Hey all, I hear a lot of talk about 'stroker' engines?

Can anyone define a stroker engine for me?

Cheers

Basically it's an engine with a longer than standard 69mm stroke

anywhere from 74mm up. Requires some clearancing of standard cases.

Not sure max stroke using standard case. Ive seen cranks with 94mm stroke

Whats the whole idea behind the longer stroke?

more torque *usually* as more swept volume = bigger pump = more grunt.

Again basically...bore x stroke = engine capacity

eg 69mm stroke x 94 mm piston = 1916cc

74mm stroke x 94mm piston =2054cc

You also get an increase in torque from a stroker crank because of the longer lever. This is good for the drags

everything appears stock too, you cant 'see' the bigger crank, so if you were the less sporting type and racing in a set class, you could sneak a stroker crank in to give you that bit more grunt. Nowadays you would get scrutineered but in the bad ol days.......

kkk

The maximum in a standard case is 86mm although most supliers do not usually stock any larger than 84mm.

These cranks such as 82 and 84mm ....capacities such as 2180, 2275 and 2332 require clearancing of the case at the top and sometimes the cam as the crank will touch when it rotates. the rod length will also change as will the pin location in the pistons.

You can get 3 general types...welded, cast and forged.

See scat, cb performance or geneberg sites for info on their stroker cranks.

They do make lots of torque and in a big capacity around 2.2 litre, with the right combo of carbs, cam exhaust etc, can be ridiculously quick...... All comes at a cost though. A good combo setting you back between $6000-$10000 depending on heads, case etc.

Hope this helps..

Matt

Yes I must concur with Boof2332, the torque is quite something, when you take off from a standing start you and the seat of your beetle become one.

Ah I miss my 2110.