Question for guys with headers.

[Cameron]

I need to know if the exhaust manifold for the 4.0 is symmetrical.

That is to say, assuming there was room to do it, could I bolt the exhaust manifold from the left side of the block to the right side of the block?

Obviously, the reason I'm asking the people with headers is that if you still have your old manifolds, you could hold one above the other (looking at the port side of both) and see if they are identical in appearance.

Although I appreciate all the information I can get, It's important that you're sure about your answer.

Thanks in advance. This will save me plenty.

 

[SteveVB]

Cameron,

On my 91 (90 TM) heads the driverside and passenger side exhaust manifolds can interchange assuming the clearance exists. Both exit to the rear, or the front if you swap them, and I think would interfear with the accessory drives on both sides. The driverside manifold less than the pS manifold, its exit is more down than rear compared to the pass side.

FWIW


Keep in mind that the exhaust ports changed at some point to round from the D shaped, but the bolt pattern stayed the same. I know the 98TM castings have the round ports but previous to that I dont know.

Good luck with the project looking forward to the results.

 

[Cameron]

SteveVB,

Thanks for the response. The clearance of the accessories/ drive pulleys and belts is a non-issue at this point. We are simply trying to figure out what our options are as far as turbocharging the Explorer goes. As we see it, we have two options. The first is to fabricate a bracket that would mount before the catalytic converter. The turbo would mount to this bracket. The plumbing wouldn’t be a major issue. The problem with this configuration is the turbo would sit lower then the oil pan. We would need to fabricate a sump that would pull the oil out of the turbo after the motor stopped. This type of configuration would put everything closer to the ground. The second option is to put the turbo up where the battery is (Front driver's side corner in the 97 Sport). If I can mount the exhaust manifolds on the opposite sides of the motor, I could run the plumbing forward and up to the turbo (battery area). One of the guys at DPS Motorsports is doing a similar thing to his Honda. He moved the battery to the trunk and fabricated a custom turbo bracket that mounts to the motor. Although he has a front wheel drive 4 cylinder and doesn't need to flip the manifold, the principal is the same.

My brother-in-law already has a TC26 turbo out of a Toyota that he said is all mine. So, the rush is on to get this project rolling. We have Wastgates, blowoff valves and such (lots of spares floating around the shop).

Getting fuel to the engine is not a major issue. I guess DPS is working on the timing issue. I personally don't know much about that but he's working on it.

Anyway, I got some talented car builders working on this one.

Money isn't as big of an issue as time. DPS is in the middle of the racing season and most of his time is spent on his dragster. This fall looks to be a realistic goal for starting the actual install. I'm just being a good little soldier and getting everything ready.

Anyway, thanks for the info.

 

[rockylaurence]

Buy and compare a cheap set of gaskets to be sure.

 

[Cameron]

Rockylaurence,

That idea is so simple only a genius could have thought of it. Thanks for the excellent tip. Maybe I’ll go to Ford and they’ll let me see a pair (assuming they have them in stock) so I don’t have to buy them.

Again, thanks for the idea.

 

[niceguy]

my 2 cents

I'm just finishing up an overhaul of the top-end of my '94, and can add these observations (since I just spent the last 10 days looking at these parts).

The heads are interchangeable. You'll note that the plugs angle to the front on the driver's side and to the firewall on the passenger side.

The gaskets for the left and right exhaust manifolds are identical (but this doesn't mean that they're symmetrical...). There is an "inside" and "outside" and an implied "up" (the two slotted holes go down to facilitate installation). Note that the engine does not come from the factory with exhaust manifold gaskets. It's possible that Ford does not make them for rebuild purposes either. You might save yourself a trip to the dealer and go to your favorite parts store instead, 'cause I know that the Felpro kit contains them.

Having said all of this, a driver's side manifold should mount on the passenger head, and exit (more-or-less) to the front. Don't know about motor mount clearance, though. Hmmm.

But now you've got me curious: can you just take the passenger side manifold and flip it over so that it exits to the front ON THE TOP, and just bolt your turbo directly to it? I didn't try to put a gasket on upside down, so don't know if this would work. And of course, don't know if that arrangement would help or hurt what you're trying to accomplish.

Following up on the cheap-and-easy approach, perhaps a local junkyard has the manifolds already pulled for you have a look-see.

Sure sounds like fun!

 

[Cameron]

I definitely thought about putting the manifolds on upside down and bolt the turbo, more or less, directly to them. I think there is a space issue though. Of course I do like the idea of running dual turbos I already have one turbo. It's a CT26 out of a Toyota. If I ran dual turbos, I think I would need to get two smaller ones. Smaller turbos like the 16G cost about $800 each. My CT26 is free! Hard to pass that one up. The CT26 is a fairly larger turbo. It should marry with the 4.0 well.

 

[niceguy]

From the FWIW dept - twin turbo stuff...

My daily-driver is a '92 3000GT, but NOT the VR-4 twin-turbo 4WD monster. However, I keep up with a couple of mailing lists and message boards and read a lot about them.

If you get serious about the twin-turbo route, you might consider lurking around in a couple of these for awhile and learn what those guys are doing. There are also some good boards for the Nissan 300ZX, and the Toyota Turbo Supra.

The 3000 is a 3.0L, as is the 300ZX. Not sure about the Supra. A couple of those turbos might work nicely on a 4.0L. I know that some of the 3000 guys have got more money than sense, and are frequently upgrading turbos, wastegates, etc. You might be able to pick up some used (or even new-in-the-box) matching turbos from one of those guys.

You can find the 3000GT board at: (dead link)

A more technical group (mailing list based) is found at (dead link) - check out their archives, or subscribe. These guys are REALLY sharp and are a wealth of information. Note that they're pretty strict about their posting guidelines (those rules - they mean it). (And of course, they may laugh at you when you start talking about your twin-turbo'd Explorer... Might be better to lurk and NOT post!)

Assuming you're looking to race, you're going to face some interesting other "de-tuning/tuning" issues, depending on the boost you're going to run, etc. (What's the compression ratio on a stock 4.0, anyway?) It might be helpful to learn from somebody else's (expensive) mistakes.

Anyway, just thought this might help some. It's sounding more and more interesting already...

 

[Cameron]

Re: From the FWIW dept - twin turbo stuff...

You're right. Thanks for the links. I'll be sure to check them out. I frequent several clubs like (dead link)
They are a pretty good source for turbo related questions. Mostly though, I'm forced to learn as I go.

Originally posted by niceguy
It might be helpful to learn from somebody else's (expensive) mistakes.

You show me someone who's turbocharged an Explorer and I'll learn from 'em. Otherwise everyone will be learning from my expensive mistakes.

That’s why I'm taking it kind of slow. Crossing my Ts and doting my Is.

I don't plan on racing it. It's to heavy and to aerodynamically similar to my house. Plus, I like my grill guard and roof rack. With all those accessories and, the fact that the Explorer is a box, I would need 1000 HP to compete with 400 HP Toyotas. At least on road And, if I start pumping huge amounts of boost (and I most certainly will) something is going to give and it wont be cheep to fix.

I'm doing this because I want to do something different. Supercharged Explorers are not uncommon. 5.0 swap has been done. The only really unique mod I have heard of is Paul Gagnon's 3.8L Supercharged V6 swap. Although I think it's on hold now. Sow what the heck. The parts are readily available. I have access to a fully equipped garage (at least I will in the fall) and not only do I have access to some talented fabricators, I can tap in to the infinite wisdom of this Explorer club.

 

[Ray Lobato]

Well Cameron,
I'd sure like to see that puppy when it's done
Go head on!

 

[rockylaurence]

Paul is swapping in a 3.8L? Great idea! You'll be able to keep decent milage plus have access to all the V-8 performace goodies and transmissions. The Mustang 3.8L comes with tube headers. Paul let us know how it's going.