Port & Polished Head

[CARENT]

bro, b4 u consider doin port n polish, i think its advisable to invest in some engine tuning devices such as cam pulleys n piggybacks to complement the increase in air flow....if not, there wun b huge effect.....just my opinion...cheerzzz

I have already done the rest that u have mentioned and am now thinking of upgrading my piggyback to Greddy E-Manage (now using S AFCII).

In the pipeline to upgrade Adj Fuel Reg and Bubble tank :)

 

[CARENT]

Well, the benefit in doing a proper PnP is as follows :-

1) Better airflow in both the intake and exhaust (because of porting and polishing). This is because usually, it is not smooth.

2) Smoother acceleration

3) Better pick up

4) Increase in HP by about 10bhp (be careful on the head skimming to ensure tht compression ratio is within limits)

After doing the PnP, u can feel ur acceleration and there will be less restriction (I thnk u know wht I mean - i.e. soemtimes u find tht u are not moving tht fast even when u are flat out on u gas pedal :frown: )

0 - 100 kmh will reduce!!

But I am always worried tht the mechanics are not tht good or are crooks. That is why i m asking around.

Don't want to be cheated !!!

Most times, mechanics will say 1 thing, then end up doing a whole lot of things then ur bill would bloat up like a Gigantic baloon... or, sometimes they will do something to ur engine so tht u would encounter problems a few days after, then go back to them to ask them what happen. They will then say something spoilt have to change... then charge u more... :thumpdown :thumpdown :thumpdown :thumpdown

 

[zamans98]

Image & Write-up Courtesy of Billzilla.Org

There is some debate weather or not it is worth polishing the inlet tract and inlet ports. Most engines these days have a light sand cast finish to them, and I believe that this is close to the optimum for creating a good 'boundary layer', which makes for a more effective inlet system. The best finish seems to be the one left by a '400 grit' sandpaper. The other school says that there is not time for the boundary layer to form and so a highly polished manifold & head is the go. I believe that most dyno tests show that a slightly roughened surface gives more power in most cases, so in that case I don't think that it is worth the cost and effort to polish the inlet manifold and head at all. Simply clean up the casting 'dags' that are always present.

Suprisingly, http://www.powerzone.com.my/index_eng.htm
also contain details on porting n polish. Check it out

 

[kennethfong]

very much well said, too smooth will increase fuel consumption but not horse power correspondingly.....

 

[Kopi]

fluid 101 theory in engineering...

 

[Rekalo]

Well, the benefit in doing a proper PnP is as follows :-

1) Better airflow in both the intake and exhaust (because of porting and polishing). This is because usually, it is not smooth.

2) Smoother acceleration

3) Better pick up

4) Increase in HP by about 10bhp (be careful on the head skimming to ensure tht compression ratio is within limits)

After doing the PnP, u can feel ur acceleration and there will be less restriction (I thnk u know wht I mean - i.e. soemtimes u find tht u are not moving tht fast even when u are flat out on u gas pedal :frown: )

0 - 100 kmh will reduce!!

But I am always worried tht the mechanics are not tht good or are crooks. That is why i m asking around.

Don't want to be cheated !!!

Most times, mechanics will say 1 thing, then end up doing a whole lot of things then ur bill would bloat up like a Gigantic baloon... or, sometimes they will do something to ur engine so tht u would encounter problems a few days after, then go back to them to ask them what happen. They will then say something spoilt have to change... then charge u more... :thumpdown :thumpdown :thumpdown :thumpdown

Hi, im just wondering, PNP will do changes on fuel consuption, if yes maybe in % how much the diffrent for DOCH 1.6 ?

 

[CARENT]

Well, i think tht the fuel consumption will increase a little bit but it all depends on how u drive and set the car.

Can set it to a more lean fuel setting.

Most of the time, after doing the PnP, u would tend to accelerate more!! So, up to the person driving whether high or low consumption..

 

[CARENT]

very much well said, too smooth will increase fuel consumption but not horse power correspondingly.....

The only way to test the car would be on Dyno.. before and after.

For a normal 4G93P DOHC, after PnP should give another 8 - 10bhp (on wheel)

But will have to Dyno la... Now my car giving me 118 bhp on wheel.

Will test out later

 

[crocky]

PnP also will increase heat in bay

 

[Rekalo]

The only way to test the car would be on Dyno.. before and after.

For a normal 4G93P DOHC, after PnP should give another 8 - 10bhp (on wheel)

But will have to Dyno la... Now my car giving me 118 bhp on wheel.

Will test out later

Wah...118 only if on wheel, if mine like that lagi teruk la

 

[CARENT]

PnP also will increase heat in bay

Well, It depends how your mechanic does the PnP...

Make sure tht when u use a metal gasket, don't skim too much off the head.

It will definitely heat up more. So have to run on richer fuel settings. Otherwise, ka boom......

This is because we will run the engine at higher compression (slightly)

 

[CARENT]

Wah...118 only if on wheel, if mine like that lagi teruk la

Bro, my one not yet PnP la...

So, after PnP, should be around 125 to 130bhp. Depending on the setting for the adj cam pulley and the fuel / ignition timing

Can use E-manage to handle the setting la....

 

[speedking]

Most of the time, after doing the PnP, u would tend to accelerate more!! So, up to the person driving whether high or low consumption..

i agree with this....coz throttle respond is better and ur engine rev lighter

 

[Rekalo]

Bro, my one not yet PnP la...

So, after PnP, should be around 125 to 130bhp. Depending on the setting for the adj cam pulley and the fuel / ignition timing

Can use E-manage to handle the setting la....

OIC...

 

[CARENT]

Anyone interested in doing PnP?

Maybe can get collective nego....

 

[et5828]

nice to meet u carent
i'm insterested in pnp too...
hopefully the pnp will increase my hp with my high cam
if u goin to any good shop
mind tell me also ya

 

[kennethfong]

hi, don't they have any ported n polished ready intake manifold for sale??? another question though, any other intake manifold from higher end series of engine compatible with our 4g9x??? that's another way 2 work around......

if i have the dough, would have gone for 4 throttle with independent controller eg motec haltec bla bla......

 

[whatdamn]

carent,
i'd recommend powerzone for their PnP, have you asked for a sectioned view of the before and after PnP-ed head? if you haven't, i suggest u head on there and ask Mr. Zul to show it to you...you should be impressed at the ammount of detail put into porting and polishing the damn head! i was surprised myself when i saw it. pricey but you get what you pay for. plus, mr. zul is a certified engineer. :)

 

[CARENT]

carent,
i'd recommend powerzone for their PnP, have you asked for a sectioned view of the before and after PnP-ed head? if you haven't, i suggest u head on there and ask Mr. Zul to show it to you...you should be impressed at the ammount of detail put into porting and polishing the damn head! i was surprised myself when i saw it. pricey but you get what you pay for. plus, mr. zul is a certified engineer. :)

Thanks bro... Will look into it and see how is it like.
Well, I think u r right... u do pay extra for extra work done. Tht is why, I am doing a survey of what they do that makes a difference in a PnP.

Some people will tend to leave out the harder stuff because it is time consuming.

I have heard that the valve profiling and valve seat cutting is very difficult. and the chamber balancing. :bath:

Has anyone done it at Powerzone and would like to sharetheir exp???

 

[CARENT]

nice to meet u carent
i'm insterested in pnp too...
hopefully the pnp will increase my hp with my high cam
if u goin to any good shop
mind tell me also ya

wht is ur contact number??

mine is 017-888 9518

Will sms u..