1998 5.0 V8 Explorer Phase 1 Build...

[rocket 5979]

If I am not mistaken some of the Motorsport head can be had for around a grand.

Yeah, you are right. There are some other options available out there in the price range. The problem with that is that those options available may spec well for flow, but they sometimes end up not producing the type of power wanted in a vehicle of this weight. I have really gotten back to my 5.0 roots that I started out with on this board over 7 years ago. I knocked the rust and cobwebs off of those memories in my brain that had been hidden for a while because I have not used it.

The call between worked GT-40P heads and some of the cheaper aftermarket ones is a tough call. Allot tougher than allot of you may think actually. The P heads in ported form have pumped out 300+ rwhp with basic boltons and with a mildly aggressive cam in more than a few vehicles. Of course, so have other head combos too. The difference is that the P heads usually made more torque, and with the meat of the powerband lower in the rev range too. That is something that is critical for these Explorers obviously.

In the next few days I am betting that Jim will have made his mind up by then. When that happens this thread will be updated to reflect that.

Overall this is shaping up to be an enjoyable project so far, despite Jim leaving 2 foot puddles of oil on my floor.

 

[Jimbo1221]

Yeah, you are right. There are some other options available out there in the price range. The problem with that is that those options available may spec well for flow, but they sometimes end up not producing the type of power wanted in a vehicle of this weight. I have really gotten back to my 5.0 roots that I started out with on this board over 7 years ago. I knocked the rust and cobwebs off of those memories in my brain that had been hidden for a while because I have not used it.

The call between worked GT-40P heads and some of the cheaper aftermarket ones is a tough call. Allot tougher than allot of you may think actually. The P heads in ported form have pumped out 300+ rwhp with basic boltons and with a mildly aggressive cam in more than a few vehicles. Of course, so have other head combos too. The difference is that the P heads usually made more torque, and with the meat of the powerband lower in the rev range too. That is something that is critical for these Explorers obviously.

In the next few days I am betting that Jim will have made his mind up by then. When that happens this thread will be updated to reflect that.

Overall this is shaping up to be an enjoyable project so far, despite Jim leaving 2 foot puddles of oil on my floor.

What oil? I want visible picture proof!

I don't know about the heads, I am playing it by ear until I get my estimate. So if you see me post some 4,500 dollar heads, I am just bored at work jacking around. As far as progress on the truck goes, I am relaxing from a retarded day at work. So no progress.

 

[tmsoko]

I have to say, bang for the buck, box stock TFS Twisted Wedge heads are VERY hard to beat.

 

[rocket 5979]

I have to say, bang for the buck, box stock TFS Twisted Wedge heads are VERY hard to beat.

If you are going for bigger power then maybe... For this application they are not optimal from more than one standpoint.

They are good heads but there are way to many people that really have no clue as to the P's potential in worked form. For a torquey head they are hard to beat, bang for the buck. They can be worked to give ONE HELL of allot more power/tq under the curve, not just at peak. The great thing is that peak flow will not suffer due to the gains made under the curve too. That under the curve gain is what really matters most, especially when in a vehicle like this.

By far the largest amount of accelleration in a 1/4 mile race is done in the first 60', which is why it is sooo very important to get the holeshot. Though vehicles obviously are still accellerating in the second half of the 1/4 mile, it is still nothing when compared to the accelleration that is happening at first. In the first section of the race, especially off the launch you need allot of torque and power to get out of the hole. When looking at the ratio of pure accelleration vs elapsed time the nod goes to the first few hundred feet of the track. That states something VERY critical, which is that vehicles need a good launch to set the base for a good 1/4 mile run. There are exceptions to this of course (turbo 4 bangers and some others) but what I said still applies to the wider selection of vehicles on the track these days.

Now I know that you know this, and allot of other folks who race know this too. It is still smart to also keep this mind when coming up with a combo to match the requirements of the vehicle best. All out superflowing heads do not neccessarily equate to better 1/4 ET's, and the extra money spent to get those can be put to better use elsewhere on the vehicle.

 

[CDW6212R]

Those Pro Comp 175cc heads that I'm thinking of would be best to have a machinist verify the valve job(look them over). Thus with shipping I see $850ish and maybe as much as $950 after local work.

You can use your stock rockers with the stock GT40P heads, as well as the pushrods. I would rather use stock rockers for a budget build, aftermarket heads can often require different rockers and pushrods.

 

[rocket 5979]

Those Pro Comp 175cc heads that I'm thinking of would be best to have a machinist verify the valve job(look them over). Thus with shipping I see $850ish and maybe as much as $950 after local work.

You can use your stock rockers with the stock GT40P heads, as well as the pushrods. I would rather use stock rockers for a budget build, aftermarket heads can often require different rockers and pushrods.

What are all the specs on those heads Don? Will those heads be the ones that you will also use later when supercharging? Only reason I inquire is because I am curious the CR you plan to run; which will influence what combustion chamber size is used.

 

[CDW6212R]

Just about all of the variants of their smallblock heads have 60cc chambers, the high end 225cc port versions are 64cc chambered.

I'm actually just about conceding that I will buy two pairs of heads. I need to use a head for my baseline engine which has the exhaust port flange that I will make headers for. Then I can add the supercharger after the headers.

I would much rather prefer to build headers before a final engine swap, so that the important engine only needs tuning. I guess the best head then is a basic stock application choice. I think that the Pro Comp heads have normal ports, just 1/4" higher. I'd resell the first heads later.

 

[CDW6212R]

I'll want about 9:1 with both engines for supercharging. Building a 331 or 347 will likely require some kind of piston dish.

 

[reserved50]

Only problem is if you get the Powerdyne kit, since I have not found any 50oz imbalance stroker kits, they give you a 50oz balancer and the machine shop that did my engine did not want to drill the PD balancer due to it being cast. I went with the Probe/Scat 331 kit with mid 8 to 1 dished forged pistons and thicker Cometic headgaskets

 

[rocket 5979]

Only problem is if you get the Powerdyne kit, since I have not found any 50oz imbalance stroker kits, they give you a 50oz balancer and the machine shop that did my engine did not want to drill the PD balancer due to it being cast. I went with the Probe/Scat 331 kit with mid 8 to 1 dished forged pistons and thicker Cometic headgaskets

I don't think he is planning on going with a Powerdyne.

 

[jah81592]

Rocket,
I completely agree with you on the P heads and torque. Most of the 5.0L heads are geared toward hp (light fox chassis) while sacrificing torque which the Explorer needs desperately. There is a mild aluminum Motorsport head I cant remember which one (part#) it is but they usually don't make the same hp #'s as AFR, Trick Flow,etc but they are designed with a well round hp and torque package which was my reasoning for the recommendation. I will have to dig and see it they are even available anymore.

 

[CDW6212R]

All of the smallest heads by all companies are basically aimed at stock 302's, and the stock rpm ranges. There are actually dozens of choices now, so only generalities are appropriate. None of the Ford heads are appropriate for real race engines, big displacement and supercharging. Ford has always been infantile in it's choice of customer bases. All of their heads, even 99% of the Motorsports stuff, they have very poor exhaust ports and flow. The aftermarket heads are hampered by the Ford exhaust designs(dimensions), thus they are not optimized.

I like Ford products for their quality, but many designs are very poor, flawed, or deficient(less than ideal). Case in point, the 4.6 DOHC engine should never have made less than 300-325hp, and the latest should be around 450hp(1hp/liter).

To the point about heads, this project truck is about a slightly above stock 302 engine. Nothing should be considered for heads that would cost $1000 or more. That eliminates most of the head choices, and leaves just the basic versions of each manufacturer. We would all love to have light aluminum heads, and many can be had for well under $1000.

From what I've heard of this project, like all projects, either a basic head choice should do fine(rebuild the stock heads), or step up slightly to the next level. I'd either limit costs by spending only a couple hundred on rebuilding the heads, or buy a basic aluminum head and have a machine shop go through them for flaws.

New or used basic aluminum heads have a good 40-50hp more potential in them than the stock GT40P's. Those basic heads should all test to be within about 20lbs.ft. of torque of each other at all under 4000rpm's. Those differences are not enough to justify spending an extra $800 or more. As Rob would agree, spend a bunch of time and thought on realistic goals, and plan carefully for them. Jim's in good hands, congratulations in advance on the finished project. Regards,

 

[rocket 5979]

Rocket,
I completely agree with you on the P heads and torque. Most of the 5.0L heads are geared toward hp (light fox chassis) while sacrificing torque which the Explorer needs desperately. There is a mild aluminum Motorsport head I cant remember which one (part#) it is but they usually don't make the same hp #'s as AFR, Trick Flow,etc but they are designed with a well round hp and torque package which was my reasoning for the recommendation. I will have to dig and see it they are even available anymore.

Sounds good.

 

[rocket 5979]

Got a late start today but we were able to pull the heads, cam, and exhaust manifolds off today. Talk about some nasty stuff inside those heads and on the manifolds. I am glad that it is all rebuild from here. Sometimes it gets old trying to remember which bolts have to come out before getting a part or piece off.

Now the heads can be sent off to be worked. After that is done then the fun part begins which is putting it all back together.

 

[410Fortune]

Looks familiar! LOL

 

[rocket 5979]

Waiting on my buddy Jim to get off his lazy butt so we can order the rest of the parts, clean this stock shortblock up real nice and then start putting it all back together. Jim decided he wanted to spend a little extra money so the GT-40P heads are out and "something else" is in. His combo will EASILY push over 350 at the crank now.

His engine bay should turn out sexxy as all hell too! I would bet that his engine bay will be pretty much every bit as sexxy as mine (if you think mine is sexxy).

 

[rcpasq]

The suspense is killing me!!! Did we move forward with this since March '07? I'm extemely interested in the outcome as I was planning a rebuild along the exact same lines. Thanks.

Bob Pasquale
Tech Performance & Engineering
Torque Monster Headers

 

[rocket 5979]

The suspense is killing me!!! Did we move forward with this since March '07? I'm extemely interested in the outcome as I was planning a rebuild along the exact same lines. Thanks.

Bob Pasquale
Tech Performance & Engineering
Torque Monster Headers

Yeah, this project hasn't taken much of a priority in my book lately with my planning for the one coming up. Apparently its owner felt the same over the nice warm summer months (too much jetskiing and motorcycling). Now that I have another "real" project coming up in the next few weeks we have worked on it a little. The engine is back in and almost everything is hooked back up. Just got to get the upper TFS plenum back on and a few other things and fire it up and tune it. There was no real timeline pressure so there wasn't much hurry.

It is only a day or two more of work but I am kind of busy with some custom differential stuff for that upcoming project. Suffice it to say that it is a PITA to pull a rear end out of a Mark VIII in a junkyard when you forget your wrenches.

 

[CDW6212R]

I've got a 2001 Cougar rear end, come and get it. Good luck on that rear, I'd like to have it under my 91 LSC. Night,