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One basic, step one thing when fitting new valve springs is checking installed height, pressure at seat and pressure at lift.

If these basic 101 things were done while the head was assembled, you should not have had a issue with valve float what so ever.

Shims can be added beween the head and spring, coil bind should have also been checked.

Cam makers give recomendations of these seat and lift specs.......

And get the instaled height and spring bind checked before starting the engine this time.

If the valvles are recessed from machining they will sit with too little pressure, shims need to be added under them to keep them within specs.

i know of a rb25 with performance springs and poncams made 580hp with manual and 520hp with auto, perfectly fine both around 25/26psi

I run a camtech 272 with lewis engines supplied springs and hydraulic lifters and they are fine at 24psi so far.

mind you i also had stock gear handling the power and boost also before cam upgrade.

hope this helps

  • 3 weeks later...

I have a similar setup as you have only im using a Wolf version 5 hypergear ss2 turbo and 660cc injectors and 98 pump fuel and getting 410hp at wheels with 15psi of boost when I go to high boost which is 19psi im getting 455hp at the wheels but I have std cams and my head was ported and flowed with heavier valve springs by Lewis Engines. I have a bit more lag than you but my tuner said it was to do with the slightly lower compression pistons 9.1.1 greddy manifold and the larger diameter primary tubes in the exhaust manifold but when the power comes on its a handfull. I wouldn't go heavier springs unless your going to go for solid lifters and cams as hydraulic setup doesn't really like too much valve spring tension you will wear out the top end of your motor. It might just be your tuner there are a lot of tuners out there that cant get the power out of a wolf computer.

  • 1 month later...

Hi guys

Thought you'd like to hear the results of the valve springs situation.

Changed out the performance springs for the supertech kit.

This was the only change and it went back on the dyno and the same place.

As you can see in the dyno graph the springs made a noticeable improvement.

Thanks to everyone for their input.post-12506-0-24816100-1427371399_thumb.jpg

  • 2 months later...

Hate to tell you but that statement makes absolutely no sense it's a spring for god sake it's there to control your valve shut it if it's the wrong tension spring select a better 1 it's that hard it's a spring

Edited by mr skidz

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