punishmentcycle

iTrader: (6)

why did u go with such a big spring? the sound might be the valves slamming closed alot harder than they should

wcryan

iTrader: (2)

It's not coming the the valve cover area though. That's why I think it might be the lifters. Those were just reccomended to me because of the success they have had with them

ichpen

Is it these springs?

http://www.texas-speed.com/p-474-pre...pring-kit.aspx

BTW, speaking from experience (having pulled the motor for a rebuild on no less than 2 occasions, sigh) there's almost no scientific way of figuring out where ticking is coming from. Not with the reverb halls that are our aluminum blocks. I've had tens of experienced mechanics and engine builders try to figure out the issue from above but in all cases were wrong. Pulling things off is sadly the best way.

wcryan

iTrader: (2)

yeah, I think it's those

Cunningham is going to go from the least invasive to the most invasive

So we'll see what it is when they are done

ichpen

Pray it's not what I had...

wcryan

iTrader: (2)

a bad cam? I kinda want a new one. haha

itsslow98

iTrader: (18)

Boosted cars need a tougher spring anyways.

wcryan

iTrader: (2)

Elaborate on that Allen. Seriously. I'm not trying to pound u like everyone else does on this forum. I just wana know

itsslow98

iTrader: (18)

High cylinder pressures with boost. Weak valve springs cant handle it.

wcryan

iTrader: (2)

so your saying the .650's were a good choice?

But not only that, an ok choice?

I dont want springs that will **** up my setup. I dont think the boys at cunningham would set me up for failure

ichpen

You know my story. Heavy springs (mine were v similar to yours, maybe a tad heavier) essentially caused very premature cam wear and a couple of morel lifters to take on some face paint as a result. This is daily driving, not on the track. Not saying that happens to all but my engine builder (who seemed to know his crap) was very insistent to be careful with dual springs (as they are inherently heavier with more seat/open pressure), and only use them if I absolutely need them.

I'm also always confounded by shops that sell kits with light titanium retainers, lighter rocker arms etc etc, designed to lighten your top end then slap on a massive/heavy dual valve spring. Makes no sense to me.

You can get lighter duals or good singles.

Onefast V

iTrader: (3)

While this is true, 145# of close pressure is extremely higher than the stock 95#. On a lower lift cam with boost he should need to run more than 120# of closed pressure. too stiff of springs will cause failures.

ichpen

Correct. 120 on the seat and under 400 open is what you should be aiming for.

itsslow98

iTrader: (18)

I wasnt necessarily saying that the springs he was using were ideal, but a cam with 560 lift and boost wouldnt be good with springs rated for 575 lift. Also all dual springs witha lift rating and titanium retainers are not created equal.

Patriots for example use titanium retainers that are considerably heavier then a set of PSI springs with titanium retainers.

heavymetals

iTrader: (3)

Check this:

http://forums.corvetteforum.com/c5-t...ity-party.html

YEOW!

wcryan

iTrader: (2)

^ ouch. Hopefully mine isnt like that

ichpen

Mine was quite similar, not as bad and none of the lifters were that worn down but yeah cam lobe was toast. Wish I kept a pic but changed phones and lost a bunch of pics.

Expensive lessons these.

wcryan

iTrader: (2)

Ive already stopped driving it. It's gonna sit till the 9th

9t8z28

iTrader: (19)

Sounds like incorrect length pushrods. Not a big deal.

ichpen

It might be if he's been running them for a long time and ticking developed recently.