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Fastest Poly cars?

polyjohn

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Hi B-bods,
I would like to return to track,(once it opens again) with a Poly engined B-bod.
What’s the fastest anyone knows of?
Seen some big Poly builds on Dyno’s but what’s happening in the real world...:mob:
 
Search the web for 'POLY' and 'Gary Pavlovich'. You will be amazed.
He's a GREAT guy too and loves to talk Polys.
 
Unless you like spending lots of money on obscure stuff to go slow, I really don't see the point in building a Poly. Sure, people have done magazine articles for build-ups that made 500 hp, but they were labor and money intensive with lots of one off stuff!
 
You could build a hemi out of used parts for what you'd spend on making a poly fast.
 
Unless you like spending lots of money on obscure stuff to go slow, I really don't see the point in building a Poly. Sure, people have done magazine articles for build-ups that made 500 hp, but they were labor and money intensive with lots of one off stuff!
If I had a dime for everyone who told me to yank out that boat anchor and drop in a 340. Sometimes you like just building something different. Agreed, no speed parts and lots of money to build. So what. Want to go fast? Build something else, OR build a 500 hp Poly. Ive heard all the negatives. I still prefer hearing someone ask, ‘what’s that’? Even some MOPAR people.
 
Guy I know took this 65 Dodge 4 door to 12.9's with a 150hp shot of nitrous.
terry's 65 oic 1.PNG
terry's 65 pic2.PNG
Terry's 65 pic3.jpg
 
A while back I had a conversation with a very learned friend about MOPAR engines and specifically POLYS. The following is what came from that conversation. Please know it is not meant to disparage or denigrate any other brand or engine design - I've built many Chevys in the past - or anyone's choice of what to build. I just found these facts interesting.
  • THE A POLY AND LA 273/318/340 & 360 MOPAR IS SUPERIOR IN METALLURGY & STRENGTH AND HAS A SUPERIOR ROD STROKE RATIO DUE TO LONGER ROD LENGTH OF 6.123". THIS LONGER ROD YIELDS A SUPERIOR "ROD/STROKE RATIO" OF 1.85 to 1 & 1.71 to 1 vs. A CHEVY 350 of 1.64 to 1.
  • MOPAR HEADS HAVE SUPERIOR COMBUSTION CHAMBERS (ESPECIALLY THE POLYSHERICAL 318 HEADS ) WITH IMPROVED VALVE ANGLE FOR LARGER VALVES & GREATER BMEP (Brake Mean Effective Pressure), HIGHER PORT VELOCITY & IMPROVED FLAME FRONT/HEAT PROPAGATION.
  • 318 POLYSHERICAL HEAD DESIGN INCORPORATES A RIGID SHAFT MOUNTED ADJUSTABLE ROCKER ASSEMBLY THAT SURPASSES THE 340/360 FACTORY DESIGN.
  • ONLY DEDICATED RACE ENGINES OR EXPENSIVE AFTERMARKET EQUIPMENT MODIFICATIONS EMPLOY AS STOUT A ROCKER ASSEMBLY.
  • MOPARS HAVE SUPERIOR /THICKER BLOCK DESIGN FOR MORE RIGIDITY AND THE GREATEST NICKEL CONTENT FOR INCREASED STRENGTH & LONGEVITY AND RESULTS IN VASTLY THICKER CYLINDER WALLS FOR SUPERIOR MAJOR & MINOR THRUST WALL THICKNESSES (Less movement for more power/power potential/longevity), AND LARGER/STRONGER MAIN CAPS AND BOLTS SO ONLY 2 BOLTS MAIN CAPS ARE SUFFICIENT FOR HUGE POWER (ie 318 Poly, 340, 360) vs. Chevy THAT REQUIRES 4-BOLT MAINS FOR AN HP ENGINE.
  • SUPERIOR MOPAR CAMSHAFT PROFILES THAT INCORPORATE MORE DURATION & LIFT @ .050" LIFTER RISE AT ALL RPM LEVELS DUE TO THE LARGER .904" LIFTER BORE DIAMETER. Chevy & FORD ARE LIMITED TO .842" & 8.74" RESPECTIVELY. IF CHEVY TRIED TO USE A HIGHER PERFORMANCE MOPAR CAM DESIGNED TO TAKE ADVANTAGE OF THE .904" LIFTER BORE, THE CHEVY WOULD HANG A LOBE AND DESTROY THE CAM TUNNEL AND GRENADE THE ENGINE
  • SUPERIOR MOPAR FACTORY DUAL PLANE HIGH RISE INTAKE MANIFOLDS & GREATER CFM CARBURETORS ie 800CFM THERMOQUAD & 625CFM AVS CARBS vs. CHEVY ROCHESTER AND THEIR LOW-RISE INTAKE MANIFOLDS.
  • SUPERIOR MOPAR FORGED STEEL CRANKSHAFTS IN ALLPOLY 318 ENGINES & 1968-72 340'S AND SUPERIOR CAST CRANKSHAFTS vs. CHEVY SMALL BLOCKS.
  • 340'S ARE RARER AND MORE EXPENSIVE THAN THE UBIQUITOUS & INEXPENSIVE 360 WHICH WOULD BE THE MORE PRACTICAL APPROACH "IF" SWAPPING SMALL BLOCKS WAS THE INTENTION. HOWEVER THE POLY 318 IS MORE THAN CAPABLE OF ANNIHILATING A CHEVY 283, 327, OR 350 IN STOCK STROKE & AND IN FACTORY 2BBL. FORM THAN THE 2BBL. CHEVY...LET ALONE IN MOPAR STROKER MOTORS.
  • NOTE: THE HOT ROD MAGAZINE SMALL BLOCK & BIG BLOCK ENGINE CHALLENGES WHERE DICK LANDY BUILT MOPAR SMALL BLOCK & MOPAR BIG BLOCK BEAT ALL FORD & CHEVY BUILDERS ENTRIES BY A SIGNIFICANT HP & TORQUE MARGIN.
  • POLYS MADE FAR MORE HP & TORQUE THAN CHEVY SMALL BLOCKS FROM 1957-1966 ie 1966 283 CHEVY 195HP & 285TQ @ 2400 RPM VS. 1957-66 POLY 318 240HP & 340TQ @2400 RPM AND THE 4BBL POLY 318 MADE 260HP & 350TQ @2800RPM vs. 4BBL CHEVY 283 220HP & 295TQ @ 3200RPM...AND NOT TO MENTION THE 1957 DUAL QUAD FACTORY POLY AT A BLISTERING 290HP THAT FAR EXCEEDED ANY OTHER MGR'S POWER RATING AT THAT TIME AND YEARS THEREAFTER.
  • AND THE 1956 DAYTONA BEACH FLYING MILE RUN WHERE THE 1956 PLYMOUTH FURY 303 cid POLY RAN 148MPH TO ESTABLISH AN UNDEFEATED UNOFFICIAL SPEED RECORD.
  • NOTE: NO MODIFIED FACTORY ENGINE HAS MADE MORE BRUTE POWER THAN THE CHRYSLER/MOPAR FACTORY 1957 392cid HEMI & 1964 426 HEMI. THESE CHRYSLER DESIGNED PASSENGER CAR ENGINES HAVE BEEN USED FOR DECADES IN DRAGSTERS/RAILS/FUNNY CARS MAKING OVER 3000HP...A FEAT NO OTHER "CAR COMPANY" HAS ACHIEVED.
  • MOPARS ARE EXPENSIVE TO BUILD IS A GROSS EXAGGERATION AIMED TO INSULT YOUR INTELLIGENCE AND DISSUADE YOU FROM EXAMINING THE LONG ESTABLISHED FACTS OUTLINED ABOVE. SUCH FANTASY CLAIMS ATTEMPT TO POLARIZE TRUTH FROM FICTION, OBFUSCATE THE PROVEN COST EFFECTIVENESS & BUILD COST DATA WHEN A SIMPLE CATALOG PAGE SEARCH OR ONLINE COST COMPARISON/CONTRAST FROM SUMMIT RACING SHOWS AN AVERAGE OF ABOUT 1O% MORE TO BUILD THE MOPAR 318/340/360 VS. THE CHEVY SMALL BLOCK...ie SUMMIT RACING COST FOR MOPAR EAGLE 6.123 CONNECTING RODS $309 (and even less from other online vendors PERFORMANCE PARTS WHSE $279!) VS. CHEVY 6.125 RODS FOR EVEN MORE CASH @ $317!!! AND THEY ARE "OUT OF STOCK." AND SO IT GOES WITH A PART BY PART COMPARISON CONTRAST WHEN WE ITEMIZE EVERY INTERNAL ENGINE COMPONENT...BUT WHEN YOU REMEMBER THE SUPERIOR STRENGTH CHARACTERISTICS INHERENT IN THE MOPAR SMALL BLOCK DESIGN, CHEVY LOSES THE DURABILITY AND POTENTIAL POWER BATTLE AGAIN AND AGAIN.
  • NOTE: THE BIG BLOCK CHEVY 396 & AND FORD 351C REALIZED THE INHERENT DESIGN ADVANTAGE OF THE YEARS EARLIER MOPAR "CANTED VALVE" POLY ENGINE AND THUS INCORPORATED THIS SUPERIOR MOPAR DESIGN INTO THEIR 396 & 351 ENGINES, ALBEIT NOT COMPLETING THE FULL SUPERIORITY OF THE UNIQUE "POLYSPHERICAL" CHAMBER.
  • NEWER HEMI COMBUSTION CHAMBER DESIGNS ARE VERY SIMILAR TO THE ORIGINAL POLY DESIGN.
  • WHAT TO BUILD IS A SUBJECTIVE MATTER OF TASTE AND PERSONAL PREFERENCE WHILE THE AFOREMENTIONED "DATA/SPECS" ARE FACT AND NOT SUBJECTIVE. I LIKE CERTAIN MODELS OF ALL MAKES OF VEHICLES BUT I CANNOT DENY INHERENT ADVANTAGES & DISADVANTAGES OF ANY FACTORY VEHICLE/ENGINE & DRIVETRAIN DESIGN.
  • WHEN ATTEMPTS ARE MADE TO DISSUADE ME FROM BUILDING A POLY I NOTE THE UNIVERSAL MAXIM: "A MAN PERSUADED AGAINST HIS WILL IS OF THE SAME OPINION STILL."
 
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I dig different, that’s why I love my Mopars period. No influx of brand x parts either..Build the poly and keep us in the loop this sounds interesting, I’ve always thought it was the underdog engine that really was built well... Good luck!
 
Or you could do what I do and write "318 Poly" on your tech card at the dragstrip while running an RB stroker. Lots of head scratching when my 3,700 lbs. all steel, full interior street car runs a 10.0 @ 133 after announcing it's Poly powered. LOL
 
A while back I had a conversation with a very learned friend about MOPAR engines and specifically POLYS. The following is what came from that conversation. Please know it is not meant to disparage or denigrate any other brand or engine design - I've built many Chevys in the past - or anyone's choice of what to build. I just found these facts interesting.
  • THE A POLY AND LA 273/318/340 & 360 MOPAR IS SUPERIOR IN METALLURGY & STRENGTH AND HAS A SUPERIOR ROD STROKE RATIO DUE TO LONGER ROD LENGTH OF 6.123". THIS LONGER ROD YIELDS A SUPERIOR "ROD/STROKE RATIO" OF 1.85 to 1 & 1.71 to 1 vs. A CHEVY 350 of 1.64 to 1.
  • MOPAR HEADS HAVE SUPERIOR COMBUSTION CHAMBERS (ESPECIALLY THE POLYSHERICAL 318 HEADS ) WITH IMPROVED VALVE ANGLE FOR LARGER VALVES & GREATER BMEP (Brake Mean Effective Pressure), HIGHER PORT VELOCITY & IMPROVED FLAME FRONT/HEAT PROPAGATION.
  • 318 POLYSHERICAL HEAD DESIGN INCORPORATES A RIGID SHAFT MOUNTED ADJUSTABLE ROCKER ASSEMBLY THAT SURPASSES THE 340/360 FACTORY DESIGN.
  • ONLY DEDICATED RACE ENGINES OR EXPENSIVE AFTERMARKET EQUIPMENT MODIFICATIONS EMPLOY AS STOUT A ROCKER ASSEMBLY.
  • MOPARS HAVE SUPERIOR /THICKER BLOCK DESIGN FOR MORE RIGIDITY AND THE GREATEST NICKEL CONTENT FOR INCREASED STRENGTH & LONGEVITY AND RESULTS IN VASTLY THICKER CYLINDER WALLS FOR SUPERIOR MAJOR & MINOR THRUST WALL THICKNESSES (Less movement for more power/power potential/longevity), AND LARGER/STRONGER MAIN CAPS AND BOLTS SO ONLY 2 BOLTS MAIN CAPS ARE SUFFICIENT FOR HUGE POWER (ie 318 Poly, 340, 360) vs. Chevy THAT REQUIRES 4-BOLT MAINS FOR AN HP ENGINE.
  • SUPERIOR MOPAR CAMSHAFT PROFILES THAT INCORPORATE MORE DURATION & LIFT @ .050" LIFTER RISE AT ALL RPM LEVELS DUE TO THE LARGER .904" LIFTER BORE DIAMETER. Chevy & FORD ARE LIMITED TO .842" & 8.74" RESPECTIVELY. IF CHEVY TRIED TO USE A HIGHER PERFORMANCE MOPAR CAM DESIGNED TO TAKE ADVANTAGE OF THE .904" LIFTER BORE, THE CHEVY WOULD HANG A LOBE AND DESTROY THE CAM TUNNEL AND GRENADE THE ENGINE
  • SUPERIOR MOPAR FACTORY DUAL PLANE HIGH RISE INTAKE MANIFOLDS & GREATER CFM CARBURETORS ie 800CFM THERMOQUAD & 625CFM AVS CARBS vs. CHEVY ROCHESTER AND THEIR LOW-RISE INTAKE MANIFOLDS.
  • SUPERIOR MOPAR FORGED STEEL CRANKSHAFTS IN ALLPOLY 318 ENGINES & 1968-72 340'S AND SUPERIOR CAST CRANKSHAFTS vs. CHEVY SMALL BLOCKS.
  • 340'S ARE RARER AND MORE EXPENSIVE THAN THE UBIQUITOUS & INEXPENSIVE 360 WHICH WOULD BE THE MORE PRACTICAL APPROACH "IF" SWAPPING SMALL BLOCKS WAS THE INTENTION. HOWEVER THE POLY 318 IS MORE THAN CAPABLE OF ANNIHILATING A CHEVY 283, 327, OR 350 IN STOCK STROKE & AND IN FACTORY 2BBL. FORM THAN THE 2BBL. CHEVY...LET ALONE IN MOPAR STROKER MOTORS.
  • NOTE: THE HOT ROD MAGAZINE SMALL BLOCK & BIG BLOCK ENGINE CHALLENGES WHERE DICK LANDY BUILT MOPAR SMALL BLOCK & MOPAR BIG BLOCK BEAT ALL FORD & CHEVY BUILDERS ENTRIES BY A SIGNIFICANT HP & TORQUE MARGIN.
  • POLYS MADE FAR MORE HP & TORQUE THAN CHEVY SMALL BLOCKS FROM 1957-1966 ie 1966 283 CHEVY 195HP & 285TQ @ 2400 RPM VS. 1957-66 POLY 318 240HP & 340TQ @2400 RPM AND THE 4BBL POLY 318 MADE 260HP & 350TQ @2800RPM vs. 4BBL CHEVY 283 220HP & 295TQ @ 3200RPM...AND NOT TO MENTION THE 1957 DUAL QUAD FACTORY POLY AT A BLISTERING 290HP THAT FAR EXCEEDED ANY OTHER MGR'S POWER RATING AT THAT TIME AND YEARS THEREAFTER.
  • AND THE 1956 DAYTONA BEACH FLYING MILE RUN WHERE THE 1956 PLYMOUTH FURY 303 cid POLY RAN 148MPH TO ESTABLISH AN UNDEFEATED UNOFFICIAL SPEED RECORD.
  • NOTE: NO MODIFIED FACTORY ENGINE HAS MADE MORE BRUTE POWER THAN THE CHRYSLER/MOPAR FACTORY 1957 392cid HEMI & 1964 426 HEMI. THESE CHRYSLER DESIGNED PASSENGER CAR ENGINES HAVE BEEN USED FOR DECADES IN DRAGSTERS/RAILS/FUNNY CARS MAKING OVER 3000HP...A FEAT NO OTHER "CAR COMPANY" HAS ACHIEVED.
  • MOPARS ARE EXPENSIVE TO BUILD IS A GROSS EXAGGERATION AIMED TO INSULT YOUR INTELLIGENCE AND DISSUADE YOU FROM EXAMINING THE LONG ESTABLISHED FACTS OUTLINED ABOVE. SUCH FANTASY CLAIMS ATTEMPT TO POLARIZE TRUTH FROM FICTION, OBFUSCATE THE PROVEN COST EFFECTIVENESS & BUILD COST DATA WHEN A SIMPLE CATALOG PAGE SEARCH OR ONLINE COST COMPARISON/CONTRAST FROM SUMMIT RACING SHOWS AN AVERAGE OF ABOUT 1O% MORE TO BUILD THE MOPAR 318/340/360 VS. THE CHEVY SMALL BLOCK...ie SUMMIT RACING COST FOR MOPAR EAGLE 6.123 CONNECTING RODS $309 (and even less from other online vendors PERFORMANCE PARTS WHSE $279!) VS. CHEVY 6.125 RODS FOR EVEN MORE CASH @ $317!!! AND THEY ARE "OUT OF STOCK." AND SO IT GOES WITH A PART BY PART COMPARISON CONTRAST WHEN WE ITEMIZE EVERY INTERNAL ENGINE COMPONENT...BUT WHEN YOU REMEMBER THE SUPERIOR STRENGTH CHARACTERISTICS INHERENT IN THE MOPAR SMALL BLOCK DESIGN, CHEVY LOSES THE DURABILITY AND POTENTIAL POWER BATTLE AGAIN AND AGAIN.
  • NOTE: THE BIG BLOCK CHEVY 396 & AND FORD 351C REALIZED THE INHERENT DESIGN ADVANTAGE OF THE YEARS EARLIER MOPAR "CANTED VALVE" POLY ENGINE AND THUS INCORPORATED THIS SUPERIOR MOPAR DESIGN INTO THEIR 396 & 351 ENGINES, ALBEIT NOT COMPLETING THE FULL SUPERIORITY OF THE UNIQUE "POLYSPHERICAL" CHAMBER.
  • NEWER HEMI COMBUSTION CHAMBER DESIGNS ARE VERY SIMILAR TO THE ORIGINAL POLY DESIGN.
  • WHAT TO BUILD IS A SUBJECTIVE MATTER OF TASTE AND PERSONAL PREFERENCE WHILE THE AFOREMENTIONED "DATA/SPECS" ARE FACT AND NOT SUBJECTIVE. I LIKE CERTAIN MODELS OF ALL MAKES OF VEHICLES BUT I CANNOT DENY INHERENT ADVANTAGES & DISADVANTAGES OF ANY FACTORY VEHICLE/ENGINE & DRIVETRAIN DESIGN.
  • WHEN ATTEMPTS ARE MADE TO DISSUADE ME FROM BUILDING A POLY I NOTE THE UNIVERSAL MAXIM: "A MAN PERSUADED AGAINST HIS WILL IS OF THE SAME OPINION STILL."
Vfilms, well said, I have always told my friends that it is the most underated engine mopar ever made. Dave.
 
Great replies Guys!
Special thanx to ‘Vfilms’ for the best reply EVER...:thankyou:

I don’t care about what other folks think is “an easy build”.
I’m more about keeping the car ‘as is’ and in factory trim.
I already got a 71 Gtx six pack with the original engine for Superstock.
Need to know what has been done with a b-bod Poly car?
I used to run mid tens with an all iron 440 in a Dart, (in avatar) it’s not about being the fastest, just wanna be a little different...
 
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ps, looks like a very special UK Moparmate is gonna loan me his Gary Pavlovich supplied 402ci stroker Poly engine built with 4-bolt 340 maincaps, big valve heads and wieand 4-barrel intake...:asskiss:
 
What makes me laugh/cry are the guys that put relatively big money into building a car and then drop in an LS or other small block chev because it’s cheaper.
Can’t count the amazing MOPAR Rods I’ve seen with beautiful paint, great interiors, and a 350/TH350 under the hood.
 
Run of the mill build. Reground factory cam, custom headers, Crosswind intake, small 4 barrel. Simple enough. With some porting might make 300+hp. Or Money, money, money will get you there. If you want to make good power. Stroker, custom pistons. $3K on the heads,. Oh and good luck finding a roller cam core. Might be able to do 500hp for around $10-12K if you do all the cleaning and assembly. Being different is great, just expensive.
Doug
 
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Being different is great, just expensive.
Doug

Piloting an early B body Mopar of any kind at the dragstrip in a sea of Fox bodied, LS powered Mustangs is unique in and of itself! Barely anyone knows what the car is. I've been ready to pull into the burnout box and had people knock on the window just to ask! 99% of the people at the dragstip will not know the difference between a Poly and an RB unless you are at a Mopar specific event.
 
Thanx for the replies.
If going fast is your ‘thing’ then running a b-bod has to be a disadvantage from the get-go?
For me as a lifelong Moparman, the thought of using a small block was unthinkable in the 20th Century.
But I see a lot of newer guys running S/B’s in their B and E bods with great results!
Met a guy from Germany who drove his Challenger 1100 miles (each way) to Santa Pod Uk And ran an 11 second pass...:drinks:
 
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As you may or may not know, the UK is not selling new oil-burning cars after 2030.
Sounds a long way off but that’s real soon for us ‘old car’ fanatics.
How long before the eco’s will want us polluters off the roads TOO?
Trying to meet any sort of ‘emissions test’ with a Bigblock will be almost impossible methinks?

So us ‘new wave’ small blockers will be running 4 inch pistons with ‘Lean burn’ and hopefully meeting the regs OK...
What ever they might be???
 
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Too bad propane was really easy to use and deal with.. or Natural gas ... it’s another can of worms but boy they sure do burn clean!
 
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