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STROKER issues

Ok,,
so if you stroke an engine then basically the center line of the crank journals are further from the center line of the rod journals due to how the crank is made.  Therefore,, the rods must be longer and pistons will be shorter.

So if you were to compare two sepeate engines,, say a 3.8L and a 4.2 liter,,, and you have any one piston all the way down,,, wouldnt you expect the 4.2L to be sitting deeper in the cylinder than the 3.8?

My factory shop manual for the 3.8L calls out the stroke of a 3.8 to be about 3.3 inches.

I measure on the 4.2 liter from the block deck to the top of the piston and i come up with 2.9XX

Whats going on here?  Its seems the stroke is shorter on the 4.2 compared to the 3.8!!!

STROKER issues

Reply #1 –
The stroke of a 4.2 is 3.74 inches. Better get that tape out again :D
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

STROKER issues

Reply #2 –
I am measuring from the deck to the piston top,,,,

i used my depth guage on the dial caliper

sorry but i really am confussed here ,,,badly

STROKER issues

Reply #3 –
I have a friend who is an engine builder, ill ask him how to measure stroke, because i dont think thats the proper way.
It's Gumby's fault.

STROKER issues

Reply #4 –
of course thats the way you measure stroke,, the center line of the crank to the center line of the rod journals.  Now having said that,, the distance of the centerlines has no choice but to be transfered to the distance from the deck to the top of a piston that is BDC.

IF,, for instance, you have a crank to rod centerline distance of 1",, then the piston would only be able to move a full two inches of distance if you measure from the deck to the top of the piston when its down.

STROKER issues

Reply #5 –
Have you gotten anywhere else as of yet? I will have my yahoo on later tonight if you get bored again.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

STROKER issues

Reply #6 –
find anything new out?
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com
 

STROKER issues

Reply #7 –
oops found it in the other thread. Good luck!
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com