Flat head supercharged

[Mickkc77]

On 1/20/2019 at 3:22 PM, 41/53dodges said:

Not a very extensive one, made some modifications since then. Eventually gave up on the fuel injection and went back to the carb. Turbo was particularly small, like off a 1.6l Subaru. Boost hit about 1200rpm and carried all the way to the top, but the issue was exhaust backpressure started countering the boost above 2500, kinda like a banana in the tailpipe.

 

That said, for super and turbocharging alike the exhaust is a big problem. Scavenging is deeply improved going to duals (read up on flat vs cross plane cranks for V8s for reference) Cleaning up the ports & combustion Chambers with a mild cam help as well. Basically, build a reliably strong N/A motor inside and out and build from there.

 

Probably should stipulate, If you're expecting V8 power then this is not the solution. It's not going to raise the motors redline, and the boost curve doesn't change the motors natural torque curve, only aids (and sometimes pulls it down)

 

Feel free to pick my brain if you please!

I'm by no means a wizard, although I do like pointy hats... 

 

How about a dual set up. They used to use the roots supercharger on the exhaust side of the old diesel motors to draw out they exhaust gasses and aid savaging. So do the same for the side valve 6. Then add a turbo to boost the intake.... Yes I know it'd be a plumbing nightmare, but depending on what car you have most of the 50's cars have huge engine bays and lots of space to spare. Just a thought for the mad scientist out there? 

[Plymouthy Adams]

superchargers unlike turbo chargers, take engine HP to create HP gains where the turbo effect is purely exhaust driven and basically has no robbing effect of the engine.  There are other arguments to consider also...both have their application.   VW did the dual setup...cost was great.  For a street car mod, the supercharger is often the easier to bolt on and tune.

[kencombs]

6 hours ago, Mickkc77 said:

How about a dual set up. They used to use the roots supercharger on the exhaust side of the old diesel motors to draw out they exhaust gasses and aid savaging. So do the same for the side valve 6. Then add a turbo to boost the intake.... Yes I know it'd be a plumbing nightmare, but depending on what car you have most of the 50's cars have huge engine bays and lots of space to spare. Just a thought for the mad scientist out there? 

If you are referring to the Detroit diesel, that description is not entirely accurate.  The supercharger blew intake air into the cylinders via passages and ports in the block. That routing was used instead of 'normal' practice with two strokes that use crankcase pressure to move the intake charge to the cylinder.  However, there is enough flow was available that it also used to push combustion products out of the overhead exhaust valve.    I loved the sound of a loaded truck with one of those old two cycle screamers!

[Don Coatney]

I once owned a truck with a 2 stroke Detroit 6V53 with a huffer. Tons of power. It would climb hills in top gear where my gas trucks had to down shift 2-3 gears. For a diesel it was a high revving engine.

[kencombs]

1 hour ago, Don Coatney said:

I once owned a truck with a 2 stroke Detroit 6V53 with a huffer. Tons of power. It would climb hills in top gear where my gas trucks had to down shift 2-3 gears. For a diesel it was a high revving engine.

High revving and and sounded faster because of the 2 cycle thing.

[Merle Coggins]

Ah yes, the old Converter Engines. They convert air and fuel into noise... They certainly have a unique sound, especially the 6V53’s. 

 

Interesting note on the 2 stroke Detroits, since the blower is a necessary part of the air intake system, as noted earlier, they are considered ‘naturally aspirated’ even with the blower (supercharger). The higher HP versions added turbos to boost the intake charge a bit more. The turbo feeds charge air into the blower intake. 

[Mickkc77]

10 hours ago, kencombs said:

If you are referring to the Detroit diesel, that description is not entirely accurate.  The supercharger blew intake air into the cylinders via passages and ports in the block. That routing was used instead of 'normal' practice with two strokes that use crankcase pressure to move the intake charge to the cylinder.  However, there is enough flow was available that it also used to push combustion products out of the overhead exhaust valve.    I loved the sound of a loaded truck with one of those old two cycle screamers!

Yeah that might be it. It was a long time ago when I was reading about them.

[48Dodger]

From the 9th annual Clements Tailgate BBQ 2016.....Steve is the owner and has an excellent website on how he built this truck.

 

48D