I am debating on whether or not to do a 403 Stroker and am curious from the stroker G8 folks how it drives and what are the cars manners.

 

This is not a G8 specific question. A 403 stroker can be built to drive as mild as a factory car or as radical as you want. It's going to depend mostly on camshaft selection.

 

Really? I figured throwing .6L of displacement would alter the characteristics of it. What is the threshold for mild but good street performance? The Cam I am looking at is a 229/236 .629"/615" 112 LSA. Possibly bumping upto a 113 LSA to pair with the 403.

 

Stroker means you increase crank throw wo it pulls the piston down further in the cylinder thus adding lots of air to each combustion cycle. The added throw also increases leverage on the crank thus adding more torque. Adding torque all across the powerband will of course increase driveability. Car will be much quicker around the streets and with increased throttle response with low throttle input. You will want and induction system/heads and a cam to match the stroker for the increased displacement. Bigger displacement motors are less sensitive to valve overlap and a bigger cam must be used to get the same characteristics as a much lower displacement motor. A nice daily driveable but more aggressive for the daily driver category cam for a 403 would be a 236/245 112 cam whilst in a 5.7/6.0 you'd probably like a 228/232 114 cam.

 

So I would need a much more aggressive cam just because I am making the engine bigger? As a daily would a stroker kill the the MPG?

 

Yes, especially when you stomp that right foot! How much MPG you lose is up to you but your mileage will drop.

 

Strokers are actually very very drivable. Check with your builder to see if the deck height of your motor and your cube goals are compatible. I had a 408 stroker and put 20k on it before the truck was sold. The way mine was built it was torque for days and not much of a peak. It was a great motor built for towing and mountainous highway cruising. Not a dyno sheet motor. But it could have been with a bigger bump stick. It wasn't a car but I think it answers your question better.

 

i did this years ago. stock heads ported and a mild cam with a 116LSA and an LSX Intake. only mistake i made was not putting a converter in it. when it was cool out it would surge until warm.. at stop signs and quick braking to a stop and it was not enjoyable.. so keep that in mind if you live where it can get cold (30f and lower).

used a manley ultra lightweight rotating assembly. it revved like a 4cyl.. was very fun.