Beegle8950

I'm in the middle of an engine rebuild and I want to get new valve springs. I plan on buying a cam in a year or so. If I buy stiffer springs now, is there any way that it will hurt perfromance until I get a bigger cam? The rest of my engine is stock. Also, if I buy roller rockers in the future can I use the same springs? Thanks.

schwindty

Well if oyu think about it if the springs are more stiff in turn that makes them harder to open but easier to close, I would assume that it would eat some hp.... as for how much I have no idea thats something people dont run to the dyno and check. I would stick with the stockers for now and wait to get heads! PS dont buy a cam without doing heads! Buy some 1.7 RR's

grabbem88

if you are in the middle of a rebuild..why buy a cam a year later?..why not clean up your heads or get some gt-40
heads? you can pick some up probably cheaper than getting your stockers rebuilt/pollished.
on the rockers there is no issue there either...personally you need to think your rebuild through...poor choices
and wasting money is not the way to go...gaskets aren't that cheap doing multible teardowns.

schwindty

^^^ True dat^^ Gaskets are killer especially when you use the name brand ones!

Beegle8950

Well, here's the deal. My engine started knockning in the bottom end so I tore it down to find that the journal bearings were badly worn. I have almost no extra $$ to spend cause I'm workin my way through college right now, but of course I have to get my stang back on the road. I was planning on just cleaning up the heads and new springs for the top end. You're right, I should save myself from another teardown, but one new part continually leads to another and I have to draw the line somewhere, I'm just not sure where yet.

grabbem88

LOL...not directed to you,but yes one thing after another.
it is never ending when it comes to modding...if you draw a line like i did..it will just get longer,and longer.

89 mustang

"If I buy stiffer springs now, is there any way that it will hurt perfromance until I get a bigger cam?' NO. It will actually help you give more power,this is the deal,the stock springs give up at 5000rpms after that it is all valve float because of the springs cant bring the valve back in time.Up grading you springs will give you like 1500rpms more. This is good now your pony has power up to 6500rpms.

Beegle8950

6500 even with the stock cam and rockers?

grabbem88

stock cam will be way done before 6500...besides the 3/8 rocker bolts won't handle that much stress. let alone the harmonics.

Twister

stiff springs push the lifter's plunger down, especially when first moving the valve off the seat at higher rpms. Then, as the lifter passes over the nose of the cam and starts moving back down the ramp, clearance is created at the plunger without any load on it. This clearance is quickly taken up with hydraulic pressure from the oil pump, which holds the valves off their seats and kills power at high rpm. This problem is even worse when you increase the rocker arm ratio. Unfortunately, once this occurs, the valve springs begin to deteriorate quickly as well, and the more you try to rev the engine, the worse the problem gets.