Buying Heads, Checking Ptv N Pushrod Length For The Non Diy Guy?

90lxwhite

I'm kind of a She-Man
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Aug 25, 2011
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Ok so I'm in search of some heads for a 95 gt (prob used, shucks) but anyway here's the issues I'm wondering about: I realize its recommended to clay up and check ptv clearance before install. So what, does a guy take a gamble and order set, take them to a mechanic "clay them up" and hope there's no issues? Another question/concern I have is with selecting the correct pushrods. So what am I supposed to do go to a shop have em tear the motor down measure for length and leave it sitting in the shop torn apart until the correct pushrods come in from the interweb? Isn't there a set of heads out there that will bolt on and go? I'm looking to replace a fresh set of e7's that are on a fresh bottom end. I'd like to reuse my rockers if possible. Im using a .512 lift cam with 281 duration. Man, this is turning into a headache, I can see labor cost going through the roof. Below are my cam and piston specs:
2000 to 5500 operating range
35-440-8 part number
281HR cam grind number
281 duration in (advertised)
281 duration ex (advertised)
220 duration in @ .050
220 duration ex @ .050
.
512 valve lift in
512 valve lift ex
110* lobe sep angle
Product Line: Speed-Pro Hypereutectic Pistons
Summit Racing Part Number: SLP-H120CP30
UPC: 614046226869
Bore (in): 4.030 in.
Bore (mm): 102.362mm
Piston Style: Flat top, with two valve reliefs
Piston Material: Hypereutectic aluminum
Compression Distance (in): 1.615 in.
Piston Head Volume (cc): +5.00cc
Wrist Pin Style: Press-fit or floating
Pin Diameter (in): 0.912 in.
Piston Ring Thickness: 1/16 in. x 1/16 in. x 3/16 in.
 
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You bolt down the heads, use a pushrod length tool then order. I'm lucky, manley is near by so for me they are quick and easy.

There are pedestal mount rockers and stud mount rockers.
Stock heads are pedestal, most good aftermarket heads are stud mount.

You don't say what rockers but if they are stock rockers, do not reuse them.

That cam doesn't seem too wild, but i'm no cam expert.
 
We measure and order pushrods for customers cars every day. It's usually only a day to get the proper push rods and there is always more than one project going on at a time. Let the shop check ptv clearance and make sure you ask what it is when said and done. Labor costs should be reasonable so don't sweat it. This is a rudimentary job on a mustang. As far as rockers, you likely have pedestal rockers and will want to go with a set of stud mount rockers.
 
you get the heads first, then match the cam and springs to the heads, not get the cam and then match the heads to the cam. That being said. you should clay up the heads with any non stock setup. However, not everyone does and frankly there are thousands of guys that run either TW, AFR 165, Edelbrock Performers, etc. with no problems. If you are buying any used head, then hell yes you better mock them up first, as they could have been milled. There are many factors involved with PTV like deck height, gasket thickness, head height, pushrod length, cam duration, piston height, rod length, and other variables.

Measuring for proper pushrod length isn't hard. Do a google search and there are tons of videos. Most of the head manifactures have known lengths for different combos but again you should always measure, especially with used heads, not only for PTV but also to make sure you have proper geometry and swipe on the valve tip.
 
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