4.8 Mega-Torquer Stroker Rotating Assembly Kit
Introducing our Mega-Torquer 4.8 AMC/Jeep 4.0 based Stroker kit, which includes: 4.060" Stroke fully balanced Eagle crank, 6.125" SCAT bushed connecting rods, 14cc dish custom designed coated hypereutectic pistons, 1.2/1.5/2.5mm low tension rings, King main and rod bearings, with ACL cam bearings to avoid the dreaded cam bearing failures of all other bearings.
You will not find a better, economical, piston and ring combo on the market that covers so many applications, such as: Daily drivers, weekend warriors, racing, boosted applications. There is no piston to valve clearance issues to worry about unless extreme head milling or high lift/duration cams are used.
We have built many different combos with these from extremely small cam combos to whopper cam combos. The minimum Hp made to date is 350hp and the most naturally aspirated is 428hp and over 700 boosted.
Modern designed rings(1.2/1.5/2.5mm) and it shows. When you compare shortblock turning torque and sealing properties there is no comparison. A normal fresh built factory style shortblock will have a turning torque of anywhere from 24ftlbs to 32ftlbs. Our bushed piston and ring package even with the longer stroke takes only 12ftlbs-16ftlbs to rotate and the sealing properties are awesome.
All of this means less wear, better sealing, less drag for much more power. You will need to have a quality machine shop set piston to cylinder wall clearances and deck block accordingly.
Compression ratios will differ depending on deck height, combustion chamber size, bore size, gasket thickness. Do your research on your exact combination. Here are a few example:
Bore-3.905"/Stroke-4.060"/Gasket Thickness-.041"/Deck Height-.000"/Dish-14cc/Chamber Volume-63cc=10.33:1
We prefer the following Piston/Ring clearances:
(Street) Wall clearance: .002"-.003"/Rings: Top .018"-.021" Second .018-.022"
Scrapper .015"(Minimum)
(Race) Wall clearance: .003"-.005"/Rings: Top .021"-.024" Second .022"-.026"
Scrapper .015"(Minimum)
(Boosted) Wall clear: .003"-.006" /Rings: Top .022"-.026" Second .024"-.028"
Scrapper .015"(Minimum)