75mm Accufab throttle bodies, 347's, and 1998 Explorer Sports; an impossible dream?

[redavis460]

Hi guys, after a long absence, I've come back into my old project: a 1998 Sport (2wd) with a 347/M5R2 5-speed combo. The difference is, this time I'm giving it the treatment of TFS heads, custom cam, custom headers, and the like; with all that flow potential, I'm at the upper end of 70mm throttle body territory with the 6200 RPM redline, and possibly into 75mm TB needs. I've tried looking at some of the posts for some suggestions to solve the throttle linkage issues with Explorers and Accufabs, and it looks like the "86 to 93" Mustang is the proper starting point, at least for that. My question is this: is someone out there that anyone can recommend to perform the necessary surgery to one of these Accufab's to get this thing up and running? It looks like there may be one or two other issues related to wiring and getting it bolted onto the elbow (mine is one of those that has the external EGR); I'm seriously considering extrude-honing the elbow since TMoss doesn't fool with them, and possibly opening it up for the 75mm TB if needs be, along with any other suggestions anyone might have. Thanks so much for your help!

 

[vroomzoomboom]

all i did for mine was make a new elbow

 

[CDW6212R]

Ditto, make a new elbow with 75-90mm pipe curve. Tim and a couple of others have done that very well.

I have a 75mm that I tried to have my elbow ported to fit better. The stock elbow cannot be opened up more than about 70mm. I will use mine later on a 306 for my 99 Explorer, but I may just settle for a 70mm TB.

Welcome back and get started again.

 

[boominXplorer]

I was able to port my stock elbow and upper intake to accept and properly flow a 75mm throttle body. It took forever to do and to be honest if I drop the elbow it will probably crack in half it's so thin. 4 years, 3 trucks and 50k mi it's still good to go. I'm using a ported stock tb on it now but since I'm finishing up my cam install I am now finally looking for a 75mm tb.

 

[CDW6212R]

The two openings of the elbow can be ported to a 75mm size. It's the curved section that is not really more than 75mm on the outside diameter. I told the local porter I used to do what he could without making it too thin.

For a mild application, the OEM unit ported well should be fine. If the goal is much bigger power, the turn itself is too tight. I'd custom make something with more size than 75mm, and if possible a wider radius(which isn't possible in stock layout parts). It's the AC that's in the way I believe, which makes that elbow so tight.

For a serious engine, select a much better intake for a stroker and the 6000+ rpm, and put together a better TB and elbow that are in the 90MM range. That's all brain storming of course, every person has their own idea of what's a serious engine. Fun to talk about it though, night.

 

[redavis460]

Thanks so much for the responses guys. I've got several solid issues that I've got to recognize, and I'll have to act accordingly:

1) I'm wanting to keep the EGR system intact; so, unless anyone out there has any experience making a larger elbow from scratch that has an external EGR boss, and is willing to sell me one, I'm stuck with porting and polishing the stock elbow. I'm thinking, though, that extrude-hone polishing the elbow i.d. and porting the TB end for a 75mm throttle body might be about all the flow I'm going to get under these circumstances (even though it might mean losing the small turbulence hump at the EGR passage that could affect EGR distribution to all cylinders evenly). I'm keeping in mind that a 70mm port should probably flow at least as well as a 75mm throttle body (since the shaft and butterfly are absent), the sharp bend notwithstanding - but of course there is nothing I can do about the bend in an Explorer application, as you say.

2) I guess since no one has said differently, the Accufab 86-93 Mustang 75mm TB application should be my starting point? I know there will be some modifications to be done on the throttle linkage; is there a shop or individual who has been down that path before that I could contract for their services? My fabrication ability at this point is somewhat limited (divorces do that as you probably know), and accrued knowledge is a good thing! Also, as far as the IAC motor and the throttle position sensor, I take it that the Explorer IAC will bolt up, but when I get to the TPS, I've got to choose between modifying the Explorer TPS by clearancing the mounting holes, or rewiring for a Mustang TPS (something about the Cobras reading a different voltage?) along with the Mustang connector on the wiring harness, being careful that the color coding may be different?

 

[CDW6212R]

I think all but one of those members here who made their own elbow, kept the EGR. They cut off the elbow around the EGR hole, and welded that into the new pipe, and it works great.

Extrude honing an odd part they don't normally do, will be very expensive versus having an elbow fabricated. Search for the threads here which depicted how they made their elbows.

The Fox Mustang TB is what you want for lowest cost and ease of alteration(the Explorer TB arm has to be cut off and attached to the new TB. The Fox type TPS sensor is different than later models, the mounting holes are enough different that it's best to use those for the Fox TB. That has a different wiring connector, so you also need the pigtail of the car wiring, or cut off and splice the wiring of the Explorer pigtail to the Fox TPS(that means it wouldn't be plug and play for the next time or trouble shooting).

 

[vroomzoomboom]

i can contact the member who bought my old supercharger setup. when i sold it, i gave him the elbow with it, but i dont think he is using it (you would also have to like a black elbow with blue true fire flames on it lol). here is how i made mine. i took the stock elbow, made a jug around it, bought a (i think) 90 degree 3 inch mandrel truck exhaust pipe, and took a gasket to a local place that laser cuts metal and had them cut 2 flanges for the intake and throttle body side and a egr flange as well. i then bolted the flanges to the jig, cut the pipe to fit in the jig, welded it, and put jb weld on it just to make sure i didnt have any pin holes that would make a vacuum. sanded it smooth, and had it painted.
as for the linkage, i cut a piece of 16 gauge metal, drilled 2 holes in it, and the linkage on the throttle body so it could be bolted to the throttle body. i bought a couple of throttle linkage balls (holley has them) and notched a hole in the sheet metal i bolted to the linkage for the ball. it took a little tinkering to get it right. most guys have chopped the bottom of the linkage off, and welded the explorer one to it. i did it this way incase i ever wanted to sell it and a mustang guy wanted it.

 

[Centaurus5.0]

From:http://www.stangnet.com/mustang-for...cuss-throttle-bodies-is-bigger-better.692440/

"Much debate is brought about over throttle body sizing and the effects of each.

I decided to bring out a little fact and a little common practice, so pardon some of it being unorganized, but I put this together quickly and wanted some feedback and thought. If there is anything you see that you feel is inaccurate or bias please post up and we will go from there

I notice that there are a few stangers out there with the notion that a bigger throttle body has no effect on engine performance or drivability and is needed to get the correct amount of air in the engine. I attend to show this by thought that this is not the case all the time. These numbers are accurate ballpark figures. Not exact.

At 6,000 rpm a 347 can flow 600cfm. That is with NO restriction. Any 347 or similar has a ton of restriction. That cfm rating does not include a heads, cam package on it. The cam only is open for little amounts of time, commonly referred to as the duration of a cam. So the cfm rating of the engine is further cut.

Stangers are routinely sticking on throttle bodies that flow two to two and half times greater than their engine sees at its peak.

I have to ask...why?

If you've got a throttle body that delivers 100% of the peak air requirements of your engine when the throttle plate is fully open, you have control of the air throughout 100% of the throttle position range. If you go to an oversized TB that delivers 100% of the air that your engine can consume while the throttle plate is only 60% open, you have given up usable throttle-control range for no advantage.

Guys that are constantly defending the oversized throttle bodies are only talking about wide open performance (WOT). What about the 99% of the time that we cruise around at part throttle?

With a bigger blade like on a 75mm throttle body, the throttle modulation becomes more difficult. The gas pedal modulation becomes touchier. The reason why is do to the fact with the larger surface area of a 75mm blade compared to a 65mm blade, you get more air that passes thru with less pedal effort. This causes the gas to be less manageable and many post of bucking problems do to the very problem described above.

From Tom Moss, do to the nature of velocity the air charge moves faster (for each degree of TB blade movement) when using a smaller TB and that fills the cylinder better at lower rpms. Velocity is effected for part throttle performance as well.

Again, look somewhere else for a restriction, not an oversized throttle body.

An Accufab 65mm throttle body flows more than enough for a 347 stroker with 664cfm continuously, while the 347 would see 600cfm if it had no heads, cam, or intake on it, which of course is impossible.

Enthusiasts need to quit ignoring the facts.

Read an article from the top throttle body maker them self and let them tell the tale:

THE AIR PUMP UNDER YOUR HOOD

By George Klass – Accufab Designer/Tech

What size throttle body or carburetor do I need?

Good question but the real question should be “how many cubic feet per minute (CFM) of air will my engine require?”
An engine is an air pump. Based on the size of the engine (displacement) and how fast it will be spinning (RPM), it will pump out a certain amount of air. Works just like an air compressor. Of course, there are many variables to CFM requirements, such as cylinder head flow capabilities, intake and exhaust manifold flow capabilities, etc., but the basic engine block will pump a certain amount of air over a specified period of time, measured in cubic feet of air per minute.

If the engine is to be carbureted, it should be a relatively easy decision to pick out the correct sized carburetor. Carburetors are defined by CFM. If your engine calls for (or pumps out) about 664 CFM, the correct choice is probably a 650 CFM carburetor. Unfortunately, throttle bodies are rarely defined by CFM ratings. Instead, most throttle body manufacturers define their throttle bodies by the inside diameter of the unit, measured at or around the throttle blade, and usually in Millimeters (MM). Unless you have a direct correlation between the measurement in MM and the related CFM of that particular unit, the selection is going to be based on “best guess”.

And to further complicate the “guessing” process, all throttle bodies of the same dimension, do not have the same CFM rating. You might think that Brand A’s 75 MM throttle body would flow the same as Brand B’s 75 MM throttle body. Such is not the case, because all throttle bodies have a “major obstruction” in the middle of the air path, namely a throttle blade and shaft. How well the air flows over and under this obstruction will define the CFM a specific throttle body will flow. A big fat shaft with the attachment screws for the blade sticking up into the air stream will impact the CFM of that throttle body.

While most enthusiasts with EFI engines continue to purchase throttle bodies based on Millimeter size, caring little about the actual CFM ratings, the carb guys purchase carburetors based on CFM ratings, caring little about the size of the throttle plates. Score one for the carb guys.

But, back to the original question, “how much CFM do I need”?

Below is a chart with the CFM requirements, based on displacement (in cubic inches) and RPM. This chart will work for any piston engine with any number of cylinders. After you have determined the CFM for your specific engine combination, you can then choose the corresponding throttle body or carburetor size to best fit that combination.

DISPLACEMENT………….6000 RPM……….6500 RPM……….7000 RPM
280………..…………………486………………..527………………..567
290……..……………………503………………..545………………..587
300………..…………………521………………..564………………..608
310……..……………………538………………..583………………..628
320……..……………………556………………..602………………..648
330………..…………………573………………..621………………..668
340……………..……………590………………..639………………..689
350……..……………………608………….…….658………………..709
360………………..…………625………………..677………………..729
370………………..…………642………………..696………………..749
380………………..…………660………………..715………………..770
390………………..…………677………………..734………………..790
400………………..…………694………………..752………………..810
410………………..…………712………………..771………………..830
420………………..…………729………………..771………………..830
430………………..…………747………………..809………………..871

This chart should give you a general idea of the amount of air your combination will pump. Engines will pump less air because of the restrictions in the cylinder head or intake manifold design or valve lift, or all three. But, the chart still gives you a ball park starting point.

One other thing to know. A carburetor requires air speeding over the venturi to draw the gasoline into the mixture. Using too large a carburetor (high CFM rating) will usually cause derogatory performance in the lower or midrange. This is because the lower air velocity is inefficient in mixing the gasoline with the air. In general, and particularly for street use, a slightly smaller carb (less CFM) will give better overall performance.

With an EFI system, this is usually not a problem. The throttle body only controls air flow. A computer monitors the gasoline supply and the mixing of gasoline and air takes place inside the intake port, and not inside the carburetor. Using an oversize throttle body is not nearly as detrimental to low and midrange performance as is using an oversize carburetor.

So, to find the CFM ratings of a carburetor, all you need to do is to look in any catalog from Holley, Edelbrock, Barry Grant, etc. That’s how the carburetors are listed. To find the CFM ratings for a throttle body is going to be more difficult, unless you happen to choose an Accufab throttle body.

Because the Accufab throttle bodies are designed to “race engine specs”, the flow ratings are going to be greater than most of the other aftermarket throttle body designs, so don’t automatically expect a “75 MM Brand B” throttle body to flow as much as an Accufab 75 MM unit.”

Top reasons why mythical ‘gains’ are seen by larger throttle bodies:

1. The owner did not port match the intake or have an intake that had a same or larger diameter intake opening. The owner then port matched the inlet or switched with a different intake.

2. The throttle body was swapped after a new or rebuilt engine had broken-in. It is common knowledge that a engine will loosen up and gain clearance tolerances which reduces friction. For example, if a stanger had a 70mm throttle body on a freshly rebuilt 331 and dynoed 350rwhp with 500 miles and at 7,000 miles swapped to a 75mm throttle body and gained 8hp ‘across the board’. You may want to think about engine break-in and tolerances of an engine to be the culprit not the larger throttle body.

Car and Driver do long term testing on cars/trucks as well as others. They do baseline runs when new and do more performance testing at 50,000 miles. Every single time the 50,000 mile period shows to much noticeable quicker to 60mph and ¼ mile times. Be careful on a new engine thinking the throttle body gave you the gain when it was an extended period between a dyno or track session.

3. Another thing I have seen is when there are dyno graphs that show gains ‘across the board.’ This simply can not happen at wide open throttle if you take this example: Take a 302 engine with a 65mm throttle body and you add a 75mm throttle body. Let’s say it shows a gain from 2,000 rpm – 6,000 rpm. That would imply that the 65mm throttle body could not flow enough at 2,000 rpm which is guaranteed not to be true. So what is the culprit? Check when the dyno was done compared to the new dyno? What was the mileage? Temperatures? Different dynos? Were there any other changes along this timeline or tuning? Then you get your answer. You will not see gains ‘across the board’ when you are dealing with N/A 302’s or even strokers under 350 cubic inch. The 65mm throttle bodies flow enough. You may see gains in the top half of the rpm range if you have some healthy parts on a stroked engine.

4. It is done inefficiently by using our own seat of the pants. Many that make the unnecessary swap think since the gas is touchier assume they have gained power by ‘feel.’

5. Much ‘testing’ is done at the track and many post how X stanger gained X mph with just a throttle body change. So again ask this stanger was the track the same? Headwind/Tailwind the same? Same shifting speed? Same 60ft time? Same rpm shift? Same day? Same or similar temperatures? This may seem tedious but many factors remain. A dyno will help take care of some of the ‘questions’ by taking out some other parameters that change.

In short, if there is information given about a gain look for the simple things like: Were there any other changes to the combo? Was the intake port-matched? Was the engine new or freshly rebuilt recently? Were the dynos the same? Was the temperatures/humidity the same?

The most accurate way to see if a larger throttle body gives you a gain is to do a back-to-back dyno test from one throttle body to the next. That way you have same mileage, same temperature, same dyno, same supporting parts, and same parameters in general. But be wary of promotional dyno test for a company or brand.

There can be instances were gains can be seen, on track cars that see HIGH rpm and have larger cubic inches that us 5.0L stangers usually see. And the gains will be up top in the higher rpm.

Throttle Body CFM Flow Ratings:

Stock 5.0L 60 MM - 526 CFM
SVO 65 MM - 540 CFM

Accufab:

65 MM - 664 CFM
70 MM - 787 CFM
70 MM - 896 CFM (Race version)
75 MM - 924 CFM
75 MM - 1045 CFM (Race version)
80 MM - 1142 CFM
85 MM - 1322 CFM
90 MM - 1369 CFM
105 MM - 1550 CFM

Holley:

65 MM - 750 CFM*
70 MM - 790 CFM*
75 MM - 840 CFM*
80 MM - 892 CFM*

*Information given by Tech Rep.

BBK:

70 MM - 726 CFM

Edelbrock, Ford Racing and Professional Products have no cfm information after calls/emails.

Information to keep in mind when picking out a throttle body for your application:

A 300 cubic inch engine (302 c.i.) flows 521 cfm (ballpark) at 6,000 rpm.
A 330 cubic inch engine (331 c.i.) flows 573 cfm (ballpark) at 6,000 rpm.
A 350 cubic inch engine (347 c.i.) flows 600 cfm (ballpark) at 6,000 rpm.

With the above information from Accufab's website, you can see that the aftermarket throttle bodies offered flow much more than your engine can breath (302-347). Those cfm ratings are even given with NO restrictions and of course our engines all have restrictions, via our heads, cam, intake packaging. An actual running engine flows somewhere in the neighborhood of 200-400 cfm with some rough math. The aftermarket throttle bodies flow two times this amount.

In short, be careful on picking 'too big' of a throttle body for your car. An application with boost (forcing air) allows for you to efficiently select a bigger throttle body, although N/A engines do not.

Throttle Body 101 from Accufab article: http://www.accufabracing.com/article 2.htm

Feedback welcome:nice:

If you dispute this information feel free to post up"

 

[Centaurus5.0]

And yes, I am trying to save you from yourselves.

 

[vroomzoomboom]

well.....im stroked, and forced induction. not really sure where i fall in this lol.

 

[CDW6212R]

EFI does not have the problems of A/F control varying with the airflow capacity of the TB, but a carburetor is a whole different monster. With EFI it comes down to the capability of the computer, how well it is tuned to manage what airflow it sees.

An oversize TB will create problems with untuned combinations, no doubt. It takes a good experienced tuner to make a TB work well at all, that is "too big."

I know a SBFtech and Corral member who has built several 302-347 sized engines, and all have larger TB's than would be expected. He regularly gets better fuel mileage with the bigger TB's and equal throttle response, equal or better power at all lower rpm's. I doubt he owns any TB smaller than a 75mm. He has put a 90mm TB on 306's with a big intake(TFS R or Systemax II). With tuning, and they all seem to be EECIV's, they all idle great and anyone could drive them, all manuals, pick a gear at 15mph.

You can screw up anything, and some people can make anything work. Figure out what you want, and get what's needed to make it happen.

It's all in the tuning. Regards,

 

[redavis460]

"Much debate is brought about over throttle body sizing and the effects of each.

You and Don both make interesting points; and, like you guys suggest, I've tried to talk with the folks that have much more experience than I have as to which direction to go. Thomas Moss seemed to think, and no doubt rightly so, that a 70mm would be the best compromise between dollars and effort spent vs horsepower gains, and the folks at Accufab concurred with that thinking, and that the 75mm might help slightly at revs over 6000 rpm. In trying to at least get conceptually into the ballpark, I remember that a strong Boss 351 pushing about 400 horses in the 1970's seemed to be at home with a Holley 750 atop; oddly enough, measuring the surface area of the opening of this carb is, if I did my math correctly (Disclaimer: I'm not an engineer but I have played one in a classroom), about 6.2" - and, a 70mm throttle body comes in at about 6" (75's come in at about 6.8"). I know the comparison isn't exact, because you have air AND fuel involved, but it at least helped me to hopefully find some similarity to what this engines needs are. Don, like you say too, with the correct tuning, many things can be made to work together: the stock 302 in these cars made what, 250-275 at the flywheel (?) and Ford's millions ($) came to the conclusion that a 65mm was the best match; but, I've heard that the Infiniti's old Q45 came with something like a 90mm TB stock? From the looks of it, a larger throttle body can be tuned to work below it's full potential; however, with one that is too small, when you are out of flow, you're out of flow.

Another thing evidently to consider, according to TMoss, is the flow potential of the heads. When I told him I'm going with the FTI CNC 203's, and if he could port the stock manifold, he immediately told me to go ahead and step up to something like the Holley systemax, evidently regardless of redline; and, I think this drove part of his recommendation to step up to the 70mm.

So, with that said, thanks to you guys input, I've gone ahead and decided to start things with the 70mm accufab; I figure that this decision will at least get me going into the 5000 rpm range safely. I have made contact with Bob at extrude hone to see what his thoughts and pricing would be on doing the stock elbow; if, as you guys say, it becomes cost-prohibitive, I may take vroomzoomboom up on his most generous offer if it is available. One thing is for sure, compared to the old carb days, this EFI stuff can get complicated in a hurry - not to mention expensive...but the results are incredible if done right.

-Russell.

 

[CDW6212R]

When I bought my 75mm to use with a 347 in my Explorer, the restriction of the elbow wasn't clear to me. Plus I was considering the GT40 intakes to be viable performance choices. Those are not, the elbow and the intake is a bad choice for maximum performance, if you ever go past 5000rpm. The Systemax II or the TFS R are the top dogs for an EFI stroker, even in the heavy Explorer.

But the elbow is a huge bottleneck for a NA engine. I would make that bigger for sure in the normal layout/location, and a 75mm TB would then be a minimum. With that stock level of elbow, the 70mm is plenty because the elbow is much more restrictive.

My 75mm will still go on my 347, but into my 91 Lincoln. That will have a Edelbrock RPM II intake, and in the Fox chassis it uses a large aftermarket elbow, any size up to 4" is common. I'll build a 306 for my conversion from V6 later, and that will use a ported(T Moss) GT40 upper, my mildly ported elbow, and a 70mm TB most likely.

All of this thinking is great, but also moot. If you cannot in some way open up the exhaust manifolds, the TB/elbow/intake/heads are minor issues. The primary pipes need to be at least 1 5/8", with 2.5-3" collectors, and full dual exhaust, end to end. Nobody has yet done that, because(for the same reason), everyone keeps reading the "smaller parts are good enough" logic. That means what you research about a carb only needing to be 600cfm for 6000rpm, or the 65mm TB is good enough for 6000rpm, that's scientific theory, it is not real practiced experience. In real life, a 351 engine will make great power with a 900cfm carb. The right heads, intake etc, will get you 500hp at 6500rpm. The logic says the huge carb is a waste, but in real life it is not.

If you find a way to install headers(or manifolds) with 1.75" primaries, and bigger than 2.5" collectors, and big pipes(2), two mufflers and tail pipes, sized nearer to 3"(x2), you will gain a ton of power versus what the TM headers and single mufflers give you. That will create a significant lean condition, tuning required to add enough fuel, to bring back the A/F ratio.

This is all just my opinion though, I will eventually get this done with my vehicles, yes I'm slow, and getting slower.

 

[Centaurus5.0]

Honestly friend, this build is a pipe dream. Are you really going to put $2,800 race heads on an Explorer? What you're talking about building is a $15,000 motor. Then your going to need a fresh transmission, major suspension mods, and then yada yada...

If your this confused over a throttle body, your better off handing Roush/Yates your wallet and letting them decide how much lunch money you can have while they build you a winston cup motor.

I was a young dreamer too once. I know where you are coming from.

A set of 4.10 or 4.56 gears and a tuner would be good start on a stocker until you get your feet wet.

 

[Centaurus5.0]

well.....im stroked, and forced induction. not really sure where i fall in this lol.

A roots blown motor is about the only exception on a sbf where bigger is better.

 

[CDW6212R]

Well said. Set your total budget, and what you could spend for each important system of the vehicle. The transmission is one, the suspension and normal operational things need to be in excellent condition. Make sure you address the many other things that have to be great along with the engine. The PCM flasher and a reputable tuner will be required, begin planning for those now. You will need the tuner quite a bit along the way, so hunt for someone who can be a friend in a way too. Night,

 

[redavis460]

Good advice guys; and, you are right: the risk is always present of spending too much money on a project when, for instance, almost any used SUV made within the last few years could potentially be obtained far cheaper, with performance beyond anything we could hope to achieve in the "modified Explorers" section (depending, of course, on how we define being satisfied). However, people have different motivations; for me, it will probably be the last small block Ford I ever build, and frankly, fox body vehicles and early mustangs - from a driving experience standpoint - I've never found satisfying. I kind of see this as conceptually similar to an early Bronco with a Boss 302, or a big Bronco with a 460; from that perspective, a 347 EFI Explorer offers attributes the others lack, albeit with certain technical hurdles to overcome - and plenty of (probably similarly insane) people have fallen victim to performing these types of aforementioned swaps - but it's definitely not for everybody. In retrospect, when the build was started seven years ago, my mistake was in allowing the machine shop to talk me into the 347 kit; every other problem has stemmed from the fact that the platform as designed is, as you say, at the limit at 302 cubes. Fortunately, the engine is backed by an M5R2 and a 31 spline 8.8; I don't plan on asking the unit to either run the 24 hours of Daytona, or running slicks at the drag strip, so, with my driving habits, it should satisfy me for years to come.

On the exhaust issue, again, according to my calculations, two 2.5" diameter pipes is the same opening as one 3.5" pipe; as you have no doubt found out Don, the closest I can come is a single muffler with 2 2.5's in, and one 3.0" out: definitely a problem area, as there is no way to run duals and keep the spare tire setup. This does bring up something else that does have me puzzled: how exactly is it that LS3's and other performance engines of the modern era get by with what look like somewhat restrictive exhaust systems, yet manage to make power levels well in excess of our 347 goals, cats and all? My header guy tells me that we will be able to buy some room on the headers by not requiring the flange to be in the stock location - but you are correct, the v6-designed engine bay is less than ideal....but, seeing as how my first car was a 1978 Mustang II V8 that eventually saw a 351, this looks almost easy by comparison; we shall see.

With the tuner, already done; I've purchased the code for the NRT1, and have Binary Editor standing by to be done by some of the brains at one of the other forums. I've also upsized the fuel injectors and the MAF as recommended by Chris at poweraddersolutions. The 8.8 has a fresh rebuild, as well as the M5R2; Bilstein shocks, fresh bushings, control arms, torsion bars, steering gear, V8 donor vehicle sway bars, traction bars, multiple leafs, high volume fuel pump, FPR...the list goes on, but I've tried to be comprehensive.

In the final analysis, every project I have ever done - even the expensive ones - has invariably led to knowledge that paid dividends in excess of cost at some point in the future; and, there is no telling where this engine could end up at some later date, as, if it does prove to be a dead end, half a day's labor pulls it out to be put in something else. Our Explorers are interesting to me in that they are the last platforms ever built with the old Windsor v8's; if Ford of America had been more like Australia in that regard, they perhaps would have made a run of exactly what I'm trying to put together here: 2 door Explorer Sports with 347 V-8's and 5-speeds....since they didn't, I guess (admittedly) fools like me have to struggle in futility (and to make things worse, there is an early Miata that my son drives sitting in the driveway right now..........so it is very tempting to find those take-off gt40p's a new home).

 

[Centaurus5.0]

I see.

I could have sold you a 450hp 347 with 5,000 miles on it for $4000 a few weeks ago. I still have the Holley Systemax Intake (with 70mm Edel TB) and heads sitting here.

I've learned to buy parts used whenever possible. Like buying a new car, let the next guy take the sticker shock for new.

If you have your heart set on an Accufab I'd inform them of your plan, they would have no problem modifying a new TB to an Explorer linkage. But if I were you, a $100 bill to Maxbore to get the most out of a factory 65mm would satisfy me on a 347. No elbow mod needed.

 

[redavis460]

Oh man, Centaurus5.0, I wish I had your connections! I emailed the folks at Accufab about exactly that (modifying the linkage) on Wednesday, and here was their response:

"The 75mm unit will give you a little more power above 6000 RPM. As far
as the linkage modification, we do not recommend it so you are on your
own..."

I obviously was talking to the wrong folks on the other end....Do you know anyone I can talk with? Thanks for all of your help!