1dirtyZ

iTrader: (1)

everytime i nail the car to the 6400 redline and let off the car starts making claking noises ( real loud valvetrain noise) but it just goes after a minute or so.

i'm assuming my lifters are collapsing and slowly filling up after WOT. why is this happening?? what can i do to aleviate this situation??

my current setup is 220/226 and .564 /.569 114 lsa, crane 1.8 rockers, 918 springs.

HITMANSS

My guess it's because you are using 1.8:1 rockers on a high-lift cam.

chino_man279

iTrader: (7)

IMO it is from what hitman said also. Ditch the high ratio rockers and put some stockers back in. The problem will probably go away....
Joe

horist

I'd have to say the same... stock lifters, higher RPM and fast ramps coupled with the fact that your lift is .597/.602 now... a bit much for stockers I think...

robertbartsch

Question: WIll lifter collapse also occur as a result of using bigger valve springs?

I'm going to swap out to some Lunati REVs doubles that have a lot more pressure than stock. Most people I assume continue to run their stock (old)lifters when doing a H/C change. Why?

Skelton

Bigger springs will probably increase the problem. 1.8's on an xe-r grind will make for some seriously fast accelerating valvetrain and bigger springs will just increase the pressure on them. I would also check lifter preload to make sure its not too little or too much. That can create the same problem since it can beat the lifter down. Make sure you ck the lifter preload also.

bdawg/98mechamta#9

clean "em dirty ! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

MyLS1Hauls

iTrader: (2)

Having higher ratio rocker arms increases the load put on lifters. Since the spring pressure is multiplied by 1.8 rather than 1.7.