Aftermarket ITB seals and throttle spring bushes

[cortexx]

Hi Guys

Im rebuilding my rb26 ITB's and plan to yank out the seals from the butterly rods and replace them with a set of bushings machined from Fluorosint MT-01. It is a plastic that exhibits low friction co-efficient similar to teflon but is strong enough to be machined into precision pieces for the ITB usage . It also has amazing sealing ability in essence making a rigid bearing/spacer/seal that can withstand high boost applications with very minimal to no leakage.

Im also machineing a set of throttle spring bushings to hold the ITB springs , if you look at your setups closely after 15 minimum years or use - the original plastic parts are usually worn, shipped , broken etc and you cannot buy any of these parts from Nissan.

So if anyone is up for a set to replace the spring bushings and also the existing seals I will machine sets for you. The materials are relatively expensive and take alot of time to precision machine but the results would be awesome.

I will make mine first and document the results before i expect anyone else to pay anything..

If this interests you post here and eventually we'll have a solution to the leaky seal issue...

[MarusGTR]

How did you come across this material and what made you think about doing this enhancement? (Basically I'm asking where you got the inspiration)

[gtrjon]

im interested for more details and progression

[cortexx]

The inspiration for this came from :-

1) the fact that you cannot buy these seals from nissan , you have to instead buy a complete throttlebody assembly at horrible cost .

2) I'm always interested in improving something with newer technology and materials .

3) I have often seen people asking for a set of ITB's to replace their leaking ones (that i assume get ditched) right daryl ?

4) I actually came across this material while researching a plastic that can be precision machined and has low friction properties ( originally favouring teflon ptft bar ) but will also seal with no rubber and no added lubricant and stand up to the temps of the intake side of the skyline engine..

5) during building and restoring the subassemblies of my own engine I wished i could replace the spring bushings with new .

6) the thermal expansion rate of flurosint is almost identical to aluminum pretty much enabling the piece to be machined and fitted close enough to stop any kind of vacuum , boost leak from cold to operating temperature without binding and causing tighening of the throttle shaft.

How did you come across this material and what made you think about doing this enhancement? (Basically I'm asking where you got the inspiration)

[bobbo]

Very interesting. Do you have access to tooling that can produce a consistently accurate product?

[ColinR33]

I am interested!

[cortexx]

I have a decent lathe at my disposal , because of wear and tear on the ITB housings , im assuming each set would have to be individually made to the dimensions of the piece.

[caliber676]

I'd pick a set up if your still selling them.

[cortexx]

im still waiting for the materials to come , once i make the first set ill post details etc

[caliber676]

Sounds good, let me know when you do, definitely on my to do list with 9million other things

[dsmart]

I am also interested in a set if it works out. I still find it hard to accept that a suitable double lip seal hasnt been found

[cortexx]

Just an update guys - i now have 4 Ft length of flurosint 500 bar . It was really hard to come by - had to end up getting it from the states as no Canadian distributor had any .

Measuring my own ITB's i notice that the shafts all differ by as much a .0003 inch . This means for the best quality seal each bush will need to be made especially for each shaft , housing. The material is a hybrid polymer made from PTFE and Mica and as such self lubricates itself and is incredibly resilient.

I am going to rebuild one of mine after i do a submerged leak test to see how much the original seals leak at certain boost levels , then ill rebuild them with the new bushings and retest them and post the results here.

Also just thie week replaced my mini lathe with a 10 / 22 Industrial engine lathe so that i can tackle larger jobs and be more accurate .

[Fred-R]

I'm interested too

[caliber676]

So if we gave you measurements could you make them?

[cortexx]

Lets see how mine come out first , I'm using my own set as a guinepig first

Might be a good idea to send me your set and have me rebuild them for you , that way I can make them all precisely as possible and leak test them properly.