Valve Springs upgrade question..

[heshan]

Hi guys,

I'm doing a 4AGZE conversion and I'm also upgrading the Inlet Valve Springs to an after market set..

two questions;

1. I'm only upgrading the Inlet ones so would this actually give me power? (it would as per my mechanic)

2. What sort of advantage would I get by going these high tension springs?


I'm jsut want a 3rd party opinion...

THanks,
Heshan.

[PatrickAE86]

only spring upgrade won't make much power gain...
but with agressive cams and high rpm they are a must have
becouse oem once are to slow and wil brake...

[heshan]

Thank Patrick..

Woud I still gain a bit with just the Inlet side being upgraded?

[jondee86]

Sorry dude, but changing valve springs won't make the slightest bit of
difference on an engine that is running stock cams and ECU. You only
need them if you are going to have more lift than the stock springs can
handle (i.e. spring binding problem), or expect to see rpm's higher than
the stock redline (i.e. valve float problem).

Cheers... jondee86

[SekiguchiUeno]

you only gain some parasitic drag and camgear wear if you want to use stock cams.

My question is what for springs to use for cams with slightly higher lift (1mm) are the TRD/HKS.... cams not too stiff? Its enought to buy only new stock springs? Catcams, kelford recomend stock springs for the stage1,2 cams.

[Bean]

SekiguchiUeno Wrote:you only gain some parasitic drag and camgear wear if you want to use stock cams.

My question is what for springs to use for cams with slightly higher lift (1mm) are the TRD/HKS.... cams not too stiff? Its enought to buy only new stock springs? Catcams, kelford recomend stock springs for the stage1,2 cams.

OEM spring have there limit@ about 9mm (some say 8.5) but personaly I wouldn't trust 25year old springs being at their limit on a performance engine... the HKS will deal with 9mm easily and wont be overkill (HKS cams are less than 8.5 anyway)

[heshan]

hey guys.. thanks for the input..

I spoke with my mechanic and he disagrees that there will be camgear wear..

He says that there will ONLY be improvement in the manner in which the engine will revv after 5k RPM.. Is this true?

[Bean]

heshan Wrote:He says that there will ONLY be improvement in the manner in which the engine will revv after 5k RPM.. Is this true?

this would only be true if your current OEM springs are realy shagged - OEM springs in a good state can handle high revs all day long without a need to wory about valvebouncing as long as cams are OEM or only a slight tune (8.5mm the safe limit IMHO for used springs)

[heshan]

based on my mechanic once i add the new springs the engine will Revv much faster than stock after 5k...

Not sure if its true or not... its tooo late for me now.. i'll have to live with the springs.. so i'll let you guys know whether its true or not..

also anybody done the FMIC for the 4AGZE? got pics?

[robokill]

fmic is standard upgrade on a 4agze. just make sure you do the piping correctly. Always make the shortest and "coldest"route

Fresh springs are never bad. But you won't notice it in the engine. Like we say:

it will be between your ears.