looking for the smallest physical size turbo that would support up to 500 hp due to packaging constraints, going to use it on a 2 cycle outboard,probably will run it at 450 hp though, and figuring ball bearing would be best for fastest spool up, and i'm assuming its oiling requirements would be less as i'd like to oil it w/ the crank driven oil injection pump. thanks!!

 

Google "Worlds smallest turbocharger". I can't remember the website, but they have a tiny (near fist sized) turbo.

 

The worlds smallest turbo isn't going to support 500hp. Wtf.

 

How many hp is the engine now? How many cc? A member here, mnlx has turbo'd some high hp 2 stroke drag sleds. He'll likely chime in with ACTUAL info

 

i would look for a 2 cycle turbo calc

 

Engine is 3 litres w/ an aftermarket programmable ecu,current output is 340 hp,i'd build another engine for the project w less compression and port timing

 

What rpm range is it run in? What would you expect the lower compression engine with less port timing to make for power n/a? Any form of expansion chambers? A 3 liter 2 stroke is going to need a good size turbine if turning much for rpm at 340 hp n/a.

 

He is not turbocharging a vagina.

 

Wow, brutal responses. I had thought it was available for up to 500CC, but it was the EFI that I was remembering. Well, if you want EFI for it
http://www.ecotrons.com/2_Stroke_Small_Engine_EFI_kit.html

 

WHAT the HELL are you talking about?

 

n/a power probably would be 275-300 hp, max rpm is 7k. i currently have wolf efi. i was hoping to use something w/ a t3 flange, as the exhaust chest width isn't all that wide. the exhaust dumps into a common plenum. was going to cut it open and install a flange across the back, and probably install the waste gate into that same plenum, to make the install more compact.

 

here's a china deviant on ebay, bothers me about only one ball bearing?? its nice though that it is water cooled though http://www.ebay.com/itm/CXRacing-T7...Parts_Accessories&hash=item2578116d35&vxp=mtr

 

Wow, way out of it here, I was reading 500cc instead of HP. Sorry, feel free to resume overreacting.

 

AFAIK, a 3L two stroke will need roughly the same compressor needs as a 6.0L 4 stroke, but will need a much smaller turbine housing. Difficult to make that match.

I am thinking something like a big holset, HW40 or so, with a small (23cm?) housing. Maybe even a GT35 style T3/T4 turbo?

 

Compressor based on hp, and pressure ratio like anything else, and we are running in the heart of the map, but have cvt clutching so we can be at target rpm 90% of the time. We size the turbine on the same..... double the cc, and use that to get a ballpark ve number and go from there. I wouldn't even attempt a t3 flanged turbo on that many cc, we are running a t3 stage 3 .63 on a 130-140 hp n/a 700 cc @ 7800 rpm. If your turbine is small you will get very very good at swapping pistons. I'm building a 700 cc twin, and going to try a P trim t4. What is your intended rpm range... ?-7000rpm? Every thing we run has expansion chambers, and we are experimenting without them, but havent tested much yet.

 

Being 2 stroke you could possibly run a variable vane style ?? Due to some oil in exhaust ??
Back pressure would be an issue on 2 stroke iff too high..
Yes a 58 / 62mm turbo

 

power range would need to be 3500-7000 rpm. i just didn't want to get into a situation where it doesn't go into boost. i agree to some extent about treating the engine as a 6 liter 4 stroke, as a 2 stroke fires every revolution.

 

We need more info on this project. Load and gearing have as much to do with spool as turbo size.

 

There are many variables when turboing a multi-cyl two stroke. When running expansion chambers twin cyl's work well with a single pipe, but when going to a triple there is power to be had with an expansion chamber per cyl. The point i'm trying to make is that with a two stroke that has no exh valves, backpressure/reversion plays a huge role in how the system performs when working with multi cyl's. I'd almost be tempted to do a twin setup to avoid some of the complexity. I wondered about load too.... assuming the right prop should provide plenty of load.... but i'm not that knowledgeable when it comes to boats.

 

If you don't mind me asking what 3L outboard do you have that makes 340hp ?