Supercharged!

[More Power]

http://www.maximumdiesel.com/images/andyblomdahl.jpg

Jim,

We are running tests with one of our Hammerhead 300hp supercharged diesels in our test dually. Enclosed preview photo.

Best regards

Andreas Blomdahl
ANDY'S IMPORT & MARINEDIESEL SWEDEN AB
Metallgatan 6
S-26272 Engelholm
SWEDEN
www.marinediesel.nu (http://www.marinediesel.nu)

[nvmtnlion]

Oh my.. *drool*

[gmctd]

Nice work - excellent!

[rjschoolcraft]

If they haven't built in a means for charge cooling...forget it.

[ogrice]

0nly 300 HP..? What does it really push.?
Go with a Weiand 8-71 and it will look like the Road Warrior/ Mad Max.

[markrinker]

Looks nice. Can't see how they could possibly cool the compressed air charge RJ, but it shouldn't run as hot as a turbo'd 6.5 since its spun by a belt, rather than with hot exhaust gasses.

There are plenty of supercharged diesels used in semi trucks - how do they fare?

[rjschoolcraft]

Actually, most of the temperature rise comes from heat of compression. With 100% adiabatic efficiency, the compressor outlet temperature (T2) is:

T2 = T1 * (P2/P1)^.283

There is some difference of opinion in the literature on the exponent, but that's pretty close. This will give you the temperature as a result of compression alone. Divide that result by the efficiency to get the actual temperature rise.

Most centrifugal compressors operate between 65% and 80% efficiency, so:

T2actual = T1 + [(T2 - T1) / eff.]

Roots type blowers (like the one pictured) usually operate with less than 50% efficiency. Therefore, the charge temperature for a particular pressure ratio will be significantly higher for a roots type supercharger than for a centrifugal type turbo-supercharger.

My main comment is related directly to the 6.5, which seems to be very sensitive to charge temperature. I've never seen a belt driven supercharger on a semi, but then that's not really saying much.

Typically, boost levels with these systems are lower than with charge cooled turbocharged systems.

Edited to fix an error in the second equation.

[ 04-24-2005, 11:12 AM: Message edited by: ronniejoe ]

[dieseldummy]

Looks like another good option for the 6.5.

Those truck engines Mark is thinking of are probably the older 2-stroke Detroits. They had a roots type blower on them, but it was used mainly for a scavenging effect. They produced little to no boost pressures. Later on they added turbos to them for a power boost. The latest "silver" series had a bypass from the turbo around the blower to an IC.

[rjschoolcraft]

Now that you mention it, I remember seeing some of those old Detroits with roots blowers on them. They used to build those at Allison Plant 5 in Indianapolis. They were phasing production of those out as I started there in the mid 80's.

[EWC]

I'm pretty sure that is a screw compressor and not the Roots style . Different in the way the air is compressed inside the case , but the screw type has a lower temp for the compressed air and is more efficient .

[autocrosser]

In my working days we had a number of Detroit V12's with dual super chargers and dual blowers and no inter cooler. If you didn't have the blowers I don't think they would run very well. The turbos boosted the power.

They drove 175KVA generators for the lighting systems at airports. the reserve oil system for them was 30gal due to the huaranteed oil leaks. They leaked even if you did a total reseal job on the heads etc. I think all the old Detroits in trucks were like British cars. They were always marking their spot when they stopped

[grape]

that's one of the infamous 100hp at 1000 rpm monsters :rolleyes: maybe they've gotten around to changing their dyno sheet by now. That equals 525 ft. lbs. at 1000 rpm, I'll take one please, and straight to the superflow it goes and the BS stops.

[grape]

sorry for the mistake, their dyno sheet now shows 125 hp at 1000 rpm. hmmmmm that's 656 ft. lbs at 1000 rpm......cool :rolleyes:

[ 04-14-2005, 05:10 AM: Message edited by: grape ]

[Dvldog 8793]

Howdy
Way cool...
I have always thought that a blower takes power to make power??? Wouldn't that give turbos an upper hand in the HP department? Also I thought turbos were more reliable in the long run? I am probably dead wrong as you don't see many top fuel dragsters using turbos. Then again those monsters are a whole different ball game. I've alway thought that a 6.5 in a boat with H2O intercoolers and a twin turbo set would be really neat. I am sure with cooling capacity of a small lake you should be able to get 300HP???

Aint it fun to dream!!! :D
L8r
Conley

[grape]

turbochargers have been banned from pro classes in NHRA and IHRA.

[DmaxMaverick]

Originally posted by Dvldog 8793:
Howdy
Way cool........I've alway thought that a 6.5 in a boat with H2O intercoolers and a twin turbo set would be really neat. I am sure with cooling capacity of a small lake you should be able to get 300HP???

Aint it fun to dream!!! :D
L8r
Conley LIKE THIS??? (http://www.peninsulardiesel.com/trucks.htm)

[Cowracer]

Unless your first name is "Doctor" and your last name is "Lee", a diesel without the turbo whine is an insult.

[Peter J. Bierman]

since that truck is in Europe I will try to convince them to bring it to the Eurorendezvous in September.
I'll bring my Twin Turbo Blazer and we'll see :D

Peter

[Craig M]

All the Detroit 2 stroke engines (6-71,8V71 4-53 etcera)had blowers. They are part of the design for the two stroke system. Later they added turbos in front of the blowers (8V71T et al). The V-12 had two turbos because of the size. Current diesel truck engines are 4 stroke and use turbo's not superchargers.

[More Power]

Guys... I was going through some photo archives yesterday, and came across the above photo. Though it's a couple years old now, I thought you'all might be interested... smile.gif I didn't remember getting this one....

Peter, you also need to contact BETA, to see if they can attend. I can shoot Christer an email if you like. They are supposed to have a couple of aluminum headed 6.5's running that would make for some interest here.

MP

[Hubert]

Thanks for the picture it looks really cool! Keep us posted!

How does it drive normally?
light/heavy footed? Under load? Acceleration? Midrange? Top end? Economy? Sound? Maintenance? Longevity?

Are you running true duals and/or headers? What is the exhaust size and mufflers?

I have wanted someone with info on a supercharger to post. I have looked (dreaming) all around and no one makes a std off the shelf kit for the 6.5 anymore (I think EATON had one a few years ago). I understand the 6.5 is not really lacking in air to make power. There are other limiting factors to really build extreme power.

I think a supercharger would help an 18:1 pistoned engine crank better (but they don't have problems; maybe could go lower on compression with the supercharger).

A water/air cooler could be fabricated to help with the compression heat and the true duals and/or headers would sound great!

Some of the bias for turbo over supercharger is marketing perception and manufacturing cost. Pontiac has had success with the 3.8L supercharged engine. So it can be done.

I think I understand the advantages of super verse turbo are:

More boost at low rpm.
Boost somewhat more regulated with engine rpms. Its geared to motor rpm not load and how hot the combustion is (or how much it expands). I think this helps the HP/Torque curve more consistently through out the range.

Food for thought ... I have heard some firetruck engines have both turbos and superchargers working together! I guess they work kind of like the twin stage turbos and or maybe get the benefits of both driven input and Turbine power depending on load and engine rpms.

[Peter J. Bierman]

Jim, everybody that has something interesting to show or tell would be great.
Ofcourse we allready have Doc. Lee attending but never the less.

Please inform them or pass me the contact persons and adresses so I can contact them.
smile.gif

Thanks, Peter

[84 Convert]

The thing with the 3.8 supercharger is that it only puts out about 5 psi... not much heat with that kind of pressure change.

No lag with the supercharger is a big plus. Cost is a big minus. Also, with the lower efficiency of the roots blower, temps will be more of a problem. The screw type compressors are quite spendy from what I've seen.

Gregg

[Craig M]

A supercharger is run from the engine. It takes engine power to run the supercharger. The turbo uses the exhaust to spool up, essentially free power. If interested in good mileage and power the turbo is a good accessory. For pure power the supercharger is a fun add on.

[Uncle Wally]

More Power

What's this you mention of aluminum heads for the 6.5? Expound please.

Thanks,
Waldo

[ogrice]

I read the use of aluminum heads too. Who makes them.? Are they experimental or already out on the market.?
Maybe they are one of a kind components like what Lingenfelter did for a few super Corvettes. Somebody please explain.

[MarcHogenboom]

Graig, there is no such thing as a free lunch. Turbo's take power too by restricting the flow of exhaust gasses. It takes power to turn the wheel. Or maybe mr Mercedes is nuts, building Kompressor (supercharged) engines instead of turbo engines. I think they know how to calculate over there.

[More Power]

BETA produced two sets of aluminum 6.5 heads a couple or three years ago or so. The owner has access to a casting company that produces parts for experimental use. If what I remember is correct, BETA could offer these for something like $800 or thereabouts (don't hold me to that) a piece, and would consider offering them commercially if there was a sufficient market for them.

I told BETA that we wouldn't know what the market would be till a third party got a set and put them through a series of tests. That's where the discussion was the last time we talked about aluminum heads.

I should also mention that BETA was running two sets of them - one set was in a 3500 work truck that was always on the road.

MP

[AndyL]

If it was 2 or 3 years ago it is probably safe to assume the results were not great, or else he would have been gathering support for a production run.

Where has Beta been in the past year or so? I don't recall seeing any posts.

[More Power]

Andy, I wouldn't read too much into it. It's very expensive and time consuming to put a completely new and complex manufactured product into production. I think it's likely the "unknown" market factors (economic risk) have kept the aluminum heads where they are.

MP

[rjschoolcraft]

Originally posted by Marc Hogenboom:
Graig, there is no such thing as a free lunch. Turbo's take power too by restricting the flow of exhaust gasses. It takes power to turn the wheel. Or maybe mr Mercedes is nuts, building Kompressor (supercharged) engines instead of turbo engines. I think they know how to calculate over there. Roughly 1/3 of the thermal power potential of an engine goes into mechanical power at the crankshaft, 1/3 into heat load for the cooling system and 1/3 out the exhaust...

We Americans can calculate too. That third into the exhaust gets used to power the turbocompressor.

While there is some loss associated with running a turbocharger, it is much less than with an engine driven supercharger. Plus, as I mentioned before, the efficiency of the centrifugal compressor is much better than the roots blower...and even a lot better than a screw type blower.

The trade-offs deal with lag, configuration and other issues.

[Cowracer]

RJ is right about where the power goes. There has been many attempts to recover the energy wasted out the tailpipe

Some radial avaition engines at one time had a system called turbo-compounding. It used basically the hot end of the turbo, and fed the recovered power back into the crankshaft via gears and fluid clutches.

I think that Volvo experimented with that in commercial trucks not too long ago. Anyone who can find a way to recover that lost 1/3 would die a rich man

Tim

[MarcHogenboom]

There is no doubt in my mind RJ is right about where the energie goes, but if he is right in stating that the last third is used to drive the turbo, he must be that rich man you mention. I think the turbo is driven by the speed of the exhaust gasses, driven by heat and piston movement. Driving the turbo slows thes gasses down, and we all know this lessens the filling of the cylinder. All I mean is: there is no such thing as free power. It takes energy to make boost. The net outcome is what counts

[grape]

blowers are simple for simple people............People who like to make enormous amounts of HP and are not limited by rules, use turbochargers. In sanctioning bodies where turbochargers are still allowed to compete against blowers, they now have size restrictions on the turbocharger inlet wheel :rolleyes: . yet you can run any blower you want.

[rjschoolcraft]

Originally posted by Marc Hogenboom:
...but if he is right in stating that the last third is used to drive the turbo, he must be that rich man you mention. I think the turbo is driven by the speed of the exhaust gasses, driven by heat and piston movement. Driving the turbo slows thes gasses down, and we all know this lessens the filling of the cylinder. All I mean is: there is no such thing as free power. It takes energy to make boost. The net outcome is what counts
Originally posted by ronniejoe:
While there is some loss associated with running a turbocharger, it is much less than with an engine driven supercharger. Plus, as I mentioned before, the efficiency of the centrifugal compressor is much better than the roots blower...and even a lot better than a screw type blower.

The trade-offs deal with lag, configuration and other issues. I think it's clear...

Some of that 1/3 of wasted energy is recovered and put to use to run the turbocharger. Therefore, something less than 1/3 is wasted out the exhuast pipe. With a supercharger, none of the wasted energy is recovered... In fact, you have increased the parasitic loss above that of a naturally aspirated engine.

As I said before in a different way, a turbocharger adds some parasitic loss. The back pressure makes the piston harder to push up on the exhaust stroke. However, figure the torque required to overcome that pressure times piston area for the eight cylinders and compare that to the torque required to drive a supercharger. Throw in a stated operating speed and compare the power loss. What you will find is the turbocharger power loss is much smaller than the supercharger...plus the added benefit of reclaiming some of the otherwise lost energy.

The efficiencies of the compressors are also significantly different...as I said before.

Now, about being rich... I wish! :cool:

[EWC]

" blowers are simple for simple people " ???