Port/Polishing ITB Inlet (pics)

[chrispy.clio]

Just been having a look at my ITB's and the inside surface is quite rough.

Has anyone polished theirs up just to get them a little smoother. I know that i dont wana port them any bigger as there will then be a step up into the cylinder head. Just wanted to know if anyone had done it. Surly it will improve flow

 

[Hutchie]

the surface of the inlet is puposed to be slightly rough (not polished, thats a myth) to prevent droplets of fuels settleing on the side.

although i feel that that is rough cast, a rub with something like 320 sill its "smoother" wont do any harm.

when i made my inlet manifold i made it all nice and smooth and then roughed it up slightly with 80 grit

 

[sideways danny]

portmatching to the head is worthwhile. they're cast fairly undersized (much like the standard manifold)

 

[Hutchie]

portmatching to the head is worthwhile. they're cast fairly undersized (much like the standard manifold)

match head and itb's to gasket????

 

[sideways danny]

no not really, the gasket is bigger than the port. you can use it as a guide, but dont go to the edge, and get it nice and acurate. The huge advantage with an ITB manifold is you can see all the way through, so you can match it very well to the head

 

[Hutchie]

no not really, the gasket is bigger than the port. you can use it as a guide, but dont go to the edge, and get it nice and acurate. The huge advantage with an ITB manifold is you can see all the way through, so you can match it very well to the head

indeed

 

[chrispy.clio]

portmatching to the head is worthwhile. they're cast fairly undersized (much like the standard manifold)

Would K-TEC be able to do this for a small charge

 

[sideways danny]

yeah, if they're doing the fitting, i'm sure Andy will do it for you

 

[chrispy.clio]

Arr thought you might say that, I can fit it myself.

Well i might have a blast at doing it myself.

Does look quite easy as the Mani is split into two bits.

 

[stan*]

gets some engineers blue and mark up the two faces.

then match and finnish on say a 50grit.

 

[jack_davey]

ive read that leaving the surface rough is good as it tends to make the airflow more turbulent which is good for fuel atomisation apparently, but I'm not sure how much truth there is in that theory.

 

[Hutchie]

ive read that leaving the surface rough is good as it tends to make the airflow more turbulent which is good for fuel atomisation apparently, but I'm not sure how much truth there is in that theory.

rough but not that rough