turbo outboard???

[warrior74z]

Look at this newspaper ad from the early 1960's for a gas turbine outboard. Not turbo or turbo-charged, which is a piston engine that uses exhaust gas pressure to force the air/fuel mixture into the intake/carb/cylinders.
Turbine is a product of an aircraft jet engine, and has no pistons, but uses compressed air and fuel that is ignited and spins the blades on a shaft at very hight rpm and must be recuced to a useable shaft speed for prop use.
I am not an expert by any means, but feel that a lot of people think turbo and turbine mean the same thing but are totally different animals.

Post number 6 shows a turbine outboard. Now that is really something.
I doubt this old ad engine was sucessful but shows how long ago it was tried.
Barron

[ct20sutphen]

Damn I shouldnt have seen this one.
I am a huge turbo freak and I have raced a 69 firebird with a 468 and a T88 turbo for many many years.
I was think recently if I had only gone I/O I cold have turbo'd it.
I guess I could do that to my carbed 2.5 200's Just knock down the compression and boost it.

[Buckman_4]

Tom Airhardt (not sure it is spelled right) did the twin turbo thing alot, he used to run the miss budwieser snomobile all powered by merc v-6 with twin turbos. i think he has several of them on boats too

[JrCRXHF]

Turbo nut here too

boosted 600cc GSX-R rocket motor

Turbo CRX B16 (on E-85 or pump gas)
Plymouth Laser RS Turbo AWD standalone AEM EMS with rally anti-lag (E-85 or pump gas)
Mitsu EVO IX MR


would love to boost a V8 omc with fuel injection the problem with carbs is that if something starts to go wrong the motor can run aways from you because the fuel just keeps getting drawn in.

With EFI the computer will shut stuff down and save the motor but i would think it would cost around $8,000 to turbo a OMC V8 right. Just not worth it on my pocket book.

but a nice GT 35R with 8 600cc injectors and E-85 for charge cooling would be perfect.

[STV_Keith]

Not nearly enough air from a 35r, and I wouldn't think a V8 would be the place to start (not nearly as reliable as the Mercs, especially making big power). Cool idea though.

[JrCRXHF]

Well it depends on the CFM the motor does stock. The idea with the 35R is a quick spooling turbo with around 850 CFM at 14.7psi. This turbo with a nice intercooler will run around 30-35psi with still good returns.

If you went to a 37r i think you would lose to much down low and have a harder time getting out of the hole.

Just idea's tell someone trys it.

[STV_Keith]

Still way too small.

[Cobra1racer]

I recall seeing a picture of a V8 Rude with a blower on it. I think it's in Havasu.

[JrCRXHF]

how much air does a stock 4.0 move at 6700rpm does anyone know for sure.

[Mark75H]

how much air does a stock 4.0 move at 6700rpm does anyone know for sure.

No one probably knows the exact cfm, but a good guess would be around 80% to 85% of 4 liters times 6700, (twice as much as a 4 stroke would pump)

comes out to 804 cfm ... the 35r sounds like the place to start

[STV_Keith]

Thing is, you have to plan on how much CFM the turbo has to supply for the power you're going to make. If it takes 800cfm to make stock power, how much more CFM (and therefore bigger turbo) do you need to make more power.

[JrCRXHF]

for quick spool i like to look at what the turbo makes at 1bar or 14.7psi.

the closer i can get that to what the motor will make on its own i know i am going to spool quick. The 35r will flow much more then at 30psi to make up the difference.

The problem with a boat is if you can't get out of the hole or get the rpms up you will never see the turbo. Unless you spool with NO2. The real way i think to do it would be to gang the turbos and then be able to shut off the little one once you get up on rpm's so you don't have the back pressure.

kinda like this.

[Mark75H]

Yeah, that should work ... but it is as big or bigger than the original motor ... doesn't work on an outboard

[zx185]

thats how stock supras where, small turbo to spool the larger, but yes nitrous would be the way to get out of the hole. thats what we do on the cars with large turbos, shoot some spray on the line to build boost out of the hole.

[STV_Keith]

the closer i can get that to what the motor will make on its own i know i am going to spool quick. The 35r will flow much more then at 30psi to make up the difference.

The problem with a boat is if you can't get out of the hole or get the rpms up you will never see the turbo. Unless you spool with NO2. The real way i think to do it would be to gang the turbos and then be able to shut off the little one once you get up on rpm's so you don't have the back pressure.

I have seen GT35r's with inducers from 56 to 62mm, so there is quite a selection. That's still too small for an OB. You have to consider, compared to a 4-stroke engine, you are pumping 2x the air through the motor. So, you consider it a 2.5l motor that turns 2x the RPM or consider it a 5.0l motor that turns standard RPM (8500ish). That takes a big turbo to suppor that.

Also, there is no way to "shut off" the little turbo. That is called compounding though. The exhaust typically goes through the little turbo first, then to the big turbo. On the intake size, the big turbo sucks in the fresh air and pushes a certain amount of boost through to the inlet of the smaller turbo. The pressure ratio stays the same for the smaller turbo, but since pressurized intake air is coming in, it adds even more boost.

Here's a setup we ran on our diesel drag truck. T98 blowing into a T64. 150psi of boost. The big turbo only made 25-27#, and the little guy upped that a bit.