disposer

i am thinking of getting the comp 918 springs, i have see some people shimming them for about .050 but i didnt understand why!

my question is what is the Max valve lift that they can hold if they were shimmed to a .050 ?

PS: my shift point will be around 6800-7000 RPM

thanks for the help guys

oh i almost forgot, from where i can get the .050 shims ?

xfactor_pitbulls

iTrader: (16)

Not shimming .050, but shimming to within .050 of coil bind. Brian I forget off hand, but isnt the coil bind right around .700? So if you were say running a .620 lift cam you would want to shim about .030.

Brandon

disposer

i didnt get the cam yet but i am thinking of getting the G5X3 or G5X4
or some similar cams

i have a 98 camaro ss with a 383 ci, M6 but it will be swaped to a TH400
so the new camshaft is going to be for thew new tranny, thats why i have to choose the camshaft first
the car is going to be mainly for a strip use and little bit of street races

777

iTrader: (21)

Any reason you aren't going to go with a nice dual like the 921, prc's, or patriots?

disposer

the 918 are beehive so i am going to save some valve train weight, that means more power, thats all
.. well what do you think guys should i go with the 918s or the 921s ??

xfactor_pitbulls

iTrader: (16)

What cam?

Brandon

AgFormula02

iTrader: (13)

A double spring may cost you some power due to added valve train weight, but as long as you use TI retainers, the difference is minimal.
Spend the money and get a true double spring. It is cheap insurance against Mr Piston meeting Mr. Valve.

SideStep

Cool....

PREDATOR-Z

918 Tit retainer is at 7gr
My PRC dual tit retainer at 11gr

oange ss

iTrader: (50)

did you use the PRC springs or the 918's ?

PREDATOR-Z

I ran 918's cam only on 241 stock heads for over 10+K miles; just last week, I installed a set of PRC stage 2.5- 5.3L heads and they came with PRC "platinum" dual springs and an extra retainer lodged in one of the water passages.
So yes, I run PRC's right now.
PRC "Platinum" are good to .670 lifts advertised.

oange ss

iTrader: (50)

do you see any reason to run the PRC springs instead of the 918's on a 224/228 .588 cam ? the 918's also have Ti retainers and were used less than 1000 miles, oh and I also have PRC 2.5 heads

PREDATOR-Z

If the heads are allready assembled with the PRC springs, then leave them as is and install them. Why bother, there is no real negative effect with a small cam like yours (or mine).
I would put new 850-16 lifters on (Comp Cam) as extra safety.

oange ss

iTrader: (50)

i just dont see the point in runnin those big springs with a "small" cam, I also wonder if the 918's will have any problems controlling the heavier valves and of course the added stress on my stock lifters is also a concern, but I see no reason to replace them with only 35,000 miles on the clock

98A4LS1

iTrader: (1)

I was wondering the same thing, stiff dual valve springs on a small duration/lift camshaft. Wearing out the cam lobes and lifters quicker?