dusterdoug
Well-Known Member
Soooo, quick background: Assembled a budget 416 a few years ago, and managed to run a best lap of 10.14 @ 128, irritate a few big block guys and won a few rounds including a Mopar race at Sac. Developed a bearing issue, so after we took it down to inspect and repair the car owner decided "enough". Having a low 10 second Duster was fun, but he wanted to convert the car to a 12.0 Sportsman car (no jacket, no dated belts, no fear of a mandatory engine diaper) AND be streetable. So we made changes, and I assembled a new motor.
Back to the 3.31 stroke crank
New SCAT rods
Sealed Power hyper flat tops (calculated CR is 10.3:1)
Comp Cam Hydraulic cam, .545/.545 - 241/247 @ .050" (XE285HL)
Same RHS heads from the 416, fresh with new Beehive springs.
FAST EFI 2.0
Same 904 from the 416, had the 8" converter tightened as much as possible, but still a touch too loose for the street...Need to work on that over the winter; we'll change it to a Lupo 9.5" that's on the shelf.
Swapped out the 4.56/spool for a 3.91 and Sure Grip
Tossed the many runs old Phoenix slicks on. Hmmm, 3.91's and 29.5 tire? Isn't that the same as a 3.55/27" gear/tire combo??? We want this thing to go 12.0's not 13.0's...LOL!
In addition, the car is now 170 lbs heavier: Stereo, FULL 3" exhaust to the rear, and power windows...
A tank full of 91 octane and some octane booster and off we go to the track.
Three runs made. Never touched anything except for some Cal Track adjustments and ran a best of 11.77 @ 114. Wow...love those 340's! Footnotes:
30* total timing.
Shifting at 5000 RPM. Yes, 5,000...it is a street car after all!
Across the stripe at (go back and re-read the gear/tire height) 5,200.
Maybe next time out, we'll get "serious" and run it to 6,000 and put some more timing in it. Oh and maybe play with the tune up?? We left the EFI on the base settings...didn't touch it. But how cool...change "jets" with the touch screen with the hood closed!
Should be a truly low maintenance, fun street/strip car!
Back to the 3.31 stroke crank
New SCAT rods
Sealed Power hyper flat tops (calculated CR is 10.3:1)
Comp Cam Hydraulic cam, .545/.545 - 241/247 @ .050" (XE285HL)
Same RHS heads from the 416, fresh with new Beehive springs.
FAST EFI 2.0
Same 904 from the 416, had the 8" converter tightened as much as possible, but still a touch too loose for the street...Need to work on that over the winter; we'll change it to a Lupo 9.5" that's on the shelf.
Swapped out the 4.56/spool for a 3.91 and Sure Grip
Tossed the many runs old Phoenix slicks on. Hmmm, 3.91's and 29.5 tire? Isn't that the same as a 3.55/27" gear/tire combo??? We want this thing to go 12.0's not 13.0's...LOL!
In addition, the car is now 170 lbs heavier: Stereo, FULL 3" exhaust to the rear, and power windows...
A tank full of 91 octane and some octane booster and off we go to the track.
Three runs made. Never touched anything except for some Cal Track adjustments and ran a best of 11.77 @ 114. Wow...love those 340's! Footnotes:
30* total timing.
Shifting at 5000 RPM. Yes, 5,000...it is a street car after all!
Across the stripe at (go back and re-read the gear/tire height) 5,200.
Maybe next time out, we'll get "serious" and run it to 6,000 and put some more timing in it. Oh and maybe play with the tune up?? We left the EFI on the base settings...didn't touch it. But how cool...change "jets" with the touch screen with the hood closed!
Should be a truly low maintenance, fun street/strip car!
