E7 Head questions

[SirFoxx]

Look at what I picked up this weekend!








I have a few questions--since these heads are used, should I take them to a shop and make sure the head surfaces are true? They came off a good running gt motor supposedly.

When I do the swap, should I replace the RR's or the push rods?

Is there anything special I need to take account for when installing the exhaust manifolds? They're from a '90 TC.

This question is a bit off topic--whenever I'm at a light, and step on the gas, there is a hesitation before the engine starts accelerating--what could be causing this?

[sly]

unknown heads should always be checked unless you are doing a Roadkill build and don't care about blowing out head gaskets 10 miles down the road.

The rest of the parts... only if they are out of spec (re: bent) or you're changing something in the train.

The exhaust should match up on every 5.0L panther no issue.

[sly]

This question is a bit off topic--whenever I'm at a light, and step on the gas, there is a hesitation before the engine starts accelerating--what could be causing this?

This one has troubled folks for eons. Some have found TPS issues... some have found timing, spark wires, plugs, MAP sensor, air charge temp sensor, engine coolant temp sensor, and other issues. It could be timing chain slop. There's no end of what's been found to cause that hesitation. Most people just deal with it. I know that's the case with me.

[gadget73]

Honestly, I'd skip them entirely and get some Explorer heads. They're by far a better cylinder head. If you're spending time and money on stock castings, you may as well get the best ones available.

If you're gonna use these, have them rebuilt. New valve guides, new seals, replacement valves as needed, grinding and lapping the seats, and resurfacing them as needed. New valve springs depending on the cam. Stock ones are only good for so much lift and so many RPM. Not sure precisely what that number is, but if you tell the engine shop what cam it is and how fast you want to spin, they can tell you if the springs will do it or what you need if they won't do it.

[knucklehead0202]

E7's are better than E6's but that's about all there is to say about them. If you got 'em cheap or free it might be worth the effort to stick them on but i'd hold out for something better. If you've got the time and initiative it's a decent improvement, but i'd rather do it once and put something awesome on there. The Lincoln logs should be a simple swap. Far as hesitation goes, well, like the others said, it's kind of a fact of life really, unless you get lucky and accidentally change the thing that's causing it. Finding it can be a riddle.

[nfldfordltd]

Lincoln logs are a direct bolt-on replacement, no mods necessary. I took the opportunity to replace my O2 sensors when I installed the logs, everything worked beautifully after I got the old manifolds off.

[SirFoxx]

Well I got the heads for $50...Should I have them checked out and the air tube ground down in the exhaust port, or should I sell these and get a set of GT40 heads? I know this is a very opinionated question, but I would like to get as much out of the motor without swapping the cam and computer...for now. I already have these heads, and I'm not sure if I can conjure enough motivation to go to a pick-n-pull and hunch over an explorer and remove a set of heads that may or may not need a complete overhaul.

As for the lincoln logs, what kind of performance increase should I be expecting...?

Also, MAP vs. Speed Density, will I need to worry about this only after I swap a cam and computer into my car?

[merc91]

Definitely go gt40/p heads. It's not even worth the work and price of gaskets to put on a free set of e7 heads never mind spending the $$ on them to freshen up. Unless you want to try experimenting with a cheep head with lots of wall material for porting. They can match stock gt40's when ported well. Again not worth it unless that porting stuff floats your boat like me lol.