evosnstuff

iTrader: (2)

im running comp 280/280s with a 35r kit. i still have stock valvesprings and retainers. my car only has 10k miles on it, so spring pressures probably like new. how crucial is it that i build the valvetrain ? is this something i can hold off on for a little. lookin for some opinionsssss

oh yeah 05 evo 8 btw

ctfpevoVIII

iTrader: (4)

seeing that you have a 35r kit and the powerband gets moved up I would throw some better springs and retainers in there if your going to go past 8000 rpm often. If you going to keep it under 7500 rpm your probably be fine.

MechTech

You should upgrade your spring and retainers asap. Even if your spring are like new they still are insufficient with 280s, surprised you havent had an issue.

mrowka

iTrader: (6)

stupit question, but what's the point of a big cam if you're not going to rev to the stratosphere on a regular basis?

big cam + lo rev = worst of both worlds

ctfpevoVIII

iTrader: (4)

Well you don't have to rev the **** out of it all the time, but its nice to know that you can when you want to. Also it sounds awesome when your idle has some lope to it.

EVOinaDSM

For the extra ~ $200 for some aftermarket valve springs it's worth the upgrade, valve float can cause some expensive mistakes. Pick up some BC or Manley springs and call it a day, then sell your Evo beehives to somebody with a DSM on a budget who's still running stock or super mild cams

blackenedwings

Absolutely, for the cost for the springs its 100% worth it. I went with stock valve springs when I first did my cams and spiked the rpms once at NJMP and caused damage. Do it while you have the cams swapped it will save you money in the long run.

www001510565

iTrader: (1)

gonna install my kelford 272 soon with some supertech dual spring and retainers just to be on the safe side.

ctfpevoVIII

iTrader: (4)

good choice and very wi$$$e decision.

RealStreet

iTrader: (1)

smart! valve float is a terrible thing my friend.

mrowka

iTrader: (6)

Sure, but if you have a valvetrain that is limited to 7800 or whatever, you aren't going rev it to the stratosphere regardless.

Sunwalker12

As a general rule of thumb, anything above 272s, upgraded valve springs and retainers are critical. I havent built too many imports but have plenty of experience on domestoc V8s; however, a larger camshaft improves performance by opening the valves at a different point throught the RPM band and holds them open longer to allow for added air flow. With aftermarket camshafts your sacrifice comes from the lack of low-end torque and moves the powerband to, typically, to a higher range. Because the lobes on the camshaft are longer and contain a higher duration and different lobe seperation angles the factory valves can be extended beyond their tolerence and thus the comment was made earlier about "valve float". When surpassing a cam that overextends the factory design function your limiting the life of your valvetrain and comes down to a hit or miss everytime you row through the gears. Factory camshafts and valves are more than capable of reaching the 8k mark but because of the increased strain on your valvetrain youve limited yourself to lower RPMs...defeating the purpose of moving your powerband, you CANNOT take advantage of your modification until you modify the valves. Im confused as to why you spent the cash on the cams but didnt upgrade your valvetrain, especially when it was already torn apart. I would drive her easy until you upgrade as floating a valve would be bad news, head/piston damage....serious mods require the application of supporting hardware, you wouldnt throw on a 60 trim using tge stock intercooler and piping (youd be blowing hot air and the potential CFMs would be hindered by the restrictive piping not the mention the pressure wouldnt be tolerated by factory worm clamps)....hope this helps

ctfpevoVIII

iTrader: (4)

What valvetrain are you referring to? If you upgrade your springs and retainers along with some cams that breathe up at 8000 + rpm then you may want to rev real high. If you mean stock to mild cams then yes I agree , theres no point in revving it higher if its not producing more power.

mrowka

iTrader: (6)

I wasn't referring to the cams but to the springs as the limiting factor; no point in putting on a cam that only makes power when it is revved to RPMs that your springs and retainers don't want to go to.

evosnstuff

iTrader: (2)

thanks for all the input guys, im definitely going to order my springs and retainers on friday. i bought the car with the cam in it. any other suggestions on manufacturers i should go with?