So the spings could only handle a max of 480 lift if im correct then valve float would exist. E7 springs in gt40p heads.
351 Heads Worth It
E7 valve springs on gt40p heads. The valve springs recommended for that is the tf ford upgrade kit tfs 2500100 which has the springs keepers two sets of retainers one intake one exhaust theyre different shims and an installed height measuring device. 145 cc valve spring seat 90 lbs at 200 valve spring at 500 lift 310 lbs at 1500 valve spring coil bind 1300 retainer to seat contact 075 intake 077 exhaust. Either way upgrade is first thing that should be done. Instructions are also included. These kits include everything that you need to install a high performance cam. Find trick flow valve spring upgrade kits tfs 2500100 and get free shipping on orders over 99 at summit racing.
The keeper groove in the stock exhaust valve left is lower than with non rotator style valves because gt40p heads use shorter springs and a thicker retainer. The kits contain valve springs with dampers chromoly retainers valve seals locks spring shims and a spring height gauge. This kit was installed on my gt40p heads without any machining and is rated for a lift of 520 max. 86 302svo gt40 heads with 16 rockerse cammac long tubes and cat back bm blower670 holley elec pump mallory btm dizzy and msd coil 373 gears uplower arms with drag springs bag drive loop pro 50 shifter elec fan 195 stat bfg radials. From what im learning its a must to upgrade valve springs on the gt40p heads because the explorer engine has a low lift camshaft that was towing specific. 60 cc intake runner volume.
March 02 2011 112810 am no i used stock springs and rockers on e7 heads with an e cam and had no problems if you had problems if would be at high rpm not idle. Regular ford gt40 iron heads arent known for having the best valve springs either. I didnt use the tfs supplied valve stem seals after reading posts about them passing too much oil and guys then having to replace them. 184 intake 146 exhaust chamber volume. The above paragraph talks only about spring options for gt40p heads. Reply 4 on.
Keep in mind though that the cost of a spring package. I used the tfs 2500100 kit on my stock e7 headsgot a good deal from a local forum member. They are better than the stock gt40p springs but if pushing anything more than stock lift 0444 in it is best to replace them as well. Following information taken from carcraft magazine on gt40p heads. Gt40p heads upgraded valve springs.
Gallery of E7 Valve Springs On Gt40p Heads
