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LHevent.com
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Discussion Starter · #1 · (Edited)
496 MAGNUM HO BBC WHIPPLE SUPERCHARGED vs. 355ci Supercharged SBC Fuel Efficiency/HP

VS.

496ci MAGNUM HO (425hp) EFI WHIPPLE SUPERCHARGED 92-Octane Fuel
Dyno Results
RPM-3593 Trq-713.9 HP-488.4 PSI-5.4 BSFC-0.555
RPM-5371 Trq-642.6 HP-657.1 PSI-6.2 BSFC-0.622
DATA

355ci SBC (435.7hp) TBS671-Supercharger 750 E-85 (104-octane) Demon Carbs
Dyno Results
RPM-4500 Trq-778.7 HP-667.2 PSI-12.0 BSFC-0.490
RPM-5500 Trq-754.8 HP-790.4 PSI-12.0 BSFC-0.530
DATA

Winner
355 SBC​

Winning Results
141-ci less!
133-hp more!
65-Trq more!
0.092 BSFC more fuel efficient!​

Brake specific fuel consumption (BSFC) is a measure of how many pounds of fuel it takes to make 1 hp for 1 hour (lb/hp-hr). A 0.5 BSFC number is considered the norm for an average, normally aspirated, carbureted engine. The lower the BSFC number, the greater the engine's efficiency well-tuned race engines get down in the "low 4s." On the other hand, supercharged and nitrous engines usually are run rich to play it safe, so it's not unusual to see high 5s" or "low 6s" in these applications.​

14.7Psi's = Double the engine HP.
or
6.803% HP gain per psi​


I'm no expert by far so I delt with:​


According to Boost Daddy, SBC are more efficient at HP vs. BBC when supercharged. When I spoke tho THE BLOWER SHOP, they highly
recommended this guy. The dude is very cool & is open to talk tech.

I agree 92octane vs 104octane & 6lbs of boost vs 12lbs of boost makes a difference, but consider:​

92octane @ $2.75
vs
104octane E85 @ $2.20.​

& the fuel requirement to make a certine level of HP & Tourqe (0.092 BSFC more fuel efficient) it should raise a brow. Also there is a weight factor benifit.​

I agree theirs no replacement for displacement, this comparison should raise the other brow.​
 

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RPM-5371 Trq-642.6 HP-657.1 PSI-6.2 BSFC-0.622

RPM-5500 Trq-754.8 HP-790.4 PSI-12.0 BSFC-0.530:)Unsure
 

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VS.


496 MAGNUM HO EFI WHIPPLE SUPERCHARGED 92Octane Fuel
RPM-3593 Trq-713.9 HP-488.4 PSI-5.4 BSFC-0.555
RPM-5371 Trq-642.6 HP-657.1 PSI-6.2 BSFC-0.622
DATA

355ci SBC TBS671-Supercharger 750 E-85 Fuel Demon Carbs
RPM-4500 Trq-778.7 HP-667.2 PSI-12.0 BSFC-0.490
RPM-5500 Trq-754.8 HP-790.4 PSI-12.0 BSFC-0.530
DATA

Winner
355 SBC​

Winning Results
141-ci less!
133-hp more!
65-Trq more!
0.056 BSFC more fuel efficient!​


Brake specific fuel consumption (BSFC) is a measure of how many pounds of fuel it takes to make 1 hp for 1 hour (lb/hp-hr). A 0.5 BSFC number is considered the norm for an average, normally aspirated, carbureted engine. The lower the BSFC number, the greater the engine's efficiency well-tuned race engines get down in the "low 4s." On the other hand, supercharged and nitrous engines usually are run rich to play it safe, so it's not unusual to see high 5s" or "low 6s" in these applications.​
Not mine, 655hp @ 5500rpm 722lb @ 4000rpm 7psi of instant boost. It fits under the hood with no modifications, and idles like a caddy. Cruises at 70mph at @4000rpm in vaccume not boost. I guess it depends if you want a race motor or a sleeper that runs its ass off.
 

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LHevent.com
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17 Posts
Discussion Starter · #7 ·
So I am confused, are you selling these engines?
TNTDUNER,

No TOM @ Pro marine can build one with even more reliable HP. I think his No is (928) 505-DYNO. He's really good people.

I just wanted to show off my motor that Im going to run on a 26cat. I think it's an option mfg's should consider due to EPA/CARB 2010. It could offer more performance at a cheaper cost to operate and (Not to sound like a tree hugger) better for the environment.

The engine cost me?
$1500 from GM
$1500 for Pro 1 head & Inconel Valves & Springs
$500 minor port work
$2000 4340 Crank Rods JE pistons & rings
$4800 Suercharger & Cooler kit
$1000 cam & roller system
$300 Oil Pan
$1000 for carbs
$1500 EMI headers
$500 Cam Belt pulley system
$2000 on extras
$16,600.00 or so.
 

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Havasu & Anaheim Hills
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361 Posts
I spoke with Tom the other day about building a 540 big block with about the same hp (no blower), I wonder what he would charge to build something similar?
 

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LHevent.com
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17 Posts
Discussion Starter · #10 ·
You know, I think Tom at Pro Marine has some 540BBC ready to go. When Tom dyno'd my motor I asked him about E-85 on BBC. I think He said for BBC, non supercharged, Nat/Asp he got worse results on E85 than on pump gas.

He & I already know it works very well on motors like mine but I don't know if he has had a chance to try the same application on a Shupercharged BBC.

I just tried calling him, but his staff said he's on the lake testing a motor & probably running about 130mph on glass right about now.:D
 

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LHevent.com
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17 Posts
Discussion Starter · #11 ·
How about taking that system and bolting it on an LS series small block, the old small block platform is a dinosaur !

I think the LS block displacement is the same & the LS is aluminum vs. iron. The LS heads & Induction are different. The fuel management system upgrade for EFI is something you world have to consider too. My set up is boost referanced & is smooth at idel. I guess you could run carbs but then at that point, why run an LS block?
The weight factor is something to take advantage of though.

Am I right to say, Boats like to be light for speed.

This guy took the same budget 22 SVS Sting Ray boat I have with a 434 Nat/Asp motor & runs 100mph all day for 3 years on the same motor! He said it's due to being light.

RLC PERFORMANCE ENGINEERING

 

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LHevent.com
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17 Posts
Discussion Starter · #12 ·
Not mine, 655hp @ 5500rpm 722lb @ 4000rpm 7psi of instant boost. It fits under the hood with no modifications, and idles like a caddy. Cruises at 70mph at @4000rpm in vaccume not boost. I guess it depends if you want a race motor or a sleeper that runs its ass off.

Torque monster at 4000rpm & 722trq!
Mine at 4000rpm is 764.5trq & 582.3hp & at 5500rpm my hp is 790.2.

My sbc fit under the hood too with a normal low profile air scoop that is.

You & I are in the range of the Mercery Racing HP700 SCi engine. I wounder how much torque this motor produces?

Any Idea how much this motor cost $$$?
 

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LHevent.com
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17 Posts
Discussion Starter · #13 · (Edited)
TNTDUNER,

I spoke to Tom @ Pro Marine in Havasu. He said he did use a supercharger on a 540 block w/E85.

He said it wouldn't get past 1000hp for some reason. He also stated that the fuel usage was 20% higher with E85 than pump gas but got way more power from E85 and it run cooler.

I said, "still 1000hp for a conservative BBC aint bad at all" I guess for Tom, he works alot with motors producing over 1000hp.

Tom also said he just sold the motors he had on hand but he builds motor anytime you need them & at a Hell of a Price!
 

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Distinguished Member
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412 Posts
Makes sense. E85 is similar in specific gravity to methanol. It takes more fuel but makes tons of power, and burns cool. Use a massive pump and double your tank size.
 
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