Putting a turbo on the ol' 1915

[madmike]

I found a nice Snow injection kit on FB marketplace brand new in the box for $125 if it ever quits snowing up here ,, i'll test it

[Therealkoop]

Yeah its staying pretty cold around here too, snow rain sun freezing.

I suppose I could also easily make a setup that uses a dual outlet, single inlet intercooler for simplicity sake. Ive already added way more complexity than I ever planned by going to this turbo setup. I imagine water/meth would be more effective, but the IC is a set and forget.

I forget that I have a holley blue fuel pump, so my fuel pressure is already getting close to max with boost reference. I wouldn't mind rigging up an A/A IC anyway, just for the extra safety margin on my current 10psi. Assuming I can make it look good that is.

[Therealkoop]

Some tests:

Moved the boost indicator to under the carb. It looks like my mod ring and carb combo are creating at least a 1 PSI pressure drop which seems reasonable. Im reading closer to 8-9psi under the carb versus the 10 psi at the charge pipe.

I set up a K type in the carb hat. I did a few full pulls, and my charge temps read about 165*F at the top of third gear which is about the highest load I can possibly muster realistically. The outside air temp is 60* today so in a normal 85* summer day I would expect the temps to rise linearly and be around 190f. Ive done a lot of testing with charge temps and this is usually what I experience. These temps are before fuel is introduced but I have no bearing on how much temp drop would be experienced after the carb. ACTUALLY while typing this, I thought of a way to probe it. Next time.

I also pulled off the exhaust which had baked off all the factory coating, and rattle canned it. While it was off I added a bung for exhaust backpressure testing using my boost gauge. A test for a different day.

Pulled the plugs, all look good with no detonation signals. Compression is 150psi on all 4.

[Clonebug]

I've spent a quite a bit of time working with IAT's.

If you have an ambient temp of 60* you will see between 10-20 degree increase just going through the turbo without boost. Your boosted temps are pretty close to normal according to the calculator I use so you are doing good.

Here is a nice calculator if you need one....if no intercooler use 0% as the intercooler efficiency.....

https://www.rbracing-rsr.com/intercoolers.htm

Anything over 130* I have found you have to retard timing which is giving away horsepower. It is well worth your while to either use Water/Alcohol injection or add an intercooler.
It's pretty easy to build your own water injection system using off the shelf parts. The only thing you will need to buy is the nozzles. They are not cheap though.
I upgraded to a "Devil's Own" 300 PSI pump and really don't see much gain compared to my el-cheapo $75.00 pump. For a 20 lb. boosted system....a Sureflo pump will work. Just crank it to 120 lbs.

Nozzles are based on hp and boost levels. For your 1915 at 10-15 lbs boost a 2.0gph nozzle would probably work.

I run two nozzles staged at 4.0 lbs and 9.0 lbs. It lowers my IAT's by 100 degrees.

[Therealkoop]

Sounds about right, I was seeing about 75-80 at idle and around 103 cruising at very light or no boost.

Thanks for the calc, pretty neat to screw with. Even if not 100% accurate it gives me a good relative idea versus my real world data.

Right now im running a max mech advance of 24 total degrees. That amounts to about 1* of retard per psi at this point, what kind of timing are you getting out of your setup?

I like the idea of water meth, but I am incredibly biased against adding more wires to my system even if its a good idea. What do you use as fluid for your water meth and where do you get it?

Im looking at standard A/A intercooler cores I might be able to add to my system with relative ease. I think it would be a good idea even without adding boost and Im curious to see how it affects the temps. Im also limited by my holley blue fuel pump which is internally regulated at 14psi and I would have to do something in order to run much more boost.

[Clonebug]

With your fuel pump you are really limited to about 10 lbs. boost.....You could run a stock pump and boost reference it quite easily. I ran over 13 lbs. boost with that setup. Anything over 11 lbs you need a programmable ignition retard and a good boost referenced fuel pump. The problem is once you get to that point you always want more......
Don't waste money chasing the boost.....just bite the bullet and pick up a MS-1 or 2 or even the off brand ones..... but if you don't do it soon you will find you are spending money that is better saved for the real deal.
You can always run ignition only and then someday....move up to FI.

Water meth is pretty easy....

A Hobbes switch...$25.00
A 2.0 gph nozzle $25.00 from Devils Own.
A Pump......your choice......$75.00-$140.00
A tank.....I used a craftsman lawnmower tank........free
1/4 inch hose and fittings
A couple bungs....I use black pipe 90's or tees and cut the threaded parts off for a cheap bung.
A relay...... $4.00
Some misc wire.....
If you ever go up in boost and need more water you can just add another nozzle and a Hobbes switch for a staged setup.

For fluid I buy Denatured Alcohol at my local "Ace is the Place" store for about $20.00 a gallon and add a gallon of Distilled water to it to make a 2 gallon batch. The Alcohol keeps going up in price...it used to be $16.95.
You can also use Methanol if you can find it but it is more corrosive than Denatured Alcohol.

As for timing it will depend on your IAT's.
I have IAT's of 70-90 Degrees at 24 lbs boost so I can run about 25 degrees timing at that level.

Without boost cooling you will be limited to 18-20 degrees if your temps get around 160 degrees. I saw detonation at 11 lbs boost especially in the summer with higher ambient temps. Spring, fall and winter was more forgiving due to lower off boost temps.

That calculator is pretty accurate.....in fact every one of the calculators I use from that website are very close to real world numbers.....at least I have found them to work on all of my stuff.

[Therealkoop]

Awesome thanks for the detailed response. Denatured alcohol makes the system more appealing since its readily available. It would add to the goofyness of my setup so im starting to warm up a bit.

The main reason I want to stay carbed/simple, is because I spend 8hrs a day tuning fuel injection stuff. Its fun to screw with and a unique challenge after 15 years of FI. The mod plates, carbs, mechanically limited dizzy, all fun things to do.

More fun than having more power? Well..........that is my current internal conflict.

[Schweg]

You can also use windshield washer fluid, and the yellow bottle heet de-water treatment.


https://www.homedepot.com/p/Krystal-Kle ... /202259351

That’s my go too, I spent a fair amount of time sifting through MSDS sheets finding a good cheap off the shelf option.

As for the components I can’t help i bought a used setup, and would rely on clones advice. Also I have a 3 gallon tank that is way to big if I had an option I would go 1.5-2 gallons if I was building it from scratch.

[Clonebug]

It's fun until you crack pistons due to detonation........I've replaced P/C's twice......the first time was for excessive blowby and the second time was because I had a session of severe detonation while showing off and refusing to lift off the throttle. I had some blowby but since I was about to go on a 3500 mile trip I replaced them just because.
Listen crefully for detonation...it sneaks up on you and sometime you don't hear it right away.
160 degree IAT's and 10 lbs. boost is right there......depending on ambient temps.......ask me how I know......

[madmike]

Carbs are fun, ya just have to stick to it,,,,,,,,,,,,

[Therealkoop]

Is there a complete kit you could recommend for my setup? Im dumb at water/meth so it probably would give me the best chance of success and avoiding multiple small orders. 2.0gph is my direction at the moment per your previous suggestion.

Also, how does spraying water/alky affect your AFR?

[Clonebug]

Gph is based on boost and targeted hp....Devil’s Own has a calculator to determine the nozzle size.
Wouldn’t hurt to punch in your engine size, boost and hp target.
I should add I have no W/I experience with a carb.
It’s going to richen up your tune due to the alcohol injected. FI will take out fuel to maintain a targeted AFR but I don’t know what happens with a carb.
Also... if you inject in a vacuum environment you need a capable solenoid. I forgot that in the parts list.

[Schweg]

Kits like that make it easy.

Though like clone said above a pump, tank, Solenoid and a Hobbs switch can get the job done.


Though it is going to play hell on tuning as it goes super rich.

Though they used to use it on P-51 so it’ll work on carbs.


Sent from my iPhone using Tapatalk

[Therealkoop]

Looks like a basic snow performance kit is shy of 300 dollars,which is what an A/A setup is going to cost me. Ill give it a go. Something new and interesting to tune with.

Yeah I thought it would go rich, although since the stoich ratio of meth/alch is different than gas it causes an AFR sensor to spoof to an incorrect number. Using FI I would be able to calc a ratio between the gas/meth/airflow and figure out what the stoich ratio should be, but I dont know how to figure how much fuel my carbs are dumping with no way to meter either air or fuel flow.

I figure I could get it figured out. Depending on when is normal to start injecting meth, I could probably remove the mod plates, or lean the air jets to achieve the target AFR. Leaning the air jets would help bring fuel in quicker at the lower boost levels also. I think I could get it to work well enough but getting rid of flat spots would be the hard part.

Looking at possible injection points. My turbo goes right into the splittier almost immediately. My first thought is option #1, right up the "buttcrack" and pointing directly into the incoming air stream.

83005309_10162869484570201_4611135197461610496_o.jpg

[madmike]

You can just screw it in the turbo too,remove brass plug