I am looking at doing a 383 stroker potentially in my porsche 944 but I need a few pieces of data. I am especially curious as to MPG since I've heard it isn't effected much by stroke.

1.MPG before and after stroked.
2.What your current setup is.
3.What are your dyno numbers tq/hp before and after. (1/4 mile or 0-60 could also work)
4. Have you autocrossed or road raced your car and is a 383 a good choice for a road car?

 

in for info as well. trying to decide what route to go with my engine build.

 

I talked to texas speed and they said it would be a good setup for autocross/road racing. They seem like a very knowledgeable shop. They estimated a mild cam with a 383 setup would stick me at about 25mpg in a corvette on the highway but this was all ballpark.

Anyone have straight data?

 

MPG info I haven't run across but interms of everything else you want there is a ton of info on this board. Just do a search for 383. I have a block I am planning on building a 383 out of as well. It's a pretty popular and affordable setup.

 

MPG is dictated mostly by aerodynamics and drivetrain efficiency, with vehicle weight playing a roll in city from accelerating the weight. That said displacement and HP don't have a big effect, even deeper gearing usually isn't a big deal.

The constant is still the work the engine needs to do to push the car through the air.

 

Going from a stock LQ4 6.0 to a 383 (6.3L) I lost 1 mpg highway and about 1.5 mpg city. I'm at 9/12 now.

 

very true, however with a more powerful engine the driver is using more energy accelerating the mass of the car faster than normal. Even on the highway when you pass cars, etc. That is where the extra energy goes.

 

1. 23 and 19 but who really cares
2. Car I used to have but it was a stock block, Manley crank, diamond pistons, Callie's rods, custom cam, and compression at 11.1:1
3. 424/392 on motor (11.9@113) 540/500 on nitrous (11.2@125) before 453/424 on motor (11.6@118) 640/580 on nitrous (10.90@133) after


Car was never setup to be a drag car so times could have been better but it didn't interest me that much.