Port & Polish Explanation PLZ!!
08-Mar-2003, 04:02 PM
#1
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Location: Milton
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Port & Polish Explanation PLZ!!
Sup Everyone...Ive been having an on-going debate with a friend of mine who has a J-Body (Cavalier crap) on what Port and Polish really is and how it adds hp...can someone plz explain to me in detail so i can shut him up quickly...
THX
THX
08-Mar-2003, 04:04 PM
#2
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from what l was told that port and polished
is when they take the pistons out and bore the
hole making it bigger then , putting performance
pistons in, thus adding to the HP
l might be wrong though
is when they take the pistons out and bore the
hole making it bigger then , putting performance
pistons in, thus adding to the HP
l might be wrong though
08-Mar-2003, 06:15 PM
#4
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Originally posted by 1Sic4Dr
from what l was told that port and polished
is when they take the pistons out and bore the
hole making it bigger then , putting performance
pistons in, thus adding to the HP
l might be wrong though
from what l was told that port and polished
is when they take the pistons out and bore the
hole making it bigger then , putting performance
pistons in, thus adding to the HP
l might be wrong though
funny explanation: basically they take shoe polish and wax the cylinder head up really nice to make it shiny.
this bumps compression.. the shinier it is the more compression you get.. which adds hp. 
Serious explanation: port 'n polish involves the cylinder head not the block. an orignal cylinder head from factory is casted using sand investment powder, which leads to inconsistencies in the surface area. this hinders air flow. the ITR and CTR heads get the benefit if a mild P'nP after the casting is done, but all the other Civic/Teg motors don' t recieve this treament. basicially what a pnp does is removes these little inconsistencies, material is "polished" off which bumps compression and also the i/e ports are opened up and smoothened for better flow characterisitcs. pnp's are odne in different stages according to applicaton.. a motor designed for boost won't be treated with the same pnp job as one designed for all motor. Don't expect alot of agins from a pnp by itself.
09-Mar-2003, 04:55 AM
#7
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hehehe...a real pnp is when the head is put on a flow bench which is used basically to find the best way to shape the port's and where to take material off and where to leave material in the port's to find the best flow characteritics of the head....so a pro goes in with a gringer and starts removing material and polishes the port's to certain spec's...what ctr and itr's get is jsut cleaning the port's up not a real pnp job more like a polish...it's a science not jsut grinding material off and polish'ing to a mirror finish...I dont' knwo if this makes sense cause I'm tired as **** and it's really ******* late.........
09-Mar-2003, 05:01 AM
#8
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Like i said there's different stages of pnp's.. mild, wild, all-out race, etc. etc. For a professional job a flowbench would be a must, otherwise how would you know if you gained any flow at all? 
mine was done at leitner and all their PNP's are doen on a flowbench.. i'll have to go look for the results but a typica lrace prep on a GSR head would net +20-30 cfm across over stock..
if you're on a budget get some sandpaper and go nuts on the ports, although you might end up doign more harm then good.
mine was done at leitner and all their PNP's are doen on a flowbench.. i'll have to go look for the results but a typica lrace prep on a GSR head would net +20-30 cfm across over stock..if you're on a budget get some sandpaper and go nuts on the ports, although you might end up doign more harm then good.
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