Does anyone know what the stroke is on the 3.1L and 3.4L engines?

Also does anyone know how much room there is to increase the storke? How about if there are any Crank shafts out there that will fit in these blocks that will in crase the stroke length? Or will I have to look into a custom crank?

Incrasing CID by incrasing the stroke should yeild more TRQ vs. incrasing the bore.

 

http://www.60degreev6.com/

On left navigation menu, under 'Motors' click 'Pushrod', click large 'Specifications' button, check differences between 3.1l Gen 1 and 3.4l Gen 1.... .... which are apparrently the same page, by some mistake on the part of 60degreeV6.com... damn someone for not double-checking their work. Anyway, they're the same stroke, difference is bore

 

Increasing the stroke will lower the RPM potential of the motor, BUT it will increase torque potential.

 

Either will handle over 8000 RPM when balanced correctly and built right, so I don't see this being something 99% of us care about. The torque increase we probably do, though.

 

I've already notified 60DegreeV6.com of the problem with their specs page, btw, in case anyone else felt like doing it.

 

Yeah before posting I was looking around thier site. The 3.4L spec page is exactly the same as the 3.1L spec page so it was no help.

How about the crank shaft does any one know of any that have a longer stroke that fit in the block and not strike the oil pan? Or of place that will make a custom crank?


If it doesn't lower potentional RPM to much it would be prefect for me.
To tell you the truth I never take it above 4500 RPM. Well a couple times I did it by mistake, but that's what rev limiters are for.

I think the incrase in torque would make it worth it to lose RPM potentional. Build your torque and HP will follow. Hell these engines lack low end torque to begin with.

 

The reason(s) our motors don't want to spin up over 5k is because the exhaust, intake, and camshaft are all holding the motor back.

3.1/3.4 = 3.31" stroke.

 

I'm leaving the factory 3.4L 3.31" stroke.

Going to a 6" rod so I can run higher rpms and higher CR, fatory is 5.7"

Going to .040 over on the bore. Factory bore on a 3.4 is 3.62". I am going to 3.66. The block can handle up to 3.68 safely, 3.69 is pushing it.