Small Block Stroker ... Gas mileage?

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Without overdrive and a tighter centerline camshaft, forget it..I've had my stroker since 2003 with 2.94s and many combos. Gets 14 hwy with a 1:1 fourth gear in an 833. BTW who drives 55? You'd get killed here driving like that...
 
GMachineDartGT said:
Without overdrive and a tighter centerline camshaft, forget it..I've had my stroker since 2003 with 2.94s and many combos. Gets 14 hwy with a 1:1 fourth gear in an 833. BTW who drives 55? You'd get killed here driving like that...
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I agree. Overdrive and cam tweaking (custom).

Read here about a 408 with high MPG: http://board.moparts.org/ubbthreads...estionAnswer&Number=4560573&fpart=&PHPSESSID= His cam duration @.050 is 216.

Plus be careful about listening to peoples claimed MPG. A lot of people figure it by just looking at the gas gauge between fill ups. Rather than really calculating the gallon difference between fill ups. And inconsistant fill up procedure with topping off can vary your results too. These older cars seem tempermental with the gas pump automatic shut off devices.


:burnout:

Also agree with GMachingDartGT on traffic. It's 70-80 mph here in the fastlane if traffic is open. That's about 3800-3900 rpm for me with 3.23 gears and 24.5" diameter tires. I've got 10.5 mpg out of my stroker. Going about 70-85 mph in sort of decent flowing traffic. Not totally steady like in the middle of Nebraska or anything.

416 stroker, comp 274S cam, 750 BG silver claw double pumper, M1 single plane, automatic trans.

My speedo in incorrect by about 7-8 mph.
 

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GMachineDartGT said:
Without overdrive and a tighter centerline camshaft, forget it..I've had my stroker since 2003 with 2.94s and many combos. Gets 14 hwy with a 1:1 fourth gear in an 833. BTW who drives 55? You'd get killed here driving like that...
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That's a nice combo and 14 is pretty darn good--I love to get that. The 3.91 gears cost me at the pumps. Strokers don't need as much gearing, 3.23 would be prefect for many towns and 2.94 for 75 mph zones.

Its rpm's and cam, tight centerlines get fewer mpg. The old 340 cam with 114 lbc got 15--16 mph in those cuda's with 3.55 gears. That cam is too small for any stroker engine. Carb tuning is a must.
 
Update: Since my last post in 2009, I have since switched to M/T ET Streets 295/55/17's, a Dynamic 9.5 inch converter 4000 stall, and a TQ rated at 850 cfm. On the highway @ 65 mph, around 3500 rpm, I consistently get 14 mpg through dana 60 3.73's. City is around 9. Best time of 12.003 @ 111, 408 stroker in 73 Duster, Edel RPM AL heads, 236/242 @ 0.050, .544 lift, 9.6:1 static. I can run 87 octane with no pinging, incidentally.

So with OD Gearing, maybe so!
 
jimmyray said:
Update: Since my last post in 2009, I have since switched to M/T ET Streets 295/55/17's, a Dynamic 9.5 inch converter 4000 stall, and a TQ rated at 850 cfm. On the highway @ 65 mph, around 3500 rpm, I consistently get 14 mpg through dana 60 3.73's. City is around 9. Best time of 12.003 @ 111, 408 stroker in 73 Duster, Edel RPM AL heads, 236/242 @ 0.050, .544 lift, 9.6:1 static. I can run 87 octane with no pinging, incidentally.

So with OD Gearing, maybe so!
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What intake and specifice cam part number are you running. And what headers?
 
autoxcuda said:
What intake and specific cam part number are you running. And what headers?
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Mopar M1 Single Plane
Hooker 1 5/8 comp headers
Comp Cams XR286HR-10 Hydraulic Roller

This is in a 1989 factory roller 360 truck block.

Incidentally, I think the ThermoQuad made the biggest difference. Super responsive bottom end, clean idle, great MPG, and actually cut 0.10 off the ET over the Holley 750DP.
 
jimmyray said:
Mopar M1 Single Plane
Hooker 1 5/8 comp headers
Comp Cams XR286HR-10 Hydraulic Roller

This is in a 1989 factory roller 360 truck block.

Incidentally, I think the ThermoQuad made the biggest difference. Super responsive bottom end, clean idle, great MPG, and actually cut 0.10 off the ET over the Holley 750DP.
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Was it a DemonSizzler built Thermoquad??
 
I get about 6-10 with my stroker. Then again, I'm running a low-geared transmission and 4.10's and have a 950HP sitting on top. With the right combo, you might be able to get the mileage you want.....if you can resist the urge and keep your foot out of it.
 
DusterKrazy said:
Was it a DemonSizzler built Thermoquad??
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It was. I bought an wide-band air/fuel gage and have tuned the carb to about 14.7 at idle, and cruise, and about 12 at WOT. That gage was the best $200 I've spent on the car. You can learn a lot about the goings on in the engine with that tool.
 
jimmyray said:
It was. I bought an wide-band air/fuel gage and have tuned the carb to about 14.7 at idle, and cruise, and about 12 at WOT. That gage was the best $200 I've spent on the car. You can learn a lot about the goings on in the engine with that tool.
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So what adjustment did you make to the Demonsizzler carb after you hooked of the air/fuel gauge? Rods, jets, air door, squirter, etc???
 
autoxcuda said:
So what adjustment did you make to the Demonsizzler carb after you hooked of the air/fuel gauge? Rods, jets, air door, squirter, etc???
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Rod's and jets, as well as the secondary door opening.
 
Current settings:
Carter TQ9024S, off a 440, 1.5" primaries

Primary jets = 100
Secondary jets = 159
TQ Air Bleeds = 0.088 (added by Demonsizzler)
Rods = 2109
Accel. Nozzle = 32
TQ Air Door = 12 mm from air horn
Air door spring = 1.5 turns
 
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