"New" GT-40P heads purchased, what now?

I found some GT-40Ps off a 98 Explorer. Drove out to look at them, and I thought they looked pretty good. One broken bolt stuck in the hole, but I talked the guy down $25 because of it.

What next?

1) I will gasket-match the intake and exhaust ports, and smog bump, etc, just clean out the holes, and polish up the exhaust where I can reach.
2) Take them to the local machine shop, have them disassembled, cleaned, tested, seals replaced, replace any valves that might be bent.

Am I better off buying Hedman or Hookers that fit the stock heads, and having a muffler guy bend them to fit ($150 for headers, $100 for bend work), or just custom make a set ($500)?

Are these rockers any good? Keep them or replace with something else?

With my 8:1 compression, how will these help? Should I have the machine shop take off any from the bottom, and if so, how much?

Can I use my existing pushrods, bolts, etc?

Current cam is hydraulic flat tappet, 218/228 .050 duration, .471/.471 lift, kinda mild, I know.

Who all has these heads, and please, any suggestions to make this an easy swap.

Would cutting the shock towers be a good idea when I get the stock heads off?

Were these a good deal at $175 plus tax?

 

Are those non-adjustable rockers?

 

Just got home with them, haven't even looked. I will attach a pic and you might be able to tell me. I would assume they are non adjustable.

Scotty P, I may have already PMd you, but if you have GT40Ps, which headers do you use?

 

Those the the factory non-adjustable ...

 

I have done some research, and found that some guy named Mike Rude bought some Ford Powertrain Applications headers #943260GTP for his 1974 Comet. They never came back, but they also never got confirmation that they worked. FPA reported that the car IS on the road and running, but he is not 100% sure if he used those headers successfully. They were designed to fit older mustangs.

Mike, are you out there? Anybody know this guy?

 

No, I do not have gt heads.

 

To gasket-match, do I really grind my oval ports to a square hole, to match my gasket, or did they give me the wrong gasket?

 

That is what I figured.

So, did I ask too many questions for one thread??? Nobody has started to answer my questions

 

uh,, Scott,,, I think we are all cornfused. Man you got my brain workin. But dangit,, this is waaaaaaaaaay interesting. I am thinking get an oval gasket?
Dan

 

With my Gt40Ps I'm running regular 302 long tube headers and Accel "shorty" spark plugs w/90* electronic distributor cap boots on the plug end of the wires, 1.7:1 Crane Energizer roller rockers (exact same thing as Ford Racing "Cobra" rockers), the original length pushrods worked for me. These heads have 60 cc chambers so you'll have to calculate your CR. For iron heads on street engine 9.5:1 is about max with today's gasoline. Test fit the heads/headers/spark plugs on the bench first. you may have to grind the header flanges some to get clearence for a plug socket. You'll also be able to see if you need short plugs and, if so, how many. They aren't cheap, about $12 apiece at Summit. I only needed them for the drivers side but I put a full set in anyway. Almost forgot, max valve lift on P heads with stock springs is .500", which is ok because they don't flow much past that. They make a lot of low rpm torque which is what you want for a street engine.

 

Think you got the wrong gasket ..

 

60cc chambers won't hurt much if you try to get a thinner head gasket. Don't know where to get them, but I'm sure someone else does.
Should be a good upgrade, but it might be worth it to get a set of flat tops to go with it. With the slightly taller deck height, you still will only be about 8.8:1 comp ratio.

 

I'd suggest atleast getting a set of polilocks for your rocker arms.
Can set valves this way and frees up a lil horsepower.

 

If you want to go with polylocks you'll need to convert to screw in studs and guideplates and buy different rockers. I used the Crane kit and crane roller rockers on mine. then used the pushrods suggested by crane and all fit perfectly. but, with a roller cam. not sure about using them with a mild flat hydraulic. If it were me and I was gonna use these with the setup you already described, I'd port match the exhaust(careful it's easier to hit water than on older heads) use stock rockers and find the right length for pushrods and call it done.