Are heads a tough job to install?

Your down that far, your not far at all. Just remove the pushrods and then the head bolts and they should come off. You will have to pull back the a/c bracket but I don't think A/C will need to be removed.

the compressor bracket bolts to the driverside head, you will need to purge all the refridgerant out before you take the heads off, it would be a bad idea to try to work around it, just recharge it with some Freeze 12 cans from the auto store, as long as it isnt R134. If you dont take the main upper line off of the compressor, you will have to pu**** out of the way several times to get that driverside head off, and you will risk breaking a line.

I don't think it's necessary to discharge the a/c system to swap the heads. Once the a/c and p/s brackets/mounting are unbolted from the head, you can simply ease the compressor and pump over to the side a bit with the hoses still hooked up. It's a little cramped - but it's much easier than discharging the system.

You will have to drain the coolant below head level - but if you've got the intake off already you probably have that covered. The toughest part in my opinion of a head swap with the motor in the car is cleaning all the gasket surfaces without getting a lot of crap into the engine, and getting good smooth torque pulls in the confines of the engine compartment. Just be patient and take your time.

What kind of heads will you go with?

Don't know what "crazy expensive" means - expense is relative to our pocketbooks, ya know? Anything aluminum, even used, is probably gonna set you back at least $800; probably more. The top line aluminum heads new are gonna be in the $1000-$1200 range. You could pick up some used GT40's or GT40P's (both iron) for much less than that; however, if they're used, I wouldn't put them on with out having a machine shop check out the springs, seals, and guides - a valve job wouldn't be a bad idea. Of course, those iron heads won't provide the gains that most of the aluminum heads will. Then Thumper and few others port the stock E7's and refresh springs/seals/guides with good results - but those will cost you too. So I'd say unless you have $500 to $1000 to spend on the heads/refreshing a used set, and the time to find them, buy them and have them checked out - then go on and put it back together.

I just did a head swap this summer, you don't have to do anything with the AC but be careful while you're working around it. Taking it off didn't justify the amount time it took to just work around it.

They haven't produced those heads new for some time. The GT40 heads last came new on Explorers and Mountaineers in 97; the GT40P's last came new on the 2000 model Explorers/Mountaineers. The P's never came on a Mustang new, and the last Stang version of the GT40's was the 95 Cobra. Not sure where your new sources are - I'd repost with a title like "Where can I get new GT40's or GT40P's?" By the way, the plug angle on the P's is different than on the 40's and it requires headers specifically designed for it. So if you go with P's, you'll need to replace your headers too. A used head with valve job, new seals and new guides is nothing to worry about. Done by a reputable machine shop, the rebuilt head will work just fine.

Been there and done that... 89roadster is right, you don't have to bleed the refrigerant out of the A/C. The compressor will swing back far enough out of the way without disconnecting any of the lines.

Plan on 3 days to do the job if you haven't done it before.

Day one gets the heads off in 4-6 hours.

Day two gets all the gasket surfaces scraped off extra clean and the heads dropped off at the machine shop if you are going to have them reconditioned. Time here is another 4-6 hours. Whatever you do, don't skimp on cleaning the gasket surfaces. New gaskets need to seat against bare metal and not the residue left from the old gaskets in order to seal leak free. This is the most time consuming and tiresome part of the job. Look for little things that need to be replaced like the short hose from the thermostat hosing to the water pump, damaged vacuum lines and hose clamps that are rusted or broken.

Day three starts when you get the heads back from the machine shop. This is the time to pick up all the little odd pieces you found needing replacement on your day two inspection/cleanup. Plan on 6-8 hours to reinstall the heads and reconnect everything. Plan on an additional 2 hours to troubleshoot/adjust everything.

Now for some practical tips:

You'll need new head bolts - get ARP bolts ($40) or studs ($93, maybe more). All the bolts get antiseize under the bolt heads, and everything but the short head bolts get it on the treads. You need Teflon pipe dope or ARP sealant to coat the threads of the short head bolts. The short bolts go into the water jacket and will seep coolant if you don't use the sealant.

My favorite trick that saves time and effort is the stay in place gasket. Be sure that you scrape (don't use a wire brush) all the old gasket material off, then clean all the surfaces with acetone or MEK.

When the surfaces are clean, use weather strip adhesive on the head to manifold surface, and on the side of the gasket that mates to the head. Follow the instructions on the tube or can and when it gets tacky, press the gasket down on the head.

Clean the area where the rubber rails mount to the block in front and in the rear with more acetone or MEK and do the same trick with the weather strip adhesive that you did to the heads.

Coat the rubber seals and the gasket area around the water passages with lots of Blue Silicone gasket sealer and put it together. Walla! No leaks and no gaskets that shifted out of place.

If you reuse the injectors from your old setup, a repair kit is available from most auto parts stores if needed. Coat the injector body "O" rings with oil before you use them and everything will slide back together.

Fuel injector seal kits with 2 O rings and a pintle cap (Borg-Warner P/N 274081) are available at Pep Boys auto parts. Cost is about $2.74 per kit. The pintle caps fit either injectors with a pin sticking out the injector end or 4 with more tiny holes in the injector end. The following are listed at the Borg-Warner site ( http://www.borg-warner.com ) as being resellers of Borg-Warner parts:

http://www.partsplus.com/ or http://www.autovalue.com/ or http://www.pepboys.com/ or http://www.federatedautoparts.com/

Most of the links above have store locators for find a store in your area.

For iron heads, clean the combustion chambers with a wire brush in an air or electric drill. I used a scraper for the pistons. I don't like to use the wire brush on pistons because it will remove metal very easily.

Plan on changing the oil once you get everything back together. Once the engine is up & running, run it for 1-2 hours and then change the oil. This gets all the loose carbon and gasket material down in the sump and away from the moving parts.

Tools: a good torque wrench is a must have item. A razor blade scraper that holds single edge razor blades from Home Depot or Ace hardware is another handy thing.

jrichker said:

Plan on 3 days to do the job if you haven't done it before.

Click to expand...

You forgot a day between 2 and 3...another day to lay on your back all day because it hurts like a B$tch from bending over the entire day before scraping and cleaning.

BTW Acetone works great for cleaning the gasket material off that the scraper doesn't get to.

Great tips from jr above - latham - unless your headers are P compatible, you'll have to pull your headers when you want to change the spark plugs. The FRPP headers were changed about a year ago so they work with the P heads too; if yours are older than that, you've got an issue to work out with the P heads. Also, if you have to have functioning emissions equipment, the P heads may or may not have the proper castings to supply exhaust to your egr system, and they may or may not be drilled to accept your air injection fittings. If you need that stuff, you better do a bunch of research to be certain they're gonna work for you.

In terms of alignment of components and gaskets, I bought several bolts of the same size, cut the heads off and slotted them so a flat blade screw driver will turn them. I use 4 of them (one in each corner) as temporary 'dowels' to position the lower intake gaskets - not only do they hold the gaskets, but they help postion the lower perfectly the first time. Once you've got a couple of other bolts started, remove the 4, and put the rest of your regular bolts in. Same approach works wonderfully on upper to lower, valve covers, and headers.

By the way - I searched the Year One site and couldn't find the P's anywhere. Probably just me....