Is it possible on an s2k while keeping compression up? just wondering... it might be good for the track just in case of mechanical over-rev... even as a street safety precaution. maybe in a FI application?

 

I have no clue what you are talking about.

 

as in the valves wont touch the piston during over-rev

 

they hit..... def seen it more then once, and there is no real way to stop this from happening. its in the way the motor is built when they are both extended all the way out (like in a miss shift/ over rev) they will hit no matter how stiff the springs or how much you mess with timing.

 

I think what he's getting at is whether or not it would be feasable to increase the headgasket thickness until there is enough clearance between the pistons and valves so that during over-rev or timing chain failure they would not come in contact.

This would probably only be an option on a FI setup where the loss of compression could be compensated for with boost.

So the question becomes...how much overlap is there and can you get a headgasket that is > that number?

I don't know.

 

Crack kills.

 

LOL... if you are referring to me... shut up! (j/k)

 

[QUOTE=axhandler,Sep 22 2005, 12:44 PM] I think what he's getting at is whether or not it would be feasable to increase the headgasket thickness until there is enough clearance between the pistons and valves so that during over-rev or timing chain failure they would not come in contact.

 

If you are thinking about making the S2k's engine a non-interference motor, give up the dream.

The only way it's going to be non-interference is to drastically reduce valve lift, and big compression ratio loss.

So you'll have the only 125hp S2k that won't bend a valve from being overeved.

 

Maybe a side valve motor? They were all the rage 80 odd years ago.

Seriously the solution to mechanical overrev is learning to drive.