head porting and polishing

R

rwdrev

Member +
wondering if any1 knows a good company to port and polish the head on my gt, i have msgd kon at zisco, but wondering if any1 else knows of a good company??

:p
 
John@ECC

John@ECC

Lifer
We can also do it, give andy a call 028 92 666 555 on wednesday for a price etc or PM ECCSales. We can do heads on exchange to elimiate the downtime of the car being off the road.
 
wildchild

wildchild

Member +
can anyone pls let me know which part in the head needs porting and polishing and how much meat should be shaved off or diameter of inlet. should inlet manifold be ported too? to which length and what diameter? iam from, sri lanka and so i need to give exact figures since not many machinists know about them.
Thanks alot :)
will be repped :)
 
S

Skalabala

Member +
wildchild said:
can anyone pls let me know which part in the head needs porting and polishing and how much meat should be shaved off or diameter of inlet. should inlet manifold be ported too? to which length and what diameter? iam from, sri lanka and so i need to give exact figures since not many machinists know about them.
Thanks alot :)
will be repped :)
Click to expand...

Go to a reputable place and they will use a flow bench to make it flow optimal.
As for sizes. Intake manifold can be smoothed. And diameters, I will go for perfect gasket match.
You do not want to much material removed as it can make the ride uncomfortable, but good for a top end drag engine.
Concentrate on valve throat and valves and port roof and then gasket matching :)
 
sx_turbo

sx_turbo

Lifer
you do NOT want polishing,

and you dont want the intake smoothed, maybe remove the casting marks but not smooth it,

other than that completly agree with skalabala,

from experience, the exhaust throats can be enlarged by 2mm using the stock valves, and the inlets 1mm using the stock valves, if you dont enlarge the valve throats it will be completely pointless porting.

also try and find a good reputable engine builder who knows what there doing, not an engineering shop must be someone who local race boys know and stuff as there workmanship is the best and they dont charge obscene ammounts of money
 
A

AdamB

Member +
sx_turbo said:
you do NOT want polishing,

and you dont want the intake smoothed, maybe remove the casting marks but not smooth it,

other than that completly agree with skalabala,

from experience, the exhaust throats can be enlarged by 2mm using the stock valves, and the inlets 1mm using the stock valves, if you dont enlarge the valve throats it will be completely pointless porting.

also try and find a good reputable engine builder who knows what there doing, not an engineering shop must be someone who local race boys know and stuff as there workmanship is the best and they dont charge obscene ammounts of money
Click to expand...

x2 someone who has done head work before is your best bet, you could be wasting money and power down the drain otherwise.
 
S

Skalabala

Member +
Removing casting marks is smoothing it :)
And from my experience, smoothing and swirling a intake manifold makes good power.
In fact a huge amount of power lies with the piece before the head ;)
 
HYBRID

HYBRID

Super Moderator <a href="http://www.toyotagtturbo.
Weve been making heads for a very long time now and know exactly what to do to squeeze the most out of these little motors of ours :)

Also, weve supplied alot of tgtt members with heads, with a 100% success rate every time hehe ;)

Thanks
Kon
 
wildchild

wildchild

Member +
ok, so i smooth/polish the intake manifold. i can get the 4 ends increased in diameter but how abouth the length? surely nothing can be poked along the curved lines on the intake manifold.
then i have to increase diameter in the 4 head ports where the intake manifold fits?
what about the 4 ports on the otherside of the head where the exhaust manifold fits?
Am i getting this all wrong or should i port only the intake and exhaust ports on the valve area? would that make a difference since i will be using stock valves and i wont be expanding valve seat area so it will still be squeezing the same amounts of air and exhaust at the valve seats.
Any pics so that i can get an idea?

(Im running a Garret BB GT28r on a 5E)
 
T

Topher-EP82

Member +
this whole smoothing and polishing business...

scientifically physics tell us that the smoothest surface is not the best for airflow :S

as a physicist friend of mine once said, a car covered in sandpaper will have less drag than a very clean and shiny surface ;)

can this be applied to intake air flow...
 
S

Skalabala

Member +
Smooth = a dull scratched surface
Polish = chrome like finish
Open the valve throat with +2mm
Keep the stock manifold smooth and swirl it.
 
sx_turbo

sx_turbo

Lifer
wildchild said:
ok, so i smooth/polish the intake manifold. i can get the 4 ends increased in diameter but how abouth the length? surely nothing can be poked along the curved lines on the intake manifold.
then i have to increase diameter in the 4 head ports where the intake manifold fits?
what about the 4 ports on the otherside of the head where the exhaust manifold fits?
Am i getting this all wrong or should i port only the intake and exhaust ports on the valve area? would that make a difference since i will be using stock valves and i wont be expanding valve seat area so it will still be squeezing the same amounts of air and exhaust at the valve seats.
Any pics so that i can get an idea?

(Im running a Garret BB GT28r on a 5E)
Click to expand...

do not polish the intake manifold
 
B

bongskag

Member +
a beginner should first grind off the casting marks and blend them in nicely . this is step 1, you cant do any harm with that, and it gives you an idea on how to use the tool needed to do more work if you choose to. ;)
 
A

AdamB

Member +
Or do plenty of practice on a spare head, you'll have 8 ports, and 4 chambers to practice on, should be enough to get a fairly decent head. But you won't know how good it is until, A) its been on the car and the dyno, or B) a flow bench.
 
H

hkspower

Member +
we never have flow bench any of our heads and all ways had good gain... you need to know how much and were to remove...practice make's it perfect ;)
 
S

Skalabala

Member +
A great way to start is to use your fingers and P60-150 sand paper.
This will give you some good experience before you go and rip the head to shreds with an air pencil grinder and carbide bit.
 
wildchild

wildchild

Member +
like i have said before, i wont be doing this. its my machinists job (lathe works).
all i need to know is WHERE to port and HOW much.
 
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