PSDPlayer vs IMELMO Deathmatch Procharger Shootout

Make it shaft drive and run it off the front driveshaft:hehe:

We need LOTS of video if this thing ever makes it into a truck. It may suck and it may fly, but we need video either way!:rockwoot:
 
PSDPlayer said:
With tube runners of different lengths (remember the tuned port corvette intakes)
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i dont know if you want to go that route, the TPI setup on the 305s and 350s is very restrictive, to small of a plenum and to long of runners atleast for an NA motor anyway. they made good torque but little HP, but the newer LT1s and Lsx motors use a totally different style intake manifolds and still make great torque with a lot more power up top. im gonna say that as far as runner length goes in our application i dont think lengthing them is going to help us any, but im interested to see your results. comparing NA gas manifolds to a forced induction diesel is apples to oranges but we'll see. however i think you may find alot more interesting results playing with plenum sizes. as im sure u know the plenum is like a holding tank for each cylinder to draw from, if it doesnt have enough volume the cylinder wont be able to take its fair share of air, i used to do lots of research and stuff on this back when i had a 305TPI camaro and a lot of us wanted to make the TPI shine on the top end. i still dont think the physics behind designing an NA manifold for a gasoline engine is going to apply to a forced induction diesel.
 
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Vizsla said:
I think that the members on here know turbo power is not free. If you think a supercharger is close to a turbo as far as parasitic losses are concerned, then you sir are wrong. The oem's have traditionally favored superchargers, but there are alot of different turbo engines about to be on the market, simply for fuel economy due to the more efficient nature of a turbo(check out the upcoming Ford gassers). Just an example - quite a few twin turbo mustangs running 700-1000 hp, not too many twin or single supercharger stangs doing that eh? Back to diesels, it costs almost no hp to spin a turbo and the idea of combining the two is a good one because the pitfalls of each are somewhat opposite meaning they should complement each other. IMO some engines will like it, some won't, just a cheaper easier way to get close to twin turbo performance. BTW it is not a new idea, remember the 2-stroke diesels with roots style blower and a turbo?
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Eh... I don't know about that. A centrifugal compressor (variable displacement) always has more slip, ie, loss, than a positive displacement compressor. Some applications it isn't that big a difference, or big deal. The move to turbos vs blowers I would be willing to bet is based on two things... cost and space. In that arena, the turbo wins hands down.

The other thing to remember also, is no OEM that I'm aware of ever used a centrifugal blower, they have all been roots or lysolm screw type. Large scale commercial air compressors also run screw compressors to move large amounts of air and volume because of their efficiency.

What would really put this to bed is a strain gauge on the shaft of the turbo... Then we'd know exactly how much power the turbine is generating "for free". I'll bet it's within 5% of the power required by a blower that produces the same pressure and volume.

Until that happens, this probably isn't a discussion worth having.
 
Kleetus said:
What would really put this to bed is a strain gauge on the shaft of the turbo... Then we'd know exactly how much power the turbine is generating "for free". I'll bet it's within 5% of the power required by a blower that produces the same pressure and volume.

Until that happens, this probably isn't a discussion worth having.
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I'm going to disagree here...

I cut my teeth on the old small block ford stuff... a turbocharged setup on a 302 always made more RWHP at a given boost level than a centrifugal blower, and I can't tell you how many broken cranks we ended up with because of the side-loading from the belt.
 
Not talking about a paxton or vortech centrifugal only, I was never a particular fan of those noisy, poorly mounted things. IMHO, they are junk. The power requirements of one of those is an exponential curve, so yeah, you probably would break things with those. My cousin had a whipple charger on his 91 gt with 65-70k with the factory belt. Broke one belt at like 55k. he was 500+ hp, (basically at the limit of the stock computer, it would run like crap below 45 degrees or so)

Look under the hood of an E55... 6 rib serpentine belt, 550+ hp, with 5.4 liters., and a flat torque curve to red line. 50k warranty, and with a clutch no less...
 
Kleetus said:
Not talking about a paxton or vortech centrifugal only, I was never a particular fan of those noisy, poorly mounted things. IMHO, they are junk. The power requirements of one of those is an exponential curve, so yeah, you probably would break things with those. My cousin had a whipple charger on his 91 gt with 65-70k with the factory belt. Broke one belt at like 55k. he was 500+ hp, (basically at the limit of the stock computer, it would run like crap below 45 degrees or so)

Look under the hood of an E55... 6 rib serpentine belt, 550+ hp, with 5.4 liters., and a flat torque curve to red line. 50k warranty, and with a clutch no less...
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roger that, I thought we were still talking centrifugals... the screw blowers rob power too though. I'm willing to bet that he would have seen another 25-50hp at the same boost level. Obviously the whipple has instantaneous boost.

the only reason I see to run a centrifugal is ease of bolt-on vs. a turbo for most people or if you're sponsored or if you're in a small tire class that's going to have you pedaling vs. falling under a big charger
 
The move to turbos vs blowers I would be willing to bet is based on two things... cost and space. In that arena, the turbo wins hands down.

Straight from FOMOCO - We are employing turbocharging due to the ability to signifigantly increase fuel economy and achieve 8 cyl performance from 6 cyl's, and 6cyl performance from 4 cyl's. Just thought I'd bring their marketing strategy to light. Don't disagree with you, but I have personally seen a mustang with a blower perform better when switching to a turbo setup. I still stand behind turbos being more efficient than superchargers, but it's not like it is a big difference, just a little advantage. Some hard data would be nice and I agree that untill then this is a dead issue.
 
it's a big difference... you can mount a turbo anywhere, you make use of wasted exhaust energy, no side-loading the crank, non-linear boost curve (turbo smacks way harder than a centrifugal blower), etc.
 
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