Turbo upgrade experiment..poor results

[swankmetal]

rob, take a look at my gallery. you will see before and after shots. the "slot", or "groove" is . 010 wide and should be centered between the tips of the long blades and the tips of the short blades. to do it that way, it has to be at an angle (sloping down towards center, if you're looking at the intake side). when we did mine, i hadn't seen one in real life, so it goes straight in and is RIGHT behind the tips of the long blade. still works fine though. and i think it's louder that way. the reason for it is that at low rpm, with a small exhaust housing, the turbo spools too quickly. it's trying to push too much air while spinning to slow. the engine won't accept all the air and tries to spit it back through the compressor wheel. air going both ways doesn't work to well. the slot allows the air to go AROUND the wheel and come back in the right way. eliminating surge.



that's how i understand it anyway.



dave

 

[JLEONARD]

Thanks Dave

 

[Forrest Nearing]

. 010" wide seems pretty small... obviously doesn't have to be huge, but factory is wider than that I believe... without one in front of me, I'm guessing ~. 050"?

 

[swankmetal]

thanks for catching that forrest. i meant . 100".



dave

 

[JLEONARD]

 meant . 100

Yea... you'd never cut a . 010" groove!!

 

[REakin]

Thanks for the info! Still not specific enough for me to feel comfortable cutting on the only turbo I've got. I guess I'll just keep pinching pinnies and buy one ready made! Thanks again!



Rob

 

[JLEONARD]

Anybody remember the Beatles Sgt Pepper album and the the song...

"It's getting better all the time"?

Yes it is.

I have a cardboard and duct tape model made of my new crossover pipe, some mods needed for the Freightliner 3 inch cast elbow, and I'm getting readuy to rock and roll.

Yep. . in addition... cranked in the fuel screw 1/2 turn more. . then had to lower the idle 200 rpm... yup, I'm gettin' there.