Upgrading valve springs

[TRD_ZERO]

Ok so i dropped my head off at the cylinder head shop today and explained what i wanted done. He asked what my application would be and i told him turbo blacktop 20v he asked how much boost id be running a said 10ish daily and 20 max for abit of fun. He told me that the valve spring wouldnt be able to handle 20psi..........so now what didnt gasman run factory valve springs on 20psi? And i think maybe even flygt4

[Chasermk2]

you definitly should replace to aftermarket springs if you are running 20 psi!

[TRD_ZERO]

Didnt gasman run factory valve springs on 20psi? And i think maybe even flygt4

[escortman]

it is recommended that u do it my engine builder said i he ll test them and they were all around 30-35psi, so if they 2 soft and ur running big boost the valves can lift and ull lose boost etc, so i got kelford cams 1s was about 300 for them but theyr about 55psi

[TRD_ZERO]

Valves cant lift? Dont they get pushed down? So if the spring is too soft too much boost will blow it open? or wont seal properly?

[Chasermk2]

how hard the spring is determines how much lift you get, too soft spring = too much lift and you lose power etc. they used to replace the springs with solid spacers on old racecars.

[rollaholic]

change 'bit of fun' setting to 17-18 psi

profit

[AceSniper]

if your running stock cams you could use thicker shims under the springs than the std .5mm ones... may add a bit of safety? just make sure you don't go to thick

[TRD_ZERO]

change 'bit of fun' setting to 17-18 psi

profit

Now my "bit of fun" setting doesnt sound like so much fun anymore.......but still my question is didnt gasman and flygt4 run factory springs on 20psi?

[escortman]

u can run stock 1s but y not do it all now

[bluemaumau]

why dont you pm them?

i was under the impression you needed to upgarde at around 2 bar?

in saying that its a engine, it depends how much fatigue stress its had(springs) who knows they could crap out at 15 or 50psi

[escortman]

yeh get them tested 1st

[TRD_ZERO]

u can run stock 1s but y not do it all now

Because of the cost of it, new ones are around $300. Like i dont have other expenses

why dont you pm them?

i was under the impression you needed to upgarde at around 2 bar

Pm them? The head specialist sad anything over about 15psi needs uprated springs. He is a head specialist he does this for a living is he wrong? But then how is gasman and flygt4 getting away with it?

[matt dunn]

Pm them? The head specialist sad anything over about 15psi needs uprated springs. He is a head specialist he does this for a living is he wrong? But then how is gasman and flygt4 and matt dunn getting away with it?

I run factory valve springs and 20psi all the time.
haven't had a problem with them, running with standard cams.

but the engine builder also had my aftermarket cams when we first built the engine and said that they would be fine, but were very close to coil bind with the aftermarket cams.

[escortman]

u can run stock 1s but y not do it all now

Because of the cost of it, new ones are around $300. Like i dont have other expenses

why dont you pm them?

i was under the impression you needed to upgarde at around 2 bar

Pm them? The head specialist sad anything over about 15psi needs uprated springs. He is a head specialist he does this for a living is he wrong? But then how is gasman and flygt4 getting away with it?

yeh but its more money if u find out on the dyno when its gettin tuned that theyr to soft, but there are heaps of ppl running stock tho

[gasman]

im actually not running 20psi yet, but flygt4 is definitely running 20psi. im currently only running 16psi, i never actually considered upgrading my valve springs and overlooked it because others didn't upgrade them.

according to my calculations at 20psi the approximate force behind the valve is 76N or 7.6kg, if you get ur springs tested and it the spring force in the seated position is far more, then u should be fine and valves wont lift.

[Bazda]

I had to get upgraded valve springs.
I did heaps of dyno runs on 25psi and it was fine, did about a weeks driving on 20psi. Then one day it got valve float and bent the valve.

So I upgraded springs and have never had an issue.
Also when I did upgrade them the car felt much much stronger at high boost levels!!

[MAGN1T]

Valve spring tension has got nothing to do with boost. Revs , yes. Think about it. How can they blow open?

I found a spec of 35 pounds seat load minimum for a 4AGE to run at 7700 rpm. So if you work out the valve head area (about an inch in diameter, .78 or so square inches)convert to PSI, the intake valve will blow open if boost is more than ????? and that's only with boost in the intake manifold and vacuum in the cylinder

He's BSing you to get a sale. How do people get sucked in?
You need a large fries with that order otherwise it won't taste nice.

Stock springs can be tested, there's a certain spec for seat load (pounds not PSI). If needed you can shim them for a bit more seat load , so long as you don't have too much lift which could cause bind.

Steve

[Jdawg]

You can get the springs tested on spring tester or ball park by measuring free height. Your cam manufacturer should be who you consult about springs

[TRD_ZERO]

Pm them? The head specialist sad anything over about 15psi needs uprated springs. He is a head specialist he does this for a living is he wrong? But then how is gasman and flygt4 and matt dunn getting away with it?

I run factory valve springs and 20psi all the time.
haven't had a problem with them, running with standard cams.

but the engine builder also had my aftermarket cams when we first built the engine and said that they would be fine, but were very close to coil bind with the aftermarket cams.

Sorry i didnt deleberatly forget you, i actually thought of you but saw you had already posted.

I wont be running high psi all the time and its not going to be my daily either. Im just not wanting to fork out extra for that when i still have a shiz load more other things to pay for. So just asking if i really need them. Looking at your responses some say no, some say yes, some say turn the boost down.