Hello guys!!

Just wondering a little bit about a 617 turbo engine. What do you think about replacing the turbo with a belt-driven supercharger? Maybe from Powerdyne or Procharger....

I mean, with the turbo, you have as a main issue the intake air temperature, because the turbo body is heated by the exhaust which ends up heating the intake air added the heat generated by the compression of the air itself. This means you need a big intercooler when you are running high pressures.

Also you have the problem of the excessive heat accumulated in the exhaust manifold, which overheats the engine head.

My idea is removing the factory turbo, installing a supercharger and a ceramic exhaust header.

The supercharger will allow me to run a higher pressure with lower intake air temperature, added to the ability of the supercharger to produce boost is a shorter time than the turbo. I think this will eliminate the lag.

Also, the exhaust header will produce increased exhaust gases flow, reducing the engine head temp, which will also allow me to run a higher pressure.

Those are my thoughts. Any idea or comment?

Thanks

That would be cool! EMD Locomotives have a supercharger and a turbo. Supercharger gets 'em rolling, turbo keeps 'em rolling. No turbo lag either.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

a few problems could be from the low RPM of the diesel motors, special pulleys would be needed to overdrive the SC. also, the exaust gasses don't heat the intake as much as you would think, mostly it's the compression of the air itself. SC's will need an intercooler just as much as a turbo.
I have a procharger I have been thinking about using, but the pulleys are setup for cars turning over 6000RPM at WOT... with our 4K limit, I was thinking it might not work as well as the turbo now in place does...
John

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

thanks for the comments guys

vstech, you're right about the lower rpms but that's part of the challenge. about the gasses temp, my main concern is that when you have the turbo, there's backpressure in the exhaust manifold which means lots of heat staying there, which puts your engine head and valves in risk. I agree with you about the IC, but I think that a supercharger will allow the use of a smaller one, which is specially good for the W123 little room.

its been done



drool

Extra air mass from a supercharger or turbo will do little good without some additional fuel. The MW (the IP on USA verisons of the 617) pump is limited to the output of the delivery elements that are installed since no larger ones are available. Mods for more boost should include a modified type "M" (as seen in the Finnish beast above) pump from Myna in Finland. The M pump has a wide range of elements available.

__________________
Never a dull moment at Berry Hill Farm.

Diesels aren't as sensitive to back pressure as gas engines. Yes a reduction in back pressure is good, however recovering the energy wasted in blowdown during the exhaust cycle is better.

A blower would be better off the line but not in terms net power.

__________________
green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png

You're right about the fuel, I already had in mind the IP mods that will be needed.

So, what do you think of the supercharger/exhaust headers combination?

Turbochargers are more efficient than superchargers. The only reason to use a supercharger is packaging requirements such as the turbo just won't fit or you are going for the classic look like a 871 blower on a 454 chevy in a hotrod. Correctly setup turbos will always make more power than a blower. It simply takes more energy to drive the supercharger. RT

__________________
When all else fails, vote from the rooftops!
84' Mercedes Benz 300D Anthracite/black, 171K
03' Volkswagen Jetta TDI blue/black, 93K
93' Chevrolet C2500HD ExCab 6.5TD, Two-tone blue, 252K

There are a few problems with your logic.

First, Powerdyne or Procharger are the worst superchargers you can possibly choose. Centrifugal superchargers have the WORST features of turbos and superchargers. Boost lag, high intake temperatures, loud noise, and parasitic power draw from the crankshaft. If you must choose a supercharger, use a Roots blower or twin screw type.

Second, Most of the heat is from actual compression of the air, not from the heat in the turbine section. Superchargers heat the air just as much as turbos.

Finally, superchargers take actual horsepower from the crankshaft. Turbos only cause minor backpressure that translates to about 1/3 the power that a supercharger needs.

Take a look at this article: http://www.superchevy.com/technical/engines_drivetrain/induction_poweradders/0510sc_theory/

how about supercharging the 616? been thinking of it even if it was only for a marginal gain..

thanks.. i just splurted orange juice all over my wall....

Lets see. 68hp stock- 30hp to drive the SC + 20hp from boost after IP adjustment = 58hp.

Any links to specific and informative 617 mods? I did not know other pumps could be used. Tell me more.
This sounds like fun.

__________________
Thank You!
Fred
2009 ML350
2004 SL600
2004 SL500
1996 SL600
2002 SLK32
2005 CLK320 cabrio
2003 ML350
1997 C280 Sport

http://schumanautomotive.com/forums/forumdisplay.php?f=19