Using a Multifuel turbo on a gas engine

[Gunfreak25]

Just wonderin, has anyone tried using the Multifuel type turbo on another application? I mean, what makes a diesel turbo different from a gas engine turbo? As I understand it, the only things that make them different are air flow ratings. Obviously diesels will use a **** of a lot more air than most gas engines ever could. How would the Multifuel C turbo work on say, a low revving big block gas engine? I think the air flow would be just fine, the biggest issue would be fabricating the connections for everything as a Quadrajet carburetor was obviously never designed for a big honkin turbo. What would one get out of this? From what I have read the turbo on the Multifuels was nothing more than a "clean air kit" and was designed to reduce the amount of "nasty black smoke" emitting from the stack. Please correct me on the above if I am wrong......

 

[jimk]

The clean air kit was intended for smoke reduction however if there is available fuel there can be big increases in power, manifold pressure and EGT's. The IP needs to be set correctly for the desired effects.

It is very unlikely the C turbo would be suitable for a similar gas engine. One example is the compressor air flow requirements. The LDT displaces 478 cu inch. Air flow at redline(2600rpm) would be about half that of a big block Chevy(454 cid) at 5000rpm. That's assuming the volumetric efficiency is the same, which it is not. Even if the same compressor could put out twice the air flow (unlikely) it would produce boost inefficiently making the too air hot That decreases density, increases EGT's and promote detonation... all nasty. The higher exhaust gas flow may overspeed the turbine or the turbines nozzle may a restriction raising egt, restricting rpm, and lowering output .

The turbo must be carefully designed around the engine. The gas engine also needs to be designed around its turbo. Lower compression, wider exhaust valve seat, stronger intake seat pressure, less cam overlap, different timing and fuel curves...

Maybe twin C turbo's would be a start on a 8:1 c/r 454 project. The first place to start is finding a compressor maps for the C turbo used, comparing that with the math on how much airflow the engine of choice needs (operating environment, rpm range, volumetric efficiency...).

If you do go to the time and expense of building a turbo based gas engine it would be kind of silly trying to save a few dollars by using a recycled ex-army diesel turbo.

 

[Gunfreak25]

Now that's an answer, I had no idea there was so much involved in turbo's. Was just curious is all, thanks for the post.

 

[wreckerman893]

A turbo-charged gasser deuce (using the orginal engine) would be cool. Especially using a whistler turbo.

Maybe in a rat rod application.

This is a job for someone with more time and money than me.

 

[tigger]

Yep just get ya a redneck modification adapter kit!

 

[big block 88]

You could change the impeller wheel to a more aggressive design more suitable for gas application, but... that would cost money and a used turbo for a gas application can be had for close to the same $$$.

I've been thinking of doing twin whistlers on my Duece with a custom intake, not sure if the head gaskets would like it though.

 

[natem]

Yep just get ya a redneck modification adapter kit!

Ya need more duck tape ta make tat wark!

Nate

 

[tigger]

Ya need more duck tape ta make tat wark!

Nate

The duck wouldent give it back!

 

[natem]

A turbo gasser would be cool. Might even get a little better fuel mileage.


Nate

 

[wreckerman893]

Might even get a little better fuel mileage.

Downhill, in neutral, with a tailwind.........maybe.

 

[mktopside]

Quick answer is "No". Most diesel turbos don't have the same type of oil seal on the compressor backing plate that is needed to prevent manifold vacuum from sucking oil from the center section, when the engine is running in vacuum. I don't know the construction of the turbo on a deuce, but I know for a fact if you put a Holset HX35W on a gas engine it'll fill the intake with engine oil.

Each turbocharger is different. Garrett/air research/turbonetics builds their turbos the same across the board, so does IHI and Mitsubishi. Holset does not, Borg Warner does not, I don't know who's turbos CAT uses but I bet they don't either.

Turbos are more complicated than the engines they attach to.

 

[natem]

Ok that I understand.

Nate

 

[yamabro]

Not a good idea

 

[Coal Cracker]

while this may or may not be relevent, it's a c-turbo that is a gas engine ,,, lpg gas that is.

YouTube - homemade jet engine

 

[AR MOG GEDDON]

I know this is a month old thread, but here's my gasser with a turbo. I run 6 PSI on pump gas. T-3 turbo off an Isuzu diesel, and a 650 holley. I haven't checked the gass milage yet, but now I can stay in 5th on most of the hills around here. I'm working on a cummins for it, but that will most likely take another couple of years or so to do.

 

[Gunfreak25]

Holy moly, is that original 336 in there?

 

[mightymanx]

Ok I'll chime in.
I am a turbo guy I have turbo diesel trucks I run a 9 second turbo race car and I have made several turbo kits in my day so I know a small amount on the subject. I am not joking about small you could spend your entire life on turbos and still die a rookie.

First the only thing the Deuce turbo is really good for is scrap metal as far as a functional turbo goes. It was designed with WW2 technology (yes they had turbos in WW2) and it is so inefficient it pains me.

The modern turbo is orders of magnitude more efficient than the stock deuce turbo. And the T-6 size is way to big to be useful a modern T-6 turbo is used on HUGE engines (like too big to fit in cars huge)

So if you want to turbo a gasser there are a few things you deed to decide and the first one is Blow or Suck.

What I mean by that is where is your fuel source in relation to the turbo?

In a Blow through turbo the compressor output is going to blow through your fuel source (Carb fuel injection, direct injection whatever)

In a draw through system the compressor intake is going to suck on the bottom side of your fuel source.

Each has their own advantages and disadvantages I run both types of systems blow through on my Deuce and Dodge and draw through on my racecar.

Now you just cant plunk a turbo down on either application and make it work

A draw through turbo needs a "carbon seal" in the compressor section this is a ring made out of carbon sitting on a spring they use carbon because it is fuel resistant. A carbon seal turbo can be used in blow through.

A blow through turbo uses a "dynamic seal" which is a fancy way of saying O-ring they don't hold up to fuel so you cant use it on a draw through.

So you say why not use a carbon seal all the time? Well they are extremely fragile like 1 backfire it's broken fragile. And they are expensive to manufacture and install I change the carbon seal in my race car about 5 times a season to the tune of $40 each and I do my own turbo work a shop will charge you about $150.

Now boost is the most misunderstood thing around so I am going to KISS explain it.

14.7psi = atmospheric pressure so right now at sea level the air weighs 14.7 psi (got it)

A naturally aspirated engine can only draw enough air to at best equal 14.7 psi it cannot draw more molecules it can't pack air it is based on a vacuum.
The engine size is based on the volumetric displacement of the cylinders this becomes important in a minute.


A turbo or supercharger packs air into an engine.

The engine is going to draw 14.7 psi. If the turbo making 14.7 pounds of boost it is packing in another 14.7 psi into the engine EFFECTIVLY DOUBLING THE VOLUME OF THE ENGINE!!!!!

So it is the same as having a naturally aspirated engine that is twice as large.

Now to add some mud to a cloudy subject you have to work about detonation aka pre-ignition if a turbo packs to much it will detonate and the pistons crack rods bend all kinds of bad stuff happens.

With the very early turbos this could not happen because they were basically junk and could not make enough boost to hurt the engine you would have to spin the engine past redline to do that (sound familiar?)

Now a turbo from 1970is onward got much better so it could make boost far in excess of what an engine could use at MUCH earlier in the engines power band Some of the most modern turbos make boost at idle.

To control all this newfound pressure they created a pressure relief system called a waste gate it senses compressor pressure and then opens a relief valve in the turbine (exhaust) side causing the turbine wheel to slow down due to lack of driving force. This limits how much the compressor can pack air.

So you can now modify the turbo output to regulate how much power you can make simple right?

Well not really you need an engine that can take that newfound power so this is why the modern diesel engine is designed to live on boost the entire time. 60+psi of boost is not uncommon in modern big diesels. Now gas engines cant do that because of the flash point of the fuel my race car has a engine compression ratio of 8-1, I run 20 pounds of boost now to keep my engine from detonation I have to run C-16 race fuel (about 125 octane)

Now what happens when the Deuce owner ups his fuel to make boost. He is increasing the fuel to the point it all does not get burnt inside the cylinder and combustion/expansion happens in the exhaust system this WILL drive the turbine wheel faster but it really is making the turbo a bad jet engine. This is why you see a super spike in EGT's when you start making big boost on the stock setup.

To make boost the right way you resize your turbo regulate that output to your desired level through the waste gate then add fuel to cool off the EGT’s On my dodge if I up my boost the engine gets leaner on the Air fuel ratio and the EGT's climb I need to add fuel to cool it back off. Now to help things out you can cool the compressor air because packing air gets hot which contributes to detonation and hotter air has less molecules than cold air so compressed cold air makes better combustion. This is why all modern turbo vehicles have an intercooler to cool the compressed air.

So this is about .000000000000001% of known turbo knowledge I recommend looking up Corky Bell and reading his stuff because there is way more to know but by now your head is probably swimming with stuff.

And to answer the OP's question, "no it's junk and you would make no boost that would be useable"

 

[AR MOG GEDDON]

Holy moly, is that original 336 in there?

Well it's the original 331 REO.

 

[wdbtchr]

Ok I'll chime in.
I am a turbo guy I have turbo diesel trucks I run a 9 second turbo race car and I have made several turbo kits in my day so I know a small amount on the subject. I am not joking about small you could spend your entire life on turbos and still die a rookie.

First the only thing the Deuce turbo is really good for is scrap metal as far as a functional turbo goes. It was designed with WW2 technology (yes they had turbos in WW2) and it is so inefficient it pains me.

The modern turbo is orders of magnitude more efficient than the stock deuce turbo. And the T-6 size is way to big to be useful a modern T-6 turbo is used on HUGE engines (like too big to fit in cars huge)

So if you want to turbo a gasser there are a few things you deed to decide and the first one is Blow or Suck.

What I mean by that is where is your fuel source in relation to the turbo?

In a Blow through turbo the compressor output is going to blow through your fuel source (Carb fuel injection, direct injection whatever)

In a draw through system the compressor intake is going to suck on the bottom side of your fuel source.

Each has their own advantages and disadvantages I run both types of systems blow through on my Deuce and Dodge and draw through on my racecar.

Now you just cant plunk a turbo down on either application and make it work

A draw through turbo needs a "carbon seal" in the compressor section this is a ring made out of carbon sitting on a spring they use carbon because it is fuel resistant. A carbon seal turbo can be used in blow through.

A blow through turbo uses a "dynamic seal" which is a fancy way of saying O-ring they don't hold up to fuel so you cant use it on a draw through.

So you say why not use a carbon seal all the time? Well they are extremely fragile like 1 backfire it's broken fragile. And they are expensive to manufacture and install I change the carbon seal in my race car about 5 times a season to the tune of $40 each and I do my own turbo work a shop will charge you about $150.

Now boost is the most misunderstood thing around so I am going to KISS explain it.

14.7psi = atmospheric pressure so right now at sea level the air weighs 14.7 psi (got it)

A naturally aspirated engine can only draw enough air to at best equal 14.7 psi it cannot draw more molecules it can't pack air it is based on a vacuum.
The engine size is based on the volumetric displacement of the cylinders this becomes important in a minute.


A turbo or supercharger packs air into an engine.

The engine is going to draw 14.7 psi. If the turbo making 14.7 pounds of boost it is packing in another 14.7 psi into the engine EFFECTIVLY DOUBLING THE VOLUME OF THE ENGINE!!!!!

So it is the same as having a naturally aspirated engine that is twice as large.

Now to add some mud to a cloudy subject you have to work about detonation aka pre-ignition if a turbo packs to much it will detonate and the pistons crack rods bend all kinds of bad stuff happens.

With the very early turbos this could not happen because they were basically junk and could not make enough boost to hurt the engine you would have to spin the engine past redline to do that (sound familiar?)

Now a turbo from 1970is onward got much better so it could make boost far in excess of what an engine could use at MUCH earlier in the engines power band Some of the most modern turbos make boost at idle.

To control all this newfound pressure they created a pressure relief system called a waste gate it senses compressor pressure and then opens a relief valve in the turbine (exhaust) side causing the turbine wheel to slow down due to lack of driving force. This limits how much the compressor can pack air.

So you can now modify the turbo output to regulate how much power you can make simple right?

Well not really you need an engine that can take that newfound power so this is why the modern diesel engine is designed to live on boost the entire time. 60+psi of boost is not uncommon in modern big diesels. Now gas engines cant do that because of the flash point of the fuel my race car has a engine compression ratio of 8-1, I run 20 pounds of boost now to keep my engine from detonation I have to run C-16 race fuel (about 125 octane)

Now what happens when the Deuce owner ups his fuel to make boost. He is increasing the fuel to the point it all does not get burnt inside the cylinder and combustion/expansion happens in the exhaust system this WILL drive the turbine wheel faster but it really is making the turbo a bad jet engine. This is why you see a super spike in EGT's when you start making big boost on the stock setup.

To make boost the right way you resize your turbo regulate that output to your desired level through the waste gate then add fuel to cool off the EGT’s On my dodge if I up my boost the engine gets leaner on the Air fuel ratio and the EGT's climb I need to add fuel to cool it back off. Now to help things out you can cool the compressor air because packing air gets hot which contributes to detonation and hotter air has less molecules than cold air so compressed cold air makes better combustion. This is why all modern turbo vehicles have an intercooler to cool the compressed air.

So this is about .000000000000001% of known turbo knowledge I recommend looking up Corky Bell and reading his stuff because there is way more to know but by now your head is probably swimming with stuff.

And to answer the OP's question, "no it's junk and you would make no boost that would be useable"

I scared, I could actually follow what you are saying. Maybe I'm just having a stroke.

 

[goldwing2000]

To make boost the right way you resize your turbo regulate that output to your desired level through the waste gate then add fuel to cool off the EGT’s On my dodge if I up my boost the engine gets leaner on the Air fuel ratio and the EGT's climb I need to add fuel to cool it back off. Now to help things out you can cool the compressor air because packing air gets hot which contributes to detonation and hotter air has less molecules than cold air so compressed cold air makes better combustion. This is why all modern turbo vehicles have an intercooler to cool the compressed air.

I was with you right up until this point. If you're talking about a gasser, then your statement is 100% correct. Lean = hot, rich = cool. But as you alluded to, a gas engine is always trying to run at 14.7:1 A/F-R (stoichiometric mixture).
Diesels work the opposite. Adding boost to a diesel without adding fuel leans out the mixture and makes it run cooler. Adding fuel without adding boost will spike your EGT.
More fuel = higher EGT, more air = lower EGT. And diesels run just fine anywhere from 90:1 on down to about 15:1 A/F-R. Below 15:1 it will still run but you start to make lots of smoke.

At least that's how it works on all of the military diesel engines that I do calibration and development work on every day. Maybe the LDT is different.