valve springs

[joey74]

I'm going to take my gt40p heads apart to put new valve seals would hurt to upgrade the springs as I'm still running the stock camshaft?

 

[scotts90ranger]

Won't hurt anything but won't gain anything unless you are running higher than 5000rpm like the stock Explorer tune. I put the fancy trick flow springs in preemptively since I'm likely going to get a tuner...

 

[alwaysFlOoReD]

Take your springs to a machine shop to get tested. Then decide.

 

[85_Ranger4x4]

Trick flow has a nice kit that is a better than stock but not crazy stiff though either.

 

[joey74]

Take your springs to a machine shop to get tested. Then decide.

well in the future I'm going to put a mild cam if anyone could tell me what size.

 

[scotts90ranger]

I put in a mild cam too, the cam doesn't matter, it's all about the rev limit. More rpm means the springs have to fight the inertia of the valves more, the explorer heads have super light valve springs but they hold fine for the 5000rpm rev limit, at 250k miles my engine had worn out rings and bearings but the valves just needed touched up and the seats were just fine which is what the light springs are about... I plan to run more rpm so I put in heavier springs...

 

[joey74]

I put in a mild cam too, the cam doesn't matter, it's all about the rev limit. More rpm means the springs have to fight the inertia of the valves more, the explorer heads have super light valve springs but they hold fine for the 5000rpm rev limit, at 250k miles my engine had worn out rings and bearings but the valves just needed touched up and the seats were just fine which is what the light springs are about... I plan to run more rpm so I put in heavier springs...

what cam did you go with and do you have a parts number?

 

[joey74]

Trick flow has a nice kit that is a better than stock but not crazy stiff though either.

would you have a parts number?

 

[scotts90ranger]

I used COMP Cams 35-349-8

I'm pretty sure THIS is the valve spring kit, I know it's the one I used.

 

[Bigmatthew86]

Alex parts makes good drop in kits too. Tell him what cam you plan to run & he’ll tell you what springs.

 

[JoshT]

If you are removing them, replace them. The Explorer valve springs were underperformers and weak from day one. They served Ford's intended purpose for the engine, but only barely. Yours have 20+ years on them at this point, and they don't get better with age. Replacing them will even help the stock cam get a little higher in the RPM range before floating, basically a must if you upgrade to anything else.

I'll second Bigmatthew86's recommendation. My springs came from Alex's Parts many years ago. They no longer offer the kit I bought, or I'd share the P/N. Contact them with whast you have and your plans, they'll recommend which springs to get.

I haven't used the Trick Flow kit, but it seems to have good reviews as well when used as a replacement for stock application. If upgrading the cam at the same time, get what ever the camshaft or maker calls for and recommends.

 

[Bigmatthew86]

Are you using a v6 or v8 explorer engine?

 

[Bigmatthew86]

I thought we were talking about a 5.0 swap. Can’t help you on the 4.0

 

[JoshT]

I think that there might be something about head differences in one of the 4.0L tech library articles.

Functionally you should be able to use either head no problem, but I probably wouldn't mix them side to side. Generally speaking, the later model casting should be the better casting. It might have less wear too.

I thought we were talking about a 5.0 swap. Can’t help you on the 4.0

Yeah, I was wonering why he posted that in here myself. Josh has been around long enough to know better, but could have though he was replying to a different thread.

What say ye @Josh B, did you make a mistake or we we need to put you in timeout for thread jacking?

 

[Josh B]

I thought we were talking about a 5.0 swap. Can’t help you on the 4.0

Yeah, that;s cool