rod to stroke ratio

[GasSavers_RoadWarrior]

I'll have all hotspots eliminated (I hope) and a homebrew thermal coating of sorts. With that and the purported ability of singh grooves to prevent detonation, I'm hoping to be running 87 octane in it. If not, I'll mess with the cam, or use an octane booster. Also have another idea I'll be working in that looks like preventing detonation in addition to what I aimed it at.

[rakkassan34]

one of the benefits of a long stroke short rod combo. The piston doesn't dwell at TDC long so your dynamic compression ratio isn't very high meaning you can run higher static compression ratio pistons. A camshaft ground to take advantage of this can further help prevent detonation.

Imagine if you do hit the 300hp mark with that combo. You could build a similar smaller engine pushing 150-200hp further increasing mileage.

[DRW]

How about sleeving the motor to reduce the bore? You'll need custom pistons, too. The benefits are less friction between piston and cylinder, a better bore/stroke ratio, and lower piston weight. http://www.lasleeve.com/master.html
I did a quick check to see how small the bore could be made in my engine. The stock bore is 85mm, the smallest sleeve that fits would make the bore 79mm. I'd call that a significant change.

[DRW]

Originally Posted by theclencher

Would the valves still work?

D'oh!
See what happens when I daydream?
I just happen to have a spare cylinder head here. The smallest bore that would still fit the valves is approx. 81mm. 4 valve heads tends to use almost all available space. I guess a smaller bore could be used if the upper part of the block/sleeve was notched or radiused at the corners to allow clearance for the valves.

I just took a look at a spare G54B head I have, too. The smallest bore that would fit it's valves is approx. 82mm. Not bad.

Roadwarrior, does Marvin have a G54B?

[GasSavers_RoadWarrior]

No he has a 6G72, V6, bore is identical to G54B though.