just bought a ke25 and a valve cracked, got a new 5k head but has double valve springs, could i bolt onto th old block even though it has hydraulic followers? please help asap.

So your ke25 currently has a 3k in it with a cracked valve?

i hope so, my 5k is running hydros with crow springs, it should work, what cam are you using?

nah its a 5k block and head. i wasnt sure if i can replace the old springs to double valve springs with hydraulic lifters

Is the old block a 4K or a 5K? Does your current motor have dished or flat top pistons? Valve springs are just there to keep the valves sealed doesn't matter how many there is, they'll just give your motor more potential to rev (if everything else is right) and waste a little bit of power if they're heavy duty.

 

The important thing is to run the head with the right dish volume so you don't end up with compression high enough for methanol, around 14-15:1 with a 5K head on a 4K bottom end.

running stock cam? i think ther double valve springs from a holden.

i don't think its necessary to use double valve springs on a stock cam

its 5k block and dished pistons and the inlets hav been bore'd, not sure if that helps.

Cool, as long as the head came off another dished motor you're laughing. Put the 2 heads side by side. If the replacement head is 1.5-2mm shorter it'll put the compression up too high, similar height all good.

or you could check the casting number? or lugs under the spark plug holes?

why would you want double springs, when standard 5k springs will handle 8000rpm.....

Also stock 5K springs are heavier than normal 4k/3k/2k springs :) And yes will handel over 8000RPM.

 

Cheers

Cameron