Ive taken my intake manifolds off for the winter to do some work on them.

one thing i would like to do but i remember all the fuel atomization talk.
Anyone have real knowledge on this? or just guesses.
Anybody have any new info from articles or anything on the web on polishing a lower IM .what does the car community as a whole do?

Is this good to do ? what and where are the facts?

 

I smoothed out/polished my lower before my 00VI install. I won't ever know if it did anything though

 

There is NO fuel atomization in the IM, we are not carborated. Since the injector sprays into the CC the whole IM can be smooth as a babys bottom.

 

I polished mine after gasket matching it. But to match it to the intake ports on the head, that would be a LOT of material to remove. That's the way it is with the VE anyhow.

More photos can be seen here:
http://www.iwdwebdesign.com/maxima/intakeport.html

Before:


After:


Here's my upper IM:

 

What did you use to port the IM? That looks pretty good.

 

Standard Abrasives Port Kit SAI-260001 $39.88

The tapered sand paper cartridge rolls do wonders!! Forget stones just b/c the aluminum gets clogged in the pores too easily. But the sand paper rolls really make it easy. Then go to the fine sand paper cartridge roll to smooth it out a bit. Then use the buffer/polisher bit to really make a mirror finish!

I am about to port my exhaust manifolds in the next few days. I've already ported them, but since Nissan welded the tubular steel form the INSIDE, I am going to weld them from the outside and then port ALL the material out of the exhaust manifold.

Here are my exhaust porting pics that I did sometime last year:

Before:


After:


You see I couldn't port that much material b/c I didn't want to weaken the welds. Since it's steel, I had to use a carbide bit and let the metal shavings FLY. But this time, since I will weld them from the outside, it should be strong enough for the abuse I put on my motor daily.

More pics from my exhaust port work can be found here:
http://www.iwdwebdesign.com/maxima/studs.html

 

Ok thanks guys guess i can polish away i have scotch brite drums and they are amazing.


Aaron thanks for the exhaust idea i will do that to the stone racing headers i have. they are complete trash they are welded on the inside like that to. and the welds are huge .
i actually forgot about it until i saw your fine work
Looks like i have another project to do

 

I did the same to my 3.0 USIM and LIM... as far as power goes I didnt feel anything different (no comparing dyno results either). I did however feel a smoother reving motor. It would just jump into redline. Very similar to the result of adding my motorstorm UDP to it.

I have my 3.5 taken apart right now, I might as well do it on its LIM and see if it makes a difference. Then later on "alter my Upper Intake Manifold for better flow in the top end" and see how that goes