Who is BS'ing who?
Sixty five posts in this thread and we've heard about 318s, 340s, 360s, slantys, motorcycles, GMs and Lexus'. We've had all the experts chime in on how to get better gas mileage out of your ***. No one has chimed in on how they are getting such great gas mileage out of their strokers.
The original poster is calling out a couple of specific members who made pretty incredible claims on another thread. Now they are silent...
Thank you Brian you got the point perfectly. :prayer:
cuda67, I'll help you cut through the BS and get to the "factual" information. Here goes…
Agree. I did not build my 408 for mpg. But I did build it to be street driven, and driven distances (measured in hundreds of mile). The "rules" I set for my build were: great torque (torque is king on the street), good horsepower, and it had to look old school. For me old school meant that I was going to use an LD-340 (dual plane), mechanical fuel pump, stock appearing ignition (used FBO system) and my 1991 360 with 308 heads.
Okay cool, you like factual information, me too. So why don’t we turn your rant into some facts so others who are looking to build their motor have a basis in fact.
My proposal; I’ll outline my engine build and drivetrain specs, and you post your info right next to mine for comparison. Then we can let folks analyze the factual differences between our builds. I believe we both built fast street cars so this should be a good comparison.
For everyone else; If you compare your build to mine remember I did not build this car to be a “race only” car or motor. Yes, I know I could have gotten more horsepower/torque if I had only (you fill in blank). So go back and read my rules for my build. Let’s keep it in line with cuda67’s original premise that decent performance and livable mpg cannot co-exist.
Are you game? Here goes:
Car:
1972 Demon
4-speed (close ratio gear set)
Rear: 8.75 with 3:55 Sure Grip
Rear Tire: Nitto Drag Radial 275/50-15 (25.75 dia.)
Exhaust: TTI step header and full 2.5" with X-pipe
Speedo pinion: 35
Speedo calibrated by Redline Gauge Works
Highway mpg 15.46
This was a 500 mile trip averaging 60 MPH with normal driving (no drag racing). I stopped every 150-170 miles to top off the tank (because at that point I was down to 1/4 tank) and to give my tailbone a rest. The route was from the east coast of Virginia to Roanoke using two and four lane roads (Rte 5, Rte 106, and Rte 460).
Camshaft - Hydraulic Roller (Cam Motion)
Duration Intake @50 242
Duration Exhaust @50 248
Lift Intake: 570
Lift Exhaust: 562
Lobe Separation: 110
Centerline (Installed): 105.5
Valve Springs (Comp Cams: 994-16)
Rockers: Comp Cams Pro Magnum Roller Rocker Arms, 1.5 ratio
Roller Lifters, 1991 LA 360 Stock
Crankshaft, Cast (Eagle) Internally Balanced, Stroke 4.000”
Pistons (Wiseco, Pro Tru Forged) PN: WISPT036H3
Bore: 4.030
Dish: 20cc
Compression Height: 1.460
Compression Ratio (Based on head gasket that is .039 thick with a 4.180 bore and a piston deck height of .0040)
Static Compression Ratio: 9.84:1
Dynamic Compression Ratio: 8.85:1
Dynamic Cranking Pressure: 179.26 PSI
Heads casting #4448308
Combustion Chamber Volume: 65cc
2.02" Intake (CFM)
1.60" Exhaust (CFM)
Flow: (Intake/Exhaust)
0.100 Lift 64 50 78.12
0.200 Lift 132 98 74.24
0.300 Lift 184 136 73.91
0.400 Lift 226 175 77.43
0.500 Lift 254 189 74.41
0.600 Lift 247 196 79.35
Carburetor (Pro Systems Pro Series - XE)
Holley 4150 HP Main Body
Jets: 75/85
Power Valve: 6.5/plug
Accelerator Pump: 50 cc/30 cc
Vacuum @ 1000 RPM: 11"
Distributor: FBO Mopar Electronic Ignition A688
Initial Timing: 18 Degrees
Total Mechanical @ 3200 RPM 16 Degrees
Vacuum Advance (@ 10 inches) 12 Degrees
Timing set @: 34 Degrees
Engine Dyno results: (with el-cheapo 1-5/8 headers because TTIs wouldn’t fit on dyno)
Peak Torque @ 4100 RPM: 460
Peak horsepower @ 5800 RPM: 443
Here is my info. may not have all you need but I will give you what I have.
Car: 1967 Barracuda vert.
904 tranny with a shift kit and 3000 stall converter
8.75 rear 3:23 sure grip
rear tires Nexen radials 275/40ZR x 17 (don't have height}
Stock manifolds with Flowmaster exhausr 2inch
Speedo gear 36 teeth (not calibrated but checked accurate with gps.
Holley 4150 Street Avenger 770, primarie jets 72, secondary jets 75
6.5 power valve
11 inches of vacuum
*P5153475 360 Magnum Crate Engine — 390 Horsepower, 420 ft.-lbs. Torque Magnum Block Thermocycled .020" Overbore
Specifications:
• Thermocycled Block Is Bored to +0.020" Oversize
• New Magnum R/T Big Valve Cylinder Heads
• Mopar Cast Aluminum Valve Covers
• High-Strength Stainless Steel Valves — 2.02" Intake, 1.62" Exhaust
• Heavy-Duty Valve Springs
• Hydraulic Roller Camshaft — 288°/292° Advertised Duration
(230°/234° Duration @ .050") 0.501"/0.513" Lift
• Pistons — 9.0:1 C.R.
• Single Plane, M1® 4-bbl Aluminum Intake Manifold (Includes Bosses for MPI
Conversion; Taller than Stock — Check Hood Clearance)
• Double Roller Timing Chain and Sprockets
• Center Sump Oil Pan Similar to Commando Engine (Fits Passenger Cars;
Pan Swap Required for Truck Use)
• Mopar Performance Electronic Ignition Kit with Distributor
Hwy miles 9