port n polish cylinder head gain

[sideksepakragabulat]

hi guys..

tried using the "search" button and doesn't exactly found topic that could answer my questions..so i just start a new one..hopefully can get answer to my questions..

i had en EF-JL L2s 660t engine in my kancil with mid stage upgrade include a TD04HL-15G+72mm pistons+fuel reg+supra fuel pump+390cc injectors all manage by emanage blue small edition..now the car shown signs that it needs a major overhaul..and to add to the headache the clutch also need to be change/repad..and also a crack cylinder head..

with those parts above i've done nothing to the cylinder head except for removing a chunk in it chamber becos i found marking on piston that look like the piston had hit on them..and that will be pretty much the head work i've perform..

for this major overhaul i was thinking about to do a proper up to bottom reinforcement..i figure out all the part i needs and then this come through my mind..my new cylinder head have a stock chamber size matching oem block size..since i used an oversize piston do i need to rebore also the cylinder head chamber matching the new piston bore size?and also i found out that the chamber surface is a bit rough..it look like meleleh..differ from other cylinder head that i found on the web..it was so smooth and almost mirror finish look..does the chamber needs to look like that?

with almost of the part will be oem size(intake,valve spring,cam,valve)will there any gain if this port n polish being done?is it worth the money?and also i was thinking to use slightly bigger TB since the turbo i used now is quit big for my application..i just want to polish the exhaust port to mirror finish look since i heard it can help with my spool time..or are there any suggestion on how i could increase my cylinder head CFM to harvest full potential on my engine and turbo?

a bit lost here and would appreciate any suggestion..tq

 

[ken yeang]

when you say "izit worth the money?", how much is that exactly?

Becoz I have seen someone done their pnp using sandpaper oni...(workshop charged him rm80 pulak. )

 

[sideksepakragabulat]

ask powerzone and they quote me for rm1.2k..that include porting,polishing,profiling chamber,flow test..average workshop asking about rm600 manual port n polish..not even try to ask nastyportflow..i think around 1k and above..using sand paper only i think i can diy it myself but i fear it will not be the exact same amount for every chamber..rather than making power i afraid it will do the opposite..better let someone with better experience do it for me..

 

[Izso]

Powerzone and Nastyportflow are quite well known for PNP jobs. But if you ask whether they do a good job or not I wouldn't know since no one has ever praised nor condemned their work.

And like you said - a badly done PNP will reduce power (I would know, I experienced it). Personally I would go find your trusted mech or a friends trusted mech and have the mech do the work. Going with an unknown tuner might not do you any good.

 

[Supra_Fanatics]

Do engine balancing as well

 

[ken yeang]

since the engine is opened up, might as well beef-up the internals.....
Upgrade oil pump, water pump too....

 

[sideksepakragabulat]

a bit lost on engine balanced..do we need it when doing a major overhaul?i'm planning to change my piston with same size piston but from different car..also planning changing bottom ends bearings as well..is it a must after changing this parts?

totally agree on finding the right guy for the job..but how much gain will i see with all the head internals still stock?anything over rm400 for me is a big $$$ spent on upgrade/modi on a single part..if it is a must and provide good gain i will consider it..trying to put all this works around 3-4k max..

yup..kancil engine is a bit pain in the ass when it come to change all those tear n wear parts..since the engine will be on the floor,all the beltings,water pump etc will need to be change..

 

[Izso]

You don't need to do balancing la. That's overkill. But if got budget why not?

And if your budget is tight then no need PNP also, just replace all worn parts, skim head a bit, replace larger pistons and replace bearings, settle!

 

[gunnerzz]

when you say "izit worth the money?", how much is that exactly?

Becoz I have seen someone done their pnp using sandpaper oni...(workshop charged him rm80 pulak. )

RM80 for 'sand' and polish...hahaha

 

[ken yeang]

hahahaha, i can do it even cheaper....

Buy sandpaper.....local quality paper (80sen/piece) from hardware store

jolok-jolok the sand paper at the intake, plenum......
Blow-blow away the loose sand...
Install back the components...

prepare to feel the power of Pnp....

 

[sideksepakragabulat]

You don't need to do balancing la. That's overkill. But if got budget why not?

And if your budget is tight then no need PNP also, just replace all worn parts, skim head a bit, replace larger pistons and replace bearings, settle!

can bro explain a bit what is balancing?will try google around in also bout this balancing..

already using bigger pistons..couple it with stock heads it seem not much different in power la..just been thinking recently..i had a bigger pistons and bigger tebo..how can i improve the engine efficiency while the cylinder head flow stock CFM..have done as your advise back then but still don't improve as much as i target it..since the engine need to be rebuild again i was thinking about increasing overall flow as well..what the points of having everything oversize but flow equal to stock right?

 

[Izso]

can bro explain a bit what is balancing?will try google around in also bout this balancing..

already using bigger pistons..couple it with stock heads it seem not much different in power la..just been thinking recently..i had a bigger pistons and bigger tebo..how can i improve the engine efficiency while the cylinder head flow stock CFM..have done as your advise back then but still don't improve as much as i target it..since the engine need to be rebuild again i was thinking about increasing overall flow as well..what the points of having everything oversize but flow equal to stock right?

Balancing is when you take every single part of your engine and you lighten it and balance it. Like taking the crank shaft, crank pulley, clutch and balance it so it turns with minimal vibration so it turns faster and better.

You're the first one I've ever seen that has done oversized pistons and said no gain. But then again, you didn't say if you retuned your car with the mods?

 

[sideksepakragabulat]

actually i've seen a good gain but i doubt it came from my oversize pistons..the only thing i can see improved is engine respond..i used td04-09 tebo with stock and oversize piston..with slightly bigger injector and safc,my engine produce around 35-40hp more than stock..spool time seem like the same or maybe 1-200 rpm earlier with oversize pistons..the only significant gain i see is on how easy my rpm climbs compare to stock setup and i think that was all it..i have 2 dyno sheet i copied from kcarlife forum that show 2 different engine(but still in the same family)with different engine mod..1st engine used all stock part using only td04L-13G..he only install banana and twist a lil bit on ignition timing got around 14+hp with 1.9 bar off boost..the other one used various upgraded part like oversize piston,bigger injector,high cam,emanage+3 bar map sensor,same tebo but hybrid with smaller turbine housing produce almost the same hp at the same boost level..the only different on their dyno sheet is on how the power curve appear..one with only tebo upgrade achieve those hp very late on rpm but power on higher rpm seems endless..the one with everything in his engine achieve it a bit sooner but with the cost off drop power in higher rpm...

in my case it's a bit different though..i upgrade my tebo to bigger than previous hoping for hp increase but got the opposite result..IMHO oversize pistons only would not benefits as much if everything else doesn't match to each other..but since i've made a mistake by using oversize piston before i upgrade others part,i have to take a step backward and revise again what exactly my engine needs the most to gain full benefit of using bigger pistons..

read some article on importance off engine balancing...seems like worth the money doing it if i can afford it..the best quote i've read about this engine balancing is "power cost money...RELIABLE power cost even more money"...

 

[Izso]

that last part of your reply is very true! hahaha!

Ok to be honest I have no idea how it works for your car but on my NA car the piston upgrade was the best thing I did for my car. Power throughout the rev range increased, less effort for same power, and the funniest thing was better FC. It's like they say - no replacement for displacement!

 

[sideksepakragabulat]

that the magic part when playing with EF-JL (mira) engine..on NA engine upgrade to bigger piston can almost see instant performance increase becos the engine comp ratio has increase also..in my case,i need to run bigger piston while maintaining stock comp ratio in oder tu run higher boost on a bigger tebo..running higher boost on smaller tebo seem not to be best idea since it run out of breath easily..

i'm not a mech and far from being a race engineer whatsoever..done some reading and asking around and i found that the general idea changing a bigger piston on a turbocharged engine is to increase more volume over stock..that make me thinking on my car setup..how on earth i can increase the engine volume with just change the piston only while others like head,intake manifold,TB still stock..that why i need to know if it worth doing the head jobs or there's other way that could increase the air volume..

 

[l2s_turbo]

that the magic part when playing with EF-JL (mira) engine..on NA engine upgrade to bigger piston can almost see instant performance increase becos the engine comp ratio has increase also..in my case,i need to run bigger piston while maintaining stock comp ratio in oder tu run higher boost on a bigger tebo..running higher boost on smaller tebo seem not to be best idea since it run out of breath easily..

i'm not a mech and far from being a race engineer whatsoever..done some reading and asking around and i found that the general idea changing a bigger piston on a turbocharged engine is to increase more volume over stock..that make me thinking on my car setup..how on earth i can increase the engine volume with just change the piston only while others like head,intake manifold,TB still stock..that why i need to know if it worth doing the head jobs or there's other way that could increase the air volume..

Bro, take a look back at your down pipe size.. if your intake volume has changed, but your exhaust volume did not change, it'll give you downside performance.. just like ppl say.. "makan banyak tapi berak sikit" you know what i mean? Engine are not like our stomach can dissolve some of the foods passes thru... hehe...