mcget29

I have trickflow twisted wedge heads, they came with these http://www.summitracing.com/parts/TFS-51400413-1/.. there supposed to hold up to mild cams and even boost, however, i only have a 306 with an E cam and some forged pistons...

Now about 3 months ago i broke my first spring.. thought it was only gonna be a one time thing so i replaced it with a single i ordered from summit, 2 months later another spring broke so i did the same thing and replaced it.. now about 2 hours ago another one broke but this one was on the other side of the motor..

What could cause this? is it that the heads are kind of old (from 2003) so that their fatigued?
Or is it a loose rocker that could cause this because most of the rockers with the broken springs were loose..

Any help would be great!!

mattdel

bad batch, wrong spring... something. i'd replace them all.

Tony71502

Umm when you break a spring, there is no pressure against the rocker. Obviously it will be loose.

There's really no such thing as a fatigued head. The springs are not installed properly or have the wrong spring pressure to work with your valve train.

mcget29

i meant fatigued springs.. these heads were put on in 2003 and i have never changed the valve springs that came with the heads.. the car is raced frequently too..

Tony71502

Cars with valve springs from 70s, 80s, 90s get heavily abused on stock parts.... you don't hear about them breaking...

mjr46

they are not running performance parts/cams either for the most part.....OP YOU'D BE WISE TO REPLACE ALL THE SPRINGS, AND when setting them up check the geometry and make sure push rod length is correct but more so check for coil bind and make sure the seat pressure is adequate

94StinkinLincoln

Take some pictures of the springs, pushrods, rockers, and studs.
Use the macro function one the camera also.

mcget29

These heads are trickflow heads that came with the springs rockers and pushrods allready assembled, so i'd hope that trickflow wouldnt give me pushrods that are the wrong length u know.. .. The car makes 292rwhp 311tq running an E cam, many cars from the 70's and 80's with stock parts dont come close to that, if was running under 200hp i wouldnt worry about a spring breaking.. but still these heads should easily handle that power.. thats why i was wondering if anyone had a possible explanation.. my only guess is to lower the rev limiter, its currently at 6000, and im definatly replacing all the springs

94StinkinLincoln

Grasshopper, you have MUCH to learn.
EACH, not some, EACH motor will require a different length pushrod.
Intake valve can require one length and the exhaust can require another.
A few things thats play into pushrod length:
Head deck height, block deck height, valve length, rocker used, lifter used, cam used. it all plays a part in the length.

the spring does not care if its on a 10hp motor or a 1000hp motor with the same cam and rpm. the spring controls the open and close of the valve and the harmonics that are given off.
The harsher the lobe (the faster it opens and closes and consideration of lift; the COMBINED specs of the WHOLE lobe) the better the spring will need to be. The heavier the valve, the better the spring you will need.
More rpm needs a better spring.

This whole "subject" might be a little bit deeper than you originally thought. I am by no means an expert, so take what i say for its value; Free.
Now go and research and learn some more. A custom cam grinder would be your best bet to seek advise from, but do not be surprised; the best route is not always the cheaper route.

93 LX FiveO

the heads came with pushrods already installed? wow... and 291 is not impressive rwhp