Valve Float / Valve Spring Question

[MeanGreen]

So after adjusting my timing and Fuel Pressure it looks like the problem is Valve Float because its still hitting the Rev Limiter to early (5300 RPMS). I am just gonna do a Valve Spring/Retainer upgrade.
Currently am running the Valve Springs that came with the Edelbrock Perf. Heads. There just not cutting it for the E-303 and 1.7 Roller Rockers I guess
What do you guys think would be a good upgrade to this to get rid of the Valve Float? Something to handle up to .600 lift? Right now I am around .529 lift with my setup.

 

[Kdubslugga]

Im glad you posted this cause i have the same problem, mines at 5600 though, i have stock heads on there still, i would have thought that the performers could handle that lift!, whats an e cam .498 plus the .030 from the rockers soooo, .528 total lift, yeah get some that can handle up to .600 should never even be close to that

 

[MeanGreen]

Yeah I don't mind upgrading the Springs/Retainers as I have the tool for it to make it easier to swap out. I just wanted to know of some good brands some of you fellas might be running and had good expierences with.

Your stock heads probably most def could use them! I am pissed that the Springs that came with the Edelbrock's are takin a dump on me though

 

[vristang]

So after adjusting my timing and Fuel Pressure it looks like the problem is Valve Float because its still hitting the Rev Limiter to early (5300 RPMS).

I'm not sure I fully understand...

How would valve float cause the rev limiter (controlled by the ecu) to activate early?



jason

 

[Mustang78]

maybe it floats and just craps out..i would also like to hear some good spring recommendations, i've heard nothing but good about beehive springs, except you ned the 70.00 special retainers to go with them

~Mark~

 

[kilby94]

I'm not sure I fully understand...

How would valve float cause the rev limiter (controlled by the ecu) to activate early?



jason

I think he just means the motor is acting like it hit a rev limiter.

I am going through the exact same problem right now in my 91 5.0 won't rev past 5,000 with the e-cam and a set of 351w heads. I am ordering the trick flow kit from summit. It is good for a .542 lift cam, and has close to 300 lbs open pressure. It is $135 for the whole kit. Springs, keepers, shims, retainers, and i think valve stem seals.

 

[85_SS_302_Coupe]

Are you guys having these issues because of the aftermarket cams you're using? My car is still on the stock heads and cam and it'll literally rev as high as i have the guts to rev it since i'm not running the stock ignition and i don't have a rev limitor. It'll run clear to 6500 either in neutral or in gear, and everything is stock as far as the valvetrain goes.

 

[jtfairlane]

One thing that no one has mentioned is lifter preload.

When people do a poor job of installing a hydraulic cam (flat or roller, same principle) and don't ensure that they have proper lifter preload, and if they end up with excessive lifter preload (say greater than .060"), they can develop the same symptom (motor being unable to rev past a certain rpm, feels like a de-facto rev limiter).

Something to consider before spending a bunch of money on a valve spring upgrade.

 

[kilby94]

How do you go about checking lifter preload?

 

[goodfastncheap]

To check lifter preload, with the valves closed, back off your rocker adj. nut until you can just spin the pushrod - that would be zero preload. Studs are 20tpi, so tighten 1/2 to 3/4 turn for .030" preload. Rotate the motor by hand to the next cyl. and repeat.

I would check this for sure before you assume bad valve springs. Also run good clean low-viscosity oil at the proper pressure.

 

[Fox8950]

http://www.cranecams.com/pdf/453e.pdf has a pretty good method of getting the correct preload .. has always worked for me anyways and is easy to understand.

 

[thumper460]

Change the springs and retainers... the Brocks have had issues with their springs.. Great heads, just spring issues.

I have some drop in dual springs for your heads that will work great for the cam and 1.7's, and they will carry bigger lifts up to .600 if you decide to go bigger later... cool??

Just me..................................

Thumper

 

[PUNISHER RACING]

same here 85...... X cam and stock heads I have rev. set to 7,000 every time I shift its at 6,800

 

[Distortion 5.0]

same here 85...... X cam and stock heads I have rev. set to 7,000 every time I shift its at 6,800

Christ I bet that sounds mean as hell! I've never heard a 5.0 rev past 5.5k that I can remember. In fact I doubt the one I'm working on now has been past 5k in it's life.

 

[85_SS_302_Coupe]

Christ I bet that sounds mean as hell! I've never heard a 5.0 rev past 5.5k that I can remember. In fact I doubt the one I'm working on now has been past 5k in it's life.

Here's a really old clip of my car at about 6k...


View attachment 342865

 

[BYRDPE]

How are you guys reving past 6250?

 

[85_SS_302_Coupe]

How are you guys reving past 6250?

I'm running a Malory Comp 9000 distributor with its own ignition module, and i'm not running any rev limiter. It'll rev until it pukes

 

[PUNISHER RACING]

Carbed!

 

[85_SS_302_Coupe]

Carbed!

That too


I like to control my own rev limits. If the throttle sticks then you should've added a double spring on the throttle linkage