Thread: First Port&Polish attempt

Originally Posted by TLSheff

Regardless if you think you "fixed all vacuum leaks weeks before I did the LIM gasket and didn't change", you didn't. Mine pegs the gauge at 3/4+ throttle, if yours does not, there is a leak somewhere. You prolly just got it fixed once you put everything back together.

I did fix the vacuum leaks. I tested and tested again for leaks and everything was sound. Just because yours maxes out at 3/4 throttle doesn't mean mine does. My car has 200k.

Originally Posted by Z34Phoenix

OUCH... that blows man. the rotor pack wears to the case anyway. im not a fan of swapping cases as i feel this could result in a bad seal too. like said if you sanded the walls of the case it is time for a new blower.

Didn't sand them at all...just polish..

Air density has a lot to do with it. It's cooler and therefore more dense air as well.

I lost a solid 15-20 HP (and belt slip) between going non-coated rotors and coated. I think I put down 260 something non-coated and 280 coated.

If your belt was slipping on the dyno...that's more likely where the loss of power and inconsistencies came from more so than no coating on the rotors.

i have a guy thats polishing mine gonna be interesting to see how it came out

Originally Posted by buck531

I lost a solid 15-20 HP (and belt slip) between going non-coated rotors and coated. I think I put down 260 something non-coated and 280 coated.

damnnn 15-20? What caused the belt slipping?

Originally Posted by logan809

What caused the belt slipping?

Wrong sized belt.

the porting deff looks good we are all saying he screwed it up but only he knows about how much meterial he took out. If he used a polishing cotton fob with like white rouge compound I highly doubt he took of .001". If he used like sand paper then yeah he prolly took like .005" off. If he likes it then let it be. It was a really good first try and just take the advise about the insides no matter how rude they seem.


And any advise that bill gives rude or not is always true. Bill is a book of knowledge

Originally Posted by copgtp

He screwed the pooch on this one guy. All he had to do was either do some basic searching, or simply post a question about porting his case, and he would have come out with a nicely ported piece.

Instead he jumped into it like so many others do, and screwed it up.

I dont disagree with you copgtp. I searched and searched before I even took mine off then took 2 junk ones and practiced on, made a fixture for the mill and everything first.
Research is always the key. There isnt a mod I have done without 2 months of reading up on it. Hell I was on this forum 6 months before I finally decided to buy a gtp and get away from the turboed honda I had

Now I have a fixture I can bolt the blower case on and can port them quickly and keep all the angles right

Hey, copgtp, you're one to talk about jumping into things, you haven't the slightest clue what he used. I'm his older brothe, I do know, we used a soft cloth with white rouge compound on the inner walls. I have since ridden in the car and it made a significant difference in his car. And concerning him not knowing anything, our dad has over 25 years experience building motors, I think we know not to change displacement in a P&P. Ease up, he's new to the forum and gtps, and he is 16 years old at that!

Originally Posted by bluegtp91

Wrong sized belt.

This. I was running (I think at the time a 3.1) pulley and had a belt on for a 3.4. The graph looked like a wavy line.




Swapped to coated rotors and put down 280 hp. Probably just the belt slip though.

http://i283.photobucket.com/albums/k...31/ipsdyno.jpg if you want to enlarge it. Peak HP was 266.

Originally Posted by Pure2sin

Apples to oranges. Nobody is really going to know for sure because there was no before any after numbers. So the argument is moot.

I know your not even supposed to remove the gunk from inside the blower just because you want the seal between the rotors and the blower wall to be as close as it can get to compress the air. Although this is true I doubt he lost HP and even if he did I am sure over time with buildup he will gain in back. It's not like he took a Dremel to the inside of the case.

Am I assuming you know someone that did?

I used a sawzall on a case. Stood on the chair with a foot on the case and sawzalled!

Those cuts were with a sawzall. Then cleaned up with a dremel.


Here's where you want to smooth


Snout that I block plated via sawzall/jb well. Not as pretty.

I also smoothed the inlet just like your picture Bill.

Did you plug the coolant passages? Because I'm pretty sure it's paper thin there.