mats

Hi

When reading tests where 2 stroke engines are compared with 4-stroke engines with the same hp on a particular boat, it appears that the 2-strokes accelerate faster. Is that so? why?

BadDog

Bang, Bang vs Huff Bang Huff Bang

Ric232

Two reasons:

1. 2-strokes generate power on every stroke (i.e. bang, bang, vs huff, bang, huff, bang), therefore they generate great low-end torque.

2. 2-strokes weigh less

Ya' know, I wish somebody, just for kicks, would build a 500+ cu in 2-stroke motor. That would be one friggin' scary monster.

doright

Yeah, and it wouldn't use much gas either.



/goes to hell for lying.

28Eliminator

Ya, but it would be a fun scary monster.

Mr. Demeanor

A real good comparison of the two is going on in GP motorcycle racing right now. This is the first year they are allowing 4 stroke GP bikes. Interestingly, the new fours are running a tad faster than the old bikes. They changed the rules to get more of the "Win on Sunday, sell on Monday" incentive to the manufactureres. Should prove to bring some interesting new tech to the street in the years to come.

Highmark

If you compare CC to CC 2 strokes produce more horsepower. There is a reason why in motorcross they let 250 4-strokes (Thumpers)race in the 125cc class and 450's race in the 250 class. Besides the fact that they fire every stroke of the piston there is the weight factor. Two strokes do not use valves, cam's etc. are are much lighter per CC. Wasn't there a post or something on the main page showing a new setup using twin 300 HP two stroke inboard engines with surface drives or something? I bet that would be one wicked boat with that much power and that little weight.

JUSTONCE

Alot of the older big diesels are 2 stroke. they burn dirtier.