust wen accelerating? white,blueish? if yes might piston crack,piston ring,or need 2 top overhaul.. bt if u say ur ignition lari,mayb tats d prob... hehe... frm wat i knw abt cars only la...

nope.. b4 i owned this car its belong to my brother.. he got this engine at 50++km and then now was 130km++.. my brother gave to me coz he give up with the engine then i owned this underpower car.. hehe:cry_smile:
i got anther new car oso proton car with ori engine then i can feel the difference between SOHC and DOHC engine.. Here i got good opinion and suggestion from all sifus and will be practic to solve this engine problem then no need SOHC management..
Bro.. ur engine from auto version ar??.. mine was manual but underpower la..

 

[Dino@Casper]

Are actually going to say that a SOHC 4G15 is gonna be more powerfull then ur car???... u are going to get fired very soon man.. u need to get ur facts correct

 

[!!4g91!!]

yaya.. emmm.. thats something wrong in my car hood.. need to find the prob.. i know i was be wrong if say SOHC more ump than DOHC.. hehe..

anyone dont fired me ok.. haha

 

[calvin9683]

dude....
dun say till 4G91 so useless ler....

one thing abt ignition timing....
if din tune properly ur car really no power la.....
get the tuning right....

for twin cam....
the power come at higher rpm la....
city drive will b kindda sluggish....
if aircond on the worst.....
but if u off aircond n play high rev...
u'll love it.....

btw....
saw u r also from JB.....
care to join JB zth member's for TT???
we oso can share share experience on 4G91....
heehee

 

[kennethfong]

fren

if ur talking bout the thicker than usual metal head gasket, that'll reduce ur compression ratio rather than increasing it which is EXTREMELY bad for NA engines....

the reason ppl put thicker gasket is to reduce the compression ratio so that a higher boost level can be obtained SAFELY without blowing the engine, but do you have a turbine or supercharger? think again why do u need a thicker gasket if ur never gonna get a positive boost?

for NA engine, u need to increase ur compression ratio and not reducing it, if that's case than u r downgrading ur engine and not upgrading it, hope u understand the basics of what u gonna mod before modding and regret....

anyway this advice is only applicable if u install THICKER metal gasket than ur original ones..... sorry if this advice is a bit harsh, but good medicine is always bitter....

other ways to increase compression ratio is to skim ur head, getting a high compression pistons.... that will definitely get u MORE POWER....

 

[kennethfong]

so fren, what i suggest u g o change back ur ori thin gasket first, talk bout engine management later, after that, u'll be getting a lil bit more power, then think bout do you need an engine management, of coz definitely engine management is good but make sure u get one which can control both fuel and ignition so u can play with high advance at the right fueling at each and every RPM range..... and if u insist on engine management, go get at least an emanage ultimate or unichip piggyback which can control ur fuel n ignition, or even better a standalone which can cater for any unlimited future mods in the future like super oversized billet throttle body or whatever bla bla bla endless mod to be catered for.....

 

[kennethfong]

i saw u mentioned compression ratio 9:1, that is like an EVO 3 turbo compression ratio, in the world of NA and normally an NA engine performs at least 9.5:1 compression ratio, however loads of stock NA cars are running more than that maybe like 10:1, mivec n vtecs are very high too, the world's highest compression ratio vehicle is the honda s2000 at 12.5 CR at 250 HP which i'm not sure whether the record has been replaced by new makes...

 

[!!4g91!!]

dude....
dun say till 4G91 so useless ler....

one thing abt ignition timing....
if din tune properly ur car really no power la.....
get the tuning right....

for twin cam....
the power come at higher rpm la....
city drive will b kindda sluggish....
if aircond on the worst.....
but if u off aircond n play high rev...
u'll love it.....

btw....
saw u r also from JB.....
care to join JB zth member's for TT???
we oso can share share experience on 4G91....
heehee

oic but i oso cant feel any power on high revision.. tarik till 6000 rpm then lepas clutch its immediate drop and oni little spin on wheel on 1st gear then uhh..
already check within 2 days ago and the pomen said my ECU got problem and need to replace another.. cost me 450 bucks.. then another low compression to solve but still in process for checking..

fren

if ur talking bout the thicker than usual metal head gasket, that'll reduce ur compression ratio rather than increasing it which is EXTREMELY bad for NA engines....

the reason ppl put thicker gasket is to reduce the compression ratio so that a higher boost level can be obtained SAFELY without blowing the engine, but do you have a turbine or supercharger? think again why do u need a thicker gasket if ur never gonna get a positive boost?

for NA engine, u need to increase ur compression ratio and not reducing it, if that's case than u r downgrading ur engine and not upgrading it, hope u understand the basics of what u gonna mod before modding and regret....

anyway this advice is only applicable if u install THICKER metal gasket than ur original ones..... sorry if this advice is a bit harsh, but good medicine is always bitter....

other ways to increase compression ratio is to skim ur head, getting a high compression pistons.... that will definitely get u MORE POWER....

na engine.. alamak i just got a wrong info tech by someone that he said metal gasket is for increase the compression then buy this product from him.. before and after install still same never improvement.. Got confirmation from pomen that my ECU has been short circuit and replace by today.. didn't get information yet.. Hope this 1 problem will settle and another prob need to solve..
"low compression" oh my.. waste a money quite a lot.. take out the head and see what they can do.. no info yet.. myb evening will know it.. sigh:angry_smile:

so fren, what i suggest u g o change back ur ori thin gasket first, talk bout engine management later, after that, u'll be getting a lil bit more power, then think bout do you need an engine management, of coz definitely engine management is good but make sure u get one which can control both fuel and ignition so u can play with high advance at the right fueling at each and every RPM range..... and if u insist on engine management, go get at least an emanage ultimate or unichip piggyback which can control ur fuel n ignition, or even better a standalone which can cater for any unlimited future mods in the future like super oversized billet throttle body or whatever bla bla bla endless mod to be catered for.....

ya.. guest what? you are rite bro.. The pomen oso say like that.. alamak.. my original gasket has been throw away.. damn..
bro.. how much its cost for standalone ECU or unichip piggyback??
what da difference between standalone ECU or unichip piggyback?? noob here..

i saw u mentioned compression ratio 9:1, that is like an EVO 3 turbo compression ratio, in the world of NA and normally an NA engine performs at least 9.5:1 compression ratio, however loads of stock NA cars are running more than that maybe like 10:1, mivec n vtecs are very high too, the world's highest compression ratio vehicle is the honda s2000 at 12.5 CR at 250 HP which i'm not sure whether the record has been replaced by new makes...

ya pomen said 9:1 and their suspect my piston kong oledi or my block scratch..
i dont have any idea on that.. let see what they get by today..
bro.. do u know what is the compression spec for 4g91?

 

[calvin9683]

hmm.....
guess u better learn more la.....
if not ur mechanic tell u wat then u do wat....
like doing blindly oso.....

abt the metal gasket....
mayb urs is the thin one ler???
ask the seller properly...
before u go shooting at him....
wahahaha.....

pull till 6k n dump clutch oni a bit wheel spin????
how long hav u been using ur clutch???
but when u say the rpm drop....
doesnt sound like clutch slip ler....

since u edi say ur engine use for so long...
y not one shot open up everythin n do overhaul???
at the same time if piston got prob...
change 1.6 piston lo....higher compression n bigger.....
then mayb at the same time can do pnp ma....
hahahaha......

dun bother find ur old gasket la.....
cannot b reused wei....
if u wanna reuse oso can la....
but then u bear the risk urself lo....
heehee.....

anyway....
u interested to join JB zth members for TT???
come la....
all damn friendly one......

 

[kennethfong]

unichip or emanage will cost u below RM 2k, standalone is a bit more expensive at the region of 2k plus.... piggyback is a device to cheat n fool ur ori ECU feeding modified data to ur ECU to process, so u still need ur ori ECU to run ur car.... for standalone u need to replace the whole ECU, then ur ori ECU can throw to the sea (ok lar dun throw keep it)....

also as wat calvin said, ask ur seller whether the gasket u bought is high or low compression, and wat's the thickness.... getting a replacement original gasket usually dont cost much, just few hundreds with labour, n u should be getting wat u should have gotten the actual power in the first place.....ya of coz the old gasket is thrown away, it's just a cheap thing and can't be reused....

go do a search there are many other factors contributing to compression loss, such as worn piston ring bla bla bla, n u'll notice ur exhaust is puffing different colour smokes which is burning ur engine oil, which u need to always top ur engine oil for this instance....

 

[calvin9683]

kfong's replay is always so precise la......
y not u solve ur engine mechanical probs 1st???
then oni think of piggyback???

n yeah.....
the gasket dont cost much...
its the labour dat gonna cost u.....

its good to monitor ur engine oil oso la.....
if got lesser then u'll know the prob la...
so far...
my engine wont makan engine oil.....
even how hard u tekan....
n one thingy good abt 4g91...
FC damn nice...
last time no matter how i tarik or drive slow...
FC oso same oni....RM75 confirm gimme 450km....
now diff story edi la...
wahahahaha

come on la...
i've been askin u to come TT.....
come out then we can talk more bout it ma....
i oso can intro mechanic to u......

 

[!!4g91!!]

hmm.....
guess u better learn more la.....
if not ur mechanic tell u wat then u do wat....
like doing blindly oso.....

abt the metal gasket....
mayb urs is the thin one ler???
ask the seller properly...
before u go shooting at him....
wahahaha.....

unichip or emanage will cost u below RM 2k, standalone is a bit more expensive at the region of 2k plus.... piggyback is a device to cheat n fool ur ori ECU feeding modified data to ur ECU to process, so u still need ur ori ECU to run ur car.... for standalone u need to replace the whole ECU, then ur ori ECU can throw to the sea (ok lar dun throw keep it)....

kfong's replay is always so precise la......
y not u solve ur engine mechanical probs 1st???
then oni think of piggyback???

come on la...
i've been askin u to come TT.....
come out then we can talk more bout it ma....
i oso can intro mechanic to u......

calvin9683 n kennethfong;
Thanks for ur opinion..
i bought the metal gasket is thin one.. 0.5mm.. the mech said no need to replace the original coz this gasket is for performance.. no idea just follow their order.. save my bucks.. hehe

pergh.. after change the ecu the problem still not solve but no cost charges to me and save my bucks again hehe.. still underpower.. the mech said not ecu problem myb block or head got wrong tuning..
then after open the head uhh.. guest wat?.. block got a lot of scratch.. ring worn out n piston totally rubbish.. aiseym.. must do top overhauld.. have to change piston.. luckily i got budjet on that but which piston will be better is still on my mind?? anyone can help me? i just prefer little bit upgrade..
case: if i change to oversize piston how about temperature? increase rite?
1. then how about the risk and solution to protect the block or head?
2. have to change my ecu? my injector already 240cc
3. how about the head or conrod need to change oso ar?
4. etc

 

[kennethfong]

1. oversized piston involves reboring ur block, u intend to do a rebore? can ask around wat's the better piston to use for ur engine, i'm not much into reboring coz if the rebore is not done PERFECTLY, ur block is screwed, n u've to change a new block which needs new approval from JPJ Kawal Selia Puspakom all over again....and after a new rebore ur increasing ur cubic capacity, depends on the work done, maybe can use back ur current cooling system to sustain the heat disposed....
2. interpreting from ur intention, ur not modding anything for now, using back ur ori ECU and injector is more than sufficient, is ur ori injector 240cc? if yes use back....
3. no need to change, ori conrod is sufficient to withstand the power output....

from wat u said, looks like u definitely need a top overhaul...but wat u mean by piston totally rubbish? if ur talking bout the colour changes that's nothing big to worry bout....

 

[calvin9683]

bro...
i'd suggest u to go for 1.6 pistons....
even single cam ones edi good enuf.....
its edi high compression......

if u r worried abt reboring ur engine block.....
u can change it....
if u r thinkin dat its troublesome to do another inspection....
can ketuk back ur ori engine number....
wahahaha.....

u edi got the 240cc injectors......
just add in a bigger throttle body....
then slowly put in piggyback.....
viola...

ur ori radiator woundnt b sufficient....
even if u take out the thermostat.....
but then need to test oni know la..
under normal driving conditions shouldnt hav probs.....
unless u go rev during hot weather la....
then u can see the temperature gauge goin up.....

ur engine head is compatible....
so dun worry la......
mayb can do pnp at the same time???
good luck to ur project la....

where r u doin ur engine huh????
some famous mech???
giv some info la.....
heehee

hmm....
still no reply abt coming TT????
not interested huh???