First build in years

[dieselguy86]

Hi all,

This is my first build thread here. I built my first gt around 15 years ago. Have always wanted to build a proper one since. The last few years ive started a turbo shop and and have finally collected the right bits. I'll be going with a Borg Warner k27 based engine. Turbine is 76mmx64mm 12 blade unit, compressor is 58mmx82mm titanium 7+7 wheel. The shaft is 10mm so hoping i can use some 61900 bearings i have. The shaft is measuring 9.95mm which is an easy sliding fit, but i feel is too loose. I ordered a new shaft hoping it's .01-.02 bigger.

Thinking of maybe doing a sealed shaft tunnel, using a tiny bit of bleed air to cool the rear bearing and to also help force the oil out along with a scavenge pump. But i may very well go with the loss lubrication method that the RC engines use, is just too simple to ignore.

Im also playing with the idea of converting the radial wheel to a mixed flow one to help with packaging things.

For the fuel system it'll be the normal kero, but i want to use "direct injection" instead of the evap system. Plan is to have the fuel manifold on the back of the diffuser, with johns "racket-jectors" sticking into the cc's front wall to spray.

Lots to figure out yet, but i feel i now atleast have a plan, along with most of the bits. Im not cad savvy, so it'll most likely be a "napkin blueprint" kind of engine.

Thoughts, as always, welcomed and encouraged! -joe

[dieselguy86]

Wheel came in today, here's my first impression:

1) titanium is gorgeous
2) titanium makes for a heavy wheel

I was not expecting the blades to be so thick, pretty sure this wheel could suck in small trees and keep on going. Although the machined titanium is absolutely beautiful, next time im going to use a billet aluminum one from KTS.

[enginewhisperer]

yeah that definitely looks overkill for titanium!

I guess they just used the same design as the aluminium version.

[dieselguy86]

My guess is it was designed for a corrosive or harsh environment. A saltwater boat or somewhere with alot of sand. You'd think air filters would catch the sand, but ive rebuilt alot of turbos from dry/sandy areas that the compressors were absolutley beat from sand particles. Worn blade leading edges and tips, and severe pitting on the pressure side of the blades.

-Joe