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You guys are missing the point I think. It's not about which is more efficient. The statement made was that somehow 1000hp form a turbo setup was less stress on the motor than 1000hp from a supercharger if I read it right. That doesn't add up to me.
Go give those videos by Richard I linked a watch when you have some time.
It is about efficiency.
It seems that because the turbo can create the same boost more efficiently you reach the same HP level with less boost on the turbo than with the SC--or the other way to interpret the result is that at the same boost level the turbo setup will be making a higher net HP.
If it takes 24lbs of boost to reach 1000hp with a SC, but the turbo can reach 1000HP with only 20lbs of boost, that's a lot less stress isn't it? (Plus you've got more room to go--once the turbo reaches 24lbs now you're well above 1000HP at what was the same stress level that only got you 1000HP with the SC).
 

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Discussion Starter · #42 · (Edited)
Mush's shop closed up FYI. It's a tough business.

As for the OP question, I think it boils down to what your "service" provides. The general contractor analogy is a good one. Back when I had my old Challenger built I researched several performance shops, interviewed them via phone, etc. My main criteria were reputation and one throat to choke. Several shops had motor built by company A, installed by company B, and tuned by company C. That's a good way to end up with a headache if there's a problem and the finger pointing starts.

The shop I chose in the end did everything in house from building the motor, install of everything, and tune by their in house tuner. They were also able to do it for less than I could myself by the time I had parts shipped, my personal time, finding a tuner, etc. Entire build was completed in 4 days and I drove the car home halfway across the country. If there was a problem they could only point the finger at themselves. O'l Orange Krush is still running strong and now resides in Germany believe it or not.

If @Cheapokitty plans to provide that type of service on this kind of build I think those looking for a TT setup would find value in that. One stop shopping and one person the customer goes to for any problems.

I do have a question. How is a 1000RWHP TT build easier on the stock motor than 1000RWHP from a supercharger? The engine just sees 1000+HP it doesn't know how that's being provided right?
Speedy the GOAT, what's up man.

Yes that would be the service I would provide, one stop shop or one throat to choke as you said, lol.

As for the power delivery, supercharger place strain on the motor by using the Crank to spin the blower. I'm sure you are aware of parasitic loss which in the case of these hellcats seem to be worth 80whp loss.
With Turbos there is no parasitic draw off the motor so it can freely spin and operate to its full potential gaining back any lost power. So 1000whp dyno from a supercharger is working the motor at a 1080whp+ rate where-as Turbos are letting the motor sing at 1000whp.
 

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Discussion Starter · #43 ·
Lol you guys took my question down a rabbit hole but the question still stands. How is 1000hp from turbos or a supercharger any less load on the internal engine components?
The Crank has to turn the blower and support the force of the rotating assembly pushing and pulling on the Crank. That's two points of stress on the crank.

Now let's talk cylinder pressure and temperature. At stock boost levels (12lbs) and stock timing your engine is operating at a low stress level. The cylinder temps will be low and you are keeping the pressure against the pistons, ringlands and rods lower. Now go ahead and add a 2.75 Pulley which will now generate 15lbs of boost which will also increase cylinder pressure along with the components of your engine. Remember boost is only a measurement of restriction.
Now let's say you want to reach 1000whp and to do this you add a bigger blower and increase the boost to 22lbs. You have DOUBLED the pressures in each cylinder which will require more fuel which will require more aggressive timing. The increase in pressure and heat is a recipe for detonation risk, which I'm sure you know is motor killer.
I can tell you that my turbo setup on a stock motor car will reach 1000whp at 17-18lbs of boost. That 4psi delta is relief to your cylinders, Pistons, ringlands, fuel system and now we can talk about the Crank not also spinning a blower. Cylinder heat will also be down and help control detonation. The Turbo setup will reach your goal of 1000whp with less stress on the motor.
Now I have a 426 forged bottom end with a custom grind comp cam which makes 1000whp at 16lbs of boost and 12 degrees of timing. I can make 1000whp on 93 Pump gas which blows my mind but that's the cool part about turbos.

Does this make sense?
 

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Fair enough, BUT, what would make a customer want to go to you over a top reputable shop, even if they do other mods as well? Reputation matters to many people since people have been burned by smaller shops. I'm certainly not implying you're not reputable, but it does take years to build a good reputation which is going to take time.
I agree 100% that about your reputation comment but reputation's can also be repaired. I can prove this by using John Hennessey as my example. He BURNED the Corvette and Viper crowd to the ground and now has come back to build some high dollar modded cars that perform well and seems to have a thriving business.

My best suggestion pretty much parrot's what you (Blkout) said and treat people right the first time around because Folk's are trusting you with (what I consider) a large amount of money and just because you made one fast car, doesn't mean that you can consistently do it again. You have to prove that and the first couple of builds are paramount for you to get your rep established.

In all Honesty, I wouldn't automatically trust you because you've got many followers on Youtube. They mean nothing to me because I don't know them and I don't know you! Trust needs to be earned over time and results. You treat people right and they usually respond in kind!

Sorry to be a buzzkill too but I'm skeptical by nature and it's just how I think! :)

PEACE!

Nope just doesn’t work that way. Turbos do create an exhaust restriction, but as long as they are properly sized they are almost totally free HP spun off spent exhaust gas. Blower is hard on crank, front drive, takes away power via crank, and PD blowers in general are harder on lower end due to the torque curve they favor. Go spin a turbo blade, then spin a roots blower one revolution, you will understand better.

Go watch engine masters and you will see the comparison you’re looking for. Most here already understand blowers strong points and weaknesses so it doesn’t need to be covered again in regards to making HP. PD Blowers win down low, turbos win up top. General statement…
In actuality, turbo's are the restriction. They just eliminate parasitic drag over a blower. A turbo will slow down the exhaust speed until it comes out of the compressor side of the turbo, then it's not a restriction anymore. It's kind of like the old Hotwheel's Supercharger that you put on the track when playing with your Hotwheel's cars. The car is slowing down as it comes between the wheels and then the spinning wheels of the supercharger grab the sides of the car and "Boost" it out of the other side.

The exhaust is the car coming in and the "Boost" is it coming out.



You’re missing it though. Exhaust is coming out no matter what if it’s an ICE engine. You’re using the exhaust as the source of work to create positive pressure instead of turning something with mechanical force off the engine. As I said I don’t want to call it totally free HP, but based on my experience it’s close enough to free to call it that.

I took thermodynamics in engineering school. You’re 100% right but looking at it wrong. The exhaust coming out of an engine is capable of tremendous work but isn’t always taken advantage of. That’s all this is…

Blowers spin around 17k RPM. Turbo will spin over 90k RPM. Totally different scenarios because turbine wheels weigh nothing compared to the rotor set in a blower. You’re looking at it as you’re trying to spin a heavy thing to create boost off exhaust gas when turbos in fact are amazingly efficient.

There is a downside. Some of the guys don’t get any downforce out of zoomies or blow horns on the fastest twin turbo cars in the world. The blower and nitrous guys get measurable downforce out of their zoomies on the same cars. That’s only because the exhaust lost its energy in the turbo instead of getting wasted. Or used in this case haha
The downside to downforce is that it creates drag to and can slow a car down. Everything has a compromise and things depend on what you're trying to accomplish. If it were a road course, then downforce is beneficial. On a drag strip, not so much because it's more about weight transfer than aerodynamics. Granted, a slipperier COD (Coefficient of Drag) will help on top, but that's not downforce.

Lol you guys took my question down a rabbit hole but the question still stands. How is 1000hp from turbos or a supercharger any less load on the internal engine components?
No belts and/or crank pulley hanging off of the front of an engine. Crank snout isn't subjected to a belted pulley trying to spin off of the front of it. For some reason, turbo's seem to be easier on engine parts just because of how the boost is delivered. It's less violent but more efficient. If that makes any sense (it does in my little peanut head but sometimes I lose things in translation:( )

Of course Richard Holdener comes through for us with a great, thorough comparative demonstration. And yet another he did is also very informative.

I don't think it's fair to say that turbos have no parasitic loss--that's simply hand-waving. They of course cost power, just like a stock manifold costs power vs long tube headers--they are probably at least costing power within the same order of magnitude--but much less in total than a SC does, because the answer seems to be two-fold:
1) the actual pump mechanism of roots or twin-screw is less efficient at moving air/creating pressure than a turbo rotor
2) the turbo boost curve can come up much earlier in RPM whereas with any of the 3 SC styles it is always strictly linear with RPM

In another thread here someone brought up the fact that some people are also running compound boost setups--to get the best of both worlds. That would probably be a whole lot more variables to juggle.
I agree with number 1 but disagree with number 2. A PD (Positive Displacement) or TS (Twin Screw) blower isn't linear in power and will usually beat a PROPERLY sized turbo in the bottom end power department. You can undersize a turbo to pick up on the bottom but you'll overboost on top unless you have a sequential boost setup (which is unlikely because of the complexity of the system).

Centrifugal blowers are linear in power delivery because of how they work. They are basically belt driven turbochargers, which is why the Really quick drag racers use them. The belt allows them to build boost pressure quicker and not rely on exhaust gases to spin them (to build boost). The downside is parasitic loss and the pressure on the crank snout.

Once again, compromises.

Go give those videos by Richard I linked a watch when you have some time.
It is about efficiency.
It seems that because the turbo can create the same boost more efficiently you reach the same HP level with less boost on the turbo than with the SC--or the other way to interpret the result is that at the same boost level the turbo setup will be making a higher net HP.
If it takes 24lbs of boost to reach 1000hp with a SC, but the turbo can reach 1000HP with only 20lbs of boost, that's a lot less stress isn't it? (Plus you've got more room to go--once the turbo reaches 24lbs now you're well above 1000HP at what was the same stress level that only got you 1000HP with the SC).
I agree with you about it being about efficiency but it might also be that you need to make more power with the blower because of how much it's using up to spin it.

As Cheapokitty said, Boost is a measurement of restriction and it's ALWAYS more beneficial to make the same power on the least amount of boost possible. That's a sign of the efficiency that you are talking about. Not too mention, it's quite a bit easier on parts too.

Once again Cheapokitty, I Apologize for the hi-jack and will do my best not to let it happen again!
 

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I agree with number 1 but disagree with number 2. A PD (Positive Displacement) or TS (Twin Screw) blower isn't linear in power and will usually beat a PROPERLY sized turbo in the bottom end power department. You can undersize a turbo to pick up on the bottom but you'll overboost on top unless you have a sequential boost setup (which is unlikely because of the complexity of the system).
I didn't say linear in power I said linear in boost, as was demonstrated clearly by Richard's dyno test results.
 

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I'm Sorry but could you Please explain what you mean by linear in boost? I'll go back and watch his video too.

Thanks in advance! (y)
boost curves:
resulting power curves:

The boost vs RPM graph is very linear for all three SC types. The roots and twin-screw produce much more boost at lower RPM but are fairly linear with RPM as they increase. The centrifugal starts at almost no boost and rises almost perfectly linearly up to peak boost at max RPM. Meanwhile the turbo boost curve is vastly different, starting with very low boost at low RPM, hitting a steep rise in boost at a medium RPM range, then again going into a linear rise similar to the twin-screw and roots at the higher RPM ranges (or until clipped by by relief valve setting).

Trade offs abound--the roots has the highest low-rpm boost, but for some reason loses efficiency and drops off in the higher RPM range, while all the others look like they could just keep climbing.

The turbo produces more HP than the centrifugal at all RPM, and stomps on the other SCs above 3700 RPM in this test.
 

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@Cheapokitty if that's the plan for your service, one stop shop, then I'd say go for it. I'm assuming up front capital wouldn't be too risky since you're putting together the deal and coordinating for the customer. Win win to me. Get a few on the street, build a reputation for delivering and you'll be all set.

The parasitic drag from a supercharger vs the practically free HP from turbos makes sense. Where my head was going is if the rods get unhappy at say 1000hp are they less unhappy if that 1000hp comes form a turbo system vs a supercharger but maybe I'm over thinking it. There's no arguing a turbo system is more efficient. Sorry if I managed to derail your thread and good luck with your endeavor.
 

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Are you planning on working on these cars? I always thought a shop did all your installs. And you stated you don’t tune. Are you looking to just put a package together?
 

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Discussion Starter · #52 ·
I agree 100% that about your reputation comment but reputation's can also be repaired. I can prove this by using John Hennessey as my example. He BURNED the Corvette and Viper crowd to the ground and now has come back to build some high dollar modded cars that perform well and seems to have a thriving business.

My best suggestion pretty much parrot's what you (Blkout) said and treat people right the first time around because Folk's are trusting you with (what I consider) a large amount of money and just because you made one fast car, doesn't mean that you can consistently do it again. You have to prove that and the first couple of builds are paramount for you to get your rep established.

In all Honesty, I wouldn't automatically trust you because you've got many followers on Youtube. They mean nothing to me because I don't know them and I don't know you! Trust needs to be earned over time and results. You treat people right and they usually respond in kind!

Sorry to be a buzzkill too but I'm skeptical by nature and it's just how I think! :)

PEACE!



In actuality, turbo's are the restriction. They just eliminate parasitic drag over a blower. A turbo will slow down the exhaust speed until it comes out of the compressor side of the turbo, then it's not a restriction anymore. It's kind of like the old Hotwheel's Supercharger that you put on the track when playing with your Hotwheel's cars. The car is slowing down as it comes between the wheels and then the spinning wheels of the supercharger grab the sides of the car and "Boost" it out of the other side.

The exhaust is the car coming in and the "Boost" is it coming out.





The downside to downforce is that it creates drag to and can slow a car down. Everything has a compromise and things depend on what you're trying to accomplish. If it were a road course, then downforce is beneficial. On a drag strip, not so much because it's more about weight transfer than aerodynamics. Granted, a slipperier COD (Coefficient of Drag) will help on top, but that's not downforce.



No belts and/or crank pulley hanging off of the front of an engine. Crank snout isn't subjected to a belted pulley trying to spin off of the front of it. For some reason, turbo's seem to be easier on engine parts just because of how the boost is delivered. It's less violent but more efficient. If that makes any sense (it does in my little peanut head but sometimes I lose things in translation:( )



I agree with number 1 but disagree with number 2. A PD (Positive Displacement) or TS (Twin Screw) blower isn't linear in power and will usually beat a PROPERLY sized turbo in the bottom end power department. You can undersize a turbo to pick up on the bottom but you'll overboost on top unless you have a sequential boost setup (which is unlikely because of the complexity of the system).

Centrifugal blowers are linear in power delivery because of how they work. They are basically belt driven turbochargers, which is why the Really quick drag racers use them. The belt allows them to build boost pressure quicker and not rely on exhaust gases to spin them (to build boost). The downside is parasitic loss and the pressure on the crank snout.

Once again, compromises.



I agree with you about it being about efficiency but it might also be that you need to make more power with the blower because of how much it's using up to spin it.

As Cheapokitty said, Boost is a measurement of restriction and it's ALWAYS more beneficial to make the same power on the least amount of boost possible. That's a sign of the efficiency that you are talking about. Not too mention, it's quite a bit easier on parts too.

Once again Cheapokitty, I Apologize for the hi-jack and will do my best not to let it happen again!
All good Freddy and great feedback. I agree trust is earned, should I move forward the first couple cars will become my teammates, going around the country to different events and showing what's possible with turbo kitty's on stock PCM.
 

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Discussion Starter · #53 ·
@Cheapokitty if that's the plan for your service, one stop shop, then I'd say go for it. I'm assuming up front capital wouldn't be too risky since you're putting together the deal and coordinating for the customer. Win win to me. Get a few on the street, build a reputation for delivering and you'll be all set.

The parasitic drag from a supercharger vs the practically free HP from turbos makes sense. Where my head was going is if the rods get unhappy at say 1000hp are they less unhappy if that 1000hp comes form a turbo system vs a supercharger but maybe I'm over thinking it. There's no arguing a turbo system is more efficient. Sorry if I managed to derail your thread and good luck with your endeavor.
Thank you Speedy, I fully understand your over thinking, I hope my reply helped give you some clarity. Less pressure and heat in the combustion chamber keeps everything happy. The end horsepower number is only a measurement of energy efficiency.

As far as upfront costs it's pretty hefty with shop build out, staff, reproducing my kit at scale and tooling. However the R&D was already funded and done by me over the last couple years. Also marketing to my potential consumer base is virtually free if I leverage my strong YouTube and social media following.
 

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Discussion Starter · #54 ·
Are you planning on working on these cars? I always thought a shop did all your installs. And you stated you don’t tune. Are you looking to just put a package together?
Yup my friend and good buddy at Intrack provided me the opportunity to build this car with his staff at my direction. I would be expanding on this and building out a shop specifically to do these builds. It would be home and basis of all operations to take stock hellcats and turn them into 1100whp / 1300whp / 1500+whp monsters.
 

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Yup my friend and good buddy at Intrack provided me the opportunity to build this car with his staff at my direction. I would be expanding on this and building out a shop specifically to do these builds. It would be home and basis of all operations to take stock hellcats and turn them into 1100whp / 1300whp / 1500+whp monsters.
Are you good at wrenching or are you going to need to hire some high level staff?
going on this venture is going to take someone with some pretty good mechanical skills. Especially building your own kit.
 

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boost curves:
resulting power curves:

The boost vs RPM graph is very linear for all three SC types. The roots and twin-screw produce much more boost at lower RPM but are fairly linear with RPM as they increase. The centrifugal starts at almost no boost and rises almost perfectly linearly up to peak boost at max RPM. Meanwhile the turbo boost curve is vastly different, starting with very low boost at low RPM, hitting a steep rise in boost at a medium RPM range, then again going into a linear rise similar to the twin-screw and roots at the higher RPM ranges (or until clipped by by relief valve setting).

Trade offs abound--the roots has the highest low-rpm boost, but for some reason loses efficiency and drops off in the higher RPM range, while all the others look like they could just keep climbing.

The turbo produces more HP than the centrifugal at all RPM, and stomps on the other SCs above 3700 RPM in this test.
Thank You! That was interesting and educational too! (y)
 

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As far as upfront costs it's pretty hefty with shop build out, staff, reproducing my kit at scale and tooling. However the R&D was already funded and done by me over the last couple years. Also marketing to my potential consumer base is virtually free if I leverage my strong YouTube and social media following.
Hmmm. I thought you were using an existing group of folks with their own brick and mortar locations and you'd coordinate the build through them for the customer.

Do you have an option to run the first year or so as the build coordinator using existing shop/tuner as a litmus test for interest to limit up front capital outlay? That may be a safer route and let profits from the first year or so fund your own brick and mortar facility.
 

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On a drag strip, not so much because it's more about weight transfer than aerodynamics.
Especially on launch.
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Weight transfer is definitely paramount more and more as your weight goes up and your horsepower (relative to weight) goes down, thus making great weight transfer on launch to be increasingly important and down-the-strip traction not being at risk of being lost because the amount of weight over the rear axle is usually enough without any help from whatever aerodynamics are available at street car strip speeds.
 

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Lol you guys took my question down a rabbit hole but the question still stands. How is 1000hp from turbos or a supercharger any less load on the internal engine components?
I can guess what you were trying to point out: 1000hp out the crank puts a similar stress on the engine's guts no matter HOW that 1000hp was produced.

The answer is that the amount of GROSS horsepower that is required by an engine to end up with 1000hp exiting via the crankshaft is greater in supercharged engines than it is in turbocharged engines.

Top Fuel Dragsters, as an example, burn 800hp (it may be more nowadays) just turning their blower, so the TFD engine is making, for example, 10,800 hp and 10,000 is escaping via the crank.

Centrifugal superchargers have taken over Pro Modified, so it is likely they produce more NET power output in a drag-racing-friendly format (no boost lag like turbos may have) than would, for example "sits on top of the engine" blowers like PD blowers or screw blowers.

A turbo motor, once it gets spooled, does provide a bit of backpressure on the exhaust side, which is largely overbalanced by the boost pressure on the intake side, and thus, turbo motors have to make less GROSS power to achieve the same NET power, which is why they are used in big rigs, not the screaming Jimmy 8V92's of yore with their giant 8-92 superchargers forcing the two-stroke monsters to gobble as much air as they could.

The motor that has to have its internals subject to the forces required to produce 1200hp to net 1000hp will thus put more stress on its guts than an engine that only needs to make 1080hp to produce a net of 1000, assuming the parasitic effect of increased backpressure on a turbocharged engine can even be quantified a 80hp, but that would take a LOT more research than most are willing to quantify.

Now, the extra 120hp may not sound like much, but if you already kind of close to the edge of what any given component, like ring lands, may tolerate, that 120hp extra to produce the same net result can be a death sentence.
 

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boost curves:
resulting power curves:
I’m not refuting the results here and I know it’s not your video but do you happen to know how much of an impact that intercooler setup made? It seems noteworthy that the turbo had mention of an intercooler unless the supercharger setups already had an intercooler that the turbo setup couldn’t use?
 
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