I may go the GT head route if I can get them cheap enough, but I think that might get almost as expensive as new heads. If I can get a pair for $200, I'd then want to send them to be checked out at a machine shop and have new springs installed. That could easily run another $200-250 per head, maybe more because I haven't really priced it. I could be $6-700 into a set of heads and it looks like I could get much better performing aftermarket heads for only a few hundred more. Granted, that would mean a new fuel system but if I'm going to pull the heads I guess a new FPR and injectors wouldn't be that much more work.

I cant tell you guys how much I appreciate the input. You've saved me from probably making some expensive mistakes.

 

Keep an eye out on Craigslist for a set of used aftermarket heads and even a set of out-of-the machine shop gt40s.

A shop won't charge you much to check the valves and deck if needed....this would be the jy route. Springs aren't really expensive either. I got my afr's off Craigs for 1000 with 1.7 rockers, decked them for compression and bolted them right up.

 

Pulled junkyard gt40p heads for $30 but not sure if they're any good so I went back for the other set and pulled them for $30 as well. More off the knuckles than out of pocket, but if they're all good, two will make they're way to Craigslist and a new home for a considerable return.

 

Ahhhhh the benefits of you-pick-you pull. So cheap, it doesn't matter if they're good or not. But they are a bitch to pull!

"Worth every second", vs "worth every penny".

 

Well, every penny is $300 for P's or $400(pretty sure) for GT40 from a friend with dozens of each in stock. He ships as well, if anyone is interested.

And every second was kind of a thrill, fighting the clock, the rusty manifolds, the steering shaft, the heater box, the accessories, fighting FOR traction... All with a decent selection of hand tools but not exactly the right ones. Tough to drag the roll away through the mud and snow at the u-pull haha. I would guess I have 8 hours in pulling both sets.

But very true. They're still unknown and I will get them checked out before hand. I think I read the P heads require an upgraded valve spring. If so, and if I were spending $300 for P heads, I would just spend the $400 on the 3 bars.

 

I've been able to run every set of gt40ps I've gotten from the jy over the years, probably a half a dozen sets, with no valve job if that makes you feel any better. Makes it worth the pull.

 

Well I spent all morning out at the junkyard and picked up a few things. Most notably I got a 5.0 upper intake and an extra 5.8 lower along with a set of GT40P heads out of a 98 Exploder. I'll get them checked out by a machine shop, not sure if I want to run them or sell them and put that toward some AFR or TFS heads and a fuel system. Lots of 460 trucks out there that I could pull a computer out of. That might be a better option than trying to get headers and plug wires that will work well with the P heads. We'll see what the machine shop has to say about them and I'll go from there. I didn't get them as cheap as some other folks have but it wasn't too bad.

 

You don't need special plugs/wires or headers for gt40ps in trucks, as long as you use long tubes.

The fitment problems associated with the p heads are generally for mustangs or for those who use shorty headers in their trucks instead of long tubes.

 

I'm getting ready to pull the trigger on a set of Flowtech 12504FLT headers this afternoon, then I will build my own 2.5" exhaust off of that with premade mandrel bends and a good muffler. I need to address this first because I do have an exhaust leak. It looks like I'll have to add an EGR bung to the passenger's side header, anything else I need to be aware of?

How about mufflers and resonators? I don't want to sacrifice power, but I do want to keep it quiet in the cab. Will I see any negative performance effects from having both, or should I just stick with one muffler and no resonator?

 

If you're 4x4, be prepared to bend the drivers collector in toward the Trans to clear front driveshaft. Not a big deal, just need a torch, and you may not have to bend it at all.

MagnaFlow muffler should do the job just fine.

 

Looking forward to pics of the exhaust after the headers. I can probably do the install at a friend's place, with a welder. And I'd rather not pay someone to do it if I can do it myself. But if it's a big pain in the butt, it might be worth having someone bend me a y pipe that I can add the rest to with clamps. Right now I just have a magnaflow bolted on after the cat, and a 90 coming off of that pointed at the passenger side. I will probably do something similar after a y pipe and no cat.

 

Oh and the magnaflow isn't louder than the steering pump, or injectors. You can tell its back there, but definitely not loud or obtrusive. I imagine it will be louder with headers and no cat, but it seems like the right choice for what you're after.

 

Any particular Magnaflow you recommend? I found the 12368, does it seem like what I'm after? Likewise, is there any reason that a separate Y pipe is better than a two in, one out muffler?

 

Good question. Was thinking that myself recently. If you can get the two pipes coming off the headers close enough, why not just use a muffler like you described as the y? Sure could make things easier.

 

The 12368 specifies that it can be mounted either direction, but I don't know if a smooth transition in a Y pipe will be better for flow or scavenging than what might be a more turbulent transition inside the muffler.