GTP coated rotors, case clearance+coating probs.(Soda blasting :).. )

suutari

Registered User
Hi!
okay, I managed to size my old style gen 1 blower (OD25% TB 20psi 315 whp) and bought a good set off -98 gtp rotors..

Sanded the rear of the case flat so I managed to save the ported case and snout from the old unit.

(Same blower that I did the rotor pack bearing rebuild years ago and it was my own stupidy that it went now..temps got too high this time, 15+kmiles and really abusing it meantime, drag race+street etc. not bad)

Then the questions:

I have some rubbing occurring when I assemble the unit. The front end off the rotors rubs the case the whole circle.
What could cause this?
It´s really heavy to turn and I think I have to remove the coating from the edges on this part anyhow!!!

Anyone else had some clearance issues with GTP coated rotors???

I´m still using this set cause the gtp:s have lower mileage rotor bearings ( Not rebuilding a pack anymore :) )

Other question:
Should I peel/use some acid to take off the coating allready since With my setup I think I will get into trouble with the intercooler( As I read today..wish that I´ve knowed that before)

I could use some thin piston coating instead to keep the temps low and coat rear of the case too at the same time to prevent sticky effect? This would only be made to keep the rotor from sizing so badly/keep rotors cooler..not for tight clearance..

(This new blower will anyhow have at least 0.015" back clearance..just in case.)

When the edges wear off because the high temps+boost I think the rest off the coating flyes to my IC!!

What do you think and what would dissolve the cotaing ones and for all so I could get easily bare aluminium rotors?

thank you advance

Sami
Finland

PS: not needing the extra 1-3psi since I´m doing sc+turbo setup now..turbo will take over after 3500-4000rpm.
 
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Wayyy ahead of you guys ;)

Had the rotorpack today "Sodablasted" with baking soda. Same method that they use to clean the statue of liberty in N.Y.

VERY NICE RESULTS!!! So no worryes..if you don´t want that teflon in your cooler but want to use new rotor packs with good bearings this is the answer.

Car has been allready put together and I´m taking it for a test drive tomorrow :)

Tags, cleaning the rotors, coating removal etc.

All the clearances are now spot on!
 

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Yes, and the best part is the after cleaning using only normal water that dissolves any soda residue!!! ?

You don´t need to dismantle or protect the rotorbearings/seals etc. if you don´t want. Very nice results and 0 harm to basic surfaces.

If there is littel amount of soda left that is no biggie eather. 0 harmfull "normal" baking soda that is soft (They have different crystal sizes depending on the job). You can eat it :D!

Yes, I was a little bit suprised of this method too..really nice stuff. First time I saw this soda blasting in my life.

PS: Now that I know this..!"#%"# I should have taken the whole unit for a nice clean up :)..damn..
 
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I got a question, if someone was to get their IC all tefloned up, what would be the best method of cleaning it out? Take it out and hook up a high pressured air compressor to it and blow it out? Good chance that might not even do it eh?
 
Just curious, you had the teflon removed from the newer coated pack?

I know when I did my blower porting, I ate through the case on the inlet side and had it welded up. Thought the welding warped my case, because when all assembled, it was hard to turn. Took it all back apart, had the case dyed by my machinist so I could see where it was binding, and it didn't bind when re-assembled. Go figure. Can't say what caused it, but sometimes taking things back apart does the trick.
 
I would say that the best way to clean the IC would be to reverse the SC flow thru the IC leaving the blocked end without anything.

then revving the engine thru bypass etc...

I really don´t know where you could find so big airpumps more easily..grazy I know but should work!


Yep, i used dye too and everything worked nicely. blower has now been used quite a bit and no probs.
 
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