cobrabird
Active LVC Member
Any opinions? Worth the effort? Anyone done this? Blower instead?
Stroking the 4v
- Thread starter cobrabird
- Start date
Right on the Mark
Dedicated LVC Member
Common strokes are 3.750 and 3.800. The mod motors don't get the big gains from stroke like the windsor engines. The deal is the 4.6 is square already bore and stroke. The wrist pin will intersect the oil ring and the longer stroke pulls the piston alot out of the bottom of the bore. Some peeps say hey my new forged kit will cost XX and stroker cost little bit more so why not. Also turbos spool better with the longer strokes.
racecougar
Well-Known LVC Member
It really depends on what you're doing with the rest of the engine. The longer stroke will typically limit you to 7K rpm, which can be a hindrance depending on the rest of the build. However, you will see a decent rwtq increase. The bottom edge of the wrist pin will drop 0.155" below the bottom of the cylinder with a 3.75" stroke, and 0.180" with a 3.80" stroke. That places the wristpin CL at 0.278" and 0.253" above the bottom of the cylinder, respectively, as opposed to 0.465" with a stock stroke crank. Therefore side load that the rod places on the lower cylinder wall is increased slightly with the longer stroke. However, there are thousands of Saleen's with this geometry and no apparent warranty issues. There are also thousands of us who have gone the stroker route and had nothing but good experiences. I run a 3.75" stroke Mahle piston/Manley rod rotating assembly from Livernois in my blown 4V.
Also, the wristpin does NOT intersect the oil control ring on any decent kit.
Also, the wristpin does NOT intersect the oil control ring on any decent kit.
Right on the Mark
Dedicated LVC Member
It really depends on what you're doing with the rest of the engine. The longer stroke will typically limit you to 7K rpm, which can be a hindrance depending on the rest of the build. However, you will see a decent rwtq increase. The bottom edge of the wrist pin will drop 0.155" below the bottom of the cylinder with a 3.75" stroke, and 0.180" with a 3.80" stroke. That places the wristpin CL at 0.278" and 0.253" above the bottom of the cylinder, respectively, as opposed to 0.465" with a stock stroke crank. Therefore side load that the rod places on the lower cylinder wall is increased slightly with the longer stroke. However, there are thousands of Saleen's with this geometry and no apparent warranty issues. There are also thousands of us who have gone the stroker route and had nothing but good experiences. I run a 3.75" stroke Mahle piston/Manley rod rotating assembly from Livernois in my blown 4V.
Also, the wristpin does NOT intersect the oil control ring on any decent kit.
Going to guess you have 1.200 CD and 5.850 rod?
94m5
Dmaup's Daddy
Love the 5.0 4-valve in the Cobra.
no replacment and all of that.
no replacment and all of that.
racecougar
Well-Known LVC Member
Correct.
cobrabird
Active LVC Member
Pretty car and PRETTY engine!!!!!
How much of a pain is it to build the 5.0 stroker? What kinda of horsepower would I be looking at?
How much of a pain is it to build the 5.0 stroker? What kinda of horsepower would I be looking at?Right on the Mark
Dedicated LVC Member
Pretty car and PRETTY engine!!!!!
Its no different to build then a 4.6 .