I built my 408w stroker with 10.5:1 because of the way they change the ethanol blends between winter and summer..
Im also running a camshaft that delivers max torque and engines built like mine are pretty prone to popping an upper ringland when powering the engine up from down low and cylinder pressure goes through the roof....If I ran 11:1 Id have to run atleast 97 octane...
The reason why I built it that way is because its pretty fun when you dont rev any higher than 5500 yet your up over 100mph running next to a guy whos screaming 6500-7000 rpm's and it doesnt sound like I'm racing down the highway....
Ive been cited for reckless driving in my 69 Olds442 w/441cuin SBC w/a 350turbo transmission w a 4000 stall converter ,purple hornies attached to longtube headders and a 411 rear quite a few times and paid hefty fines.. When I hit the gas to get the car moving when the light turned green it sounded like I punched the gas off the line...I tried explaining to the cop about the camshaft n converter plus gearing and he said tell it to the judge....LOL
Now I build my performance engines for the street with such brutal lowend torque they get up to speed really quick n effortlessly through the
Magnaflow cats n the mufflers and it doesnt even raise an eyebrow of the local fuzz yet Im still having fun plus also saving my valvetrain from heavy high rpm abuse and always having that feeling like its futile to defy gravity by being sunken into the seat with some nice force is a pretty awesome feeling without the diesel smell or the black soot..........LOL
From 3100 - 4400 rpm's my 408w on a carb on the dyno was belting out from 568 down to 535ftlbs of torque yet only putting out somewhere between 327 -350hp...At 5500 the engine is pumping out 509ftlbs torque and 464hp. Not one time does the torque and hp crossover on the graph either.....LOL
Im running it with a QH and EFI also a TKO600 w/.64 overdrive and a 3.55 gearing too....
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