71Demon540
Well-Known Member
I know it’s not an A-body, but it’s the car that got me into this mess of being a racing addict. 1968 Plymouth Hemi Roadrunner, RM23J vin, original 426 hemi, 4 speed, Dana hardtop car. My dad owned it since 1980 after buying it from a close friend who needed the money after the Vietnam war. Car was raced for years with the original iron block and iron heads. Then finally got a 540 bullet built for it few years back. After some smashed oil pans, and losing oil at the big end on two separate occasions, one of which my dad spun into the other lane and almost crashed into his opponent, the engine failed after that. That was 2021. Since then, we go a new KB block, with molnar crank, Oliver rods, and new diamond pistons, along with other rebuild components.
Now we turned it up to a 572 with 14.4:1 compression, Stage V replacement cylinder head (no change), Ray Barton rocker arms (no change), new molnar crank, Oliver rods, custom diamond pistons, same bullet cam, same Ray Barton single plane intake, new APD 1250 billet dominator, new TTI headers 2 1/4x4” with some cool kickout collectors, an all out racing 727 that was upgraded to hardened input shaft and output shaft, new strange 35 spline axles with 5/8” wheel studs replacing the old axles and 1/2” studs, new strange rear brakes replacing the wilwood rear brakes, and same turbo action 8” converter. Car weighs between 3365-3400 with driver, depending on the scales it is on and how much fuel is in it. Will get a more accurate weight this season. Ladder bar with floater rear suspension on a Calvert split mono leaf. 4.56 gears, Dana 60, 29.5/11.5w Hoosier stiff sidewall slick. Strange rear shocks, Viking front shocks. Stock torsion bar front end with stock upper and lower control arms (Which will be replaced this season god willing)
The engine went in back in end of March. Fired it up early April, and have been workin on it since to get it 100% race track ready. Well, finally, the weekend has come.
The 540 ran a best of 9.15 at 144.46mph, and a 5.80 at 118mph in the 1/8. That was with 4.88 gears, super stock springs, had a tiny vac leak so vac pump was not doing squat, an old holley 8896-2 1050 dominator from the iron engine, and old hooker 2 1/8x4” collector again from the iron engine. We were quite pleased with the 540’s performance especially knowing we had changes to be made that never got made because of the failure we eventually met.
Knock on wood weather this weekend at our local track seems to be going in the right direction, so hopefully we will get some good laps on the car without fighting too hard. Just want it to hook, go straight, go fast, be safe, and controllable.
Now we turned it up to a 572 with 14.4:1 compression, Stage V replacement cylinder head (no change), Ray Barton rocker arms (no change), new molnar crank, Oliver rods, custom diamond pistons, same bullet cam, same Ray Barton single plane intake, new APD 1250 billet dominator, new TTI headers 2 1/4x4” with some cool kickout collectors, an all out racing 727 that was upgraded to hardened input shaft and output shaft, new strange 35 spline axles with 5/8” wheel studs replacing the old axles and 1/2” studs, new strange rear brakes replacing the wilwood rear brakes, and same turbo action 8” converter. Car weighs between 3365-3400 with driver, depending on the scales it is on and how much fuel is in it. Will get a more accurate weight this season. Ladder bar with floater rear suspension on a Calvert split mono leaf. 4.56 gears, Dana 60, 29.5/11.5w Hoosier stiff sidewall slick. Strange rear shocks, Viking front shocks. Stock torsion bar front end with stock upper and lower control arms (Which will be replaced this season god willing)
The engine went in back in end of March. Fired it up early April, and have been workin on it since to get it 100% race track ready. Well, finally, the weekend has come.
The 540 ran a best of 9.15 at 144.46mph, and a 5.80 at 118mph in the 1/8. That was with 4.88 gears, super stock springs, had a tiny vac leak so vac pump was not doing squat, an old holley 8896-2 1050 dominator from the iron engine, and old hooker 2 1/8x4” collector again from the iron engine. We were quite pleased with the 540’s performance especially knowing we had changes to be made that never got made because of the failure we eventually met.
Knock on wood weather this weekend at our local track seems to be going in the right direction, so hopefully we will get some good laps on the car without fighting too hard. Just want it to hook, go straight, go fast, be safe, and controllable.
