SOHC V6 Supercharger | Page 10 | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

SOHC V6 Supercharger

The purpose of this thread is to discuss the design and possible development and installation of a supercharger for my 2000 Sport SOHC V6 engine. I have no first hand experience with forced induction systems and want to learn from forum members that have them on their vehicles. While I don't plan to implement a turbocharger system, there are many problems common to all types of forced induction systems.

The easiest and least expensive solution would be to modify a Ranger SOHC V6 Banshee kit and purchase a used Thunderbird supercoupe positive displacement blower. However, the kit makes no provisions for an aftercooler which I think is beneficial even with only 5 psi of boost.

The Explorer Express supercharger kit includes a quality looking manifold but one is very difficult to obtain.
sc1.jpg

Once again, there are no provisions for an aftercooler.

I suspect the best solution for me would be a centrifugal supercharger with a water aftercooler. With my oil coolers and remote filters I have very little room in front of the radiator for an intercooler. I am interested in a boost in the range of 5 to 8 psi - enough for a significant performance increase but not so much to adversely impact reliability and require beefing up of engine internals or the transmission/torque converter.

Procharger sells a kit for the 2005 - 2010 Mustang V6.
MustangSC.jpg

But the Mustang configuration is opposit to the Explorer - intake on left and battery on right. Also, there is a lot more room between the engine front and the radiator rear on the Mustang than on the Explorer.


Vortech also makes a kit for the Mustang but there are the same problems.
MustangSCV.jpg

MustangSCV2.jpg


The logical location for a centrifugal supercharger is the same side as the air filter box and intake manifold inlet port. Unfortunately, that is where the alternator is located. I'm investigating the possibility of replacing the belt driven power steering pump with an electric motor driven pump and then relocating the alternator to the old power steering pump location.
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





mass airflow as a performance indicator

. . . Things like timing affect performance so much that mass air flow might not be a great indicator.
My motor currently moves a fair amount of air thru it, but the timing is so far retarded that the power isn't there.

After reviewing the seven WOT datalogs I performed for James Henson's custom tune for my 90 mm MAF sensor and 75 mm throttle body I have to agree that mass airflow is a poor performance indicator for WOT runs. The rapid increase in engine rpm is reflected in the mass airflow to the degree that the negative impact of knock sensor retard and non-optimum air/fuel ratios is undetectable. I noticed that the PCM computed engine "load" maximum decreased for each tune iteration to optimize the air/fuel ratio. I also noticed the load graph was similar to a torque graph so I compared it to the 13 dyno runs I made prior to the custom tune. With the stock intake system the torque peaked slightly above 4,000 rpm. After the intake mods and tune the load peaked slightly above 4,500 rpm. It seems plausible that enlarging the intake system diameter would raise the peak torque rpm. I need to learn more about how the PCM computes load. If its based on a percentage of a PCM computed max torque then it would be a good performance indicator. A lowering of the percentage of the max torque for the peak load would reflect an increase in the max torque (a performance increase). I have the source code for an old generic Ford Strategy (PCM firmware). Since it is over 8,000 pages long it will take me a while to determine how load is computed.
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





Normally, I want the intercooler pump to be running any time the engine is running and not running when the engine is not running just like the fuel pump. The Bosch intercooler pump draws between 2.5 and 3.5 amps depending upon application. According to the installation guide for the Stealth 340 it can draw as much as 16 amps at 65 psi and a 30 amp circuit breaker is recommended (stock is only 20 amps) so the fuel pump electrical source should not be used for the intercooler pump. However, I can add another relay controlled by the PCM fuel pump signal by tapping into the LB/OG wire that goes to the fuel pump relay. If desired I could run the wire tap to a driver accessible switch to manually disable the intercooler pump relay.

Using the fuel pump trigger circuit is a good idea for the IC pump etc.

You mentioned the 340 pump before and it isn't a big deal, but why such a big pump? Those are really only needed for big power like 600hp+, rwhp.

I don't plan to get anywhere near those levels, but I have thought of an idea that would apply to those, and be good for any performance application.

Why not add a second pump inside the tank, for any application where the volume needs to be higher, and altering the tank pickup is considered? Lots of people upgrade the fuel lines, the fuel rails, injectors, and the pump.

When you get that close to needing to alter the pickup or go to an external pump, how about just adding a second pump, and outlet tube to the pickup assembly? I'm not sure I can do my project without making the OEM pickup tube larger(to #6 AN), and if I need to do that, I think I'll add another tube, and pump.

If you went that route, you could use two common 255ltr/hr pumps, and run one only at WOT. With the proper wiring circuits and an under hood(or in the quarter panel) switch, you could swap the pump functions. When one pump goes bad(the constant pump surely), open the hood(or in the quarter panel) and flip a switch, and drive away.

That would add reliability to a high stress fuel pump system, very valuable for long distance travel.
 






tip in theory

. . . You mentioned the 340 pump before and it isn't a big deal, but why such a big pump? Those are really only needed for big power like 600hp+, rwhp. . . Why not add a second pump inside the tank, for any application where the volume needs to be higher, and altering the tank pickup is considered? . . . If you went that route, you could use two common 255ltr/hr pumps, and run one only at WOT. With the proper wiring circuits and an under hood(or in the quarter panel) switch, you could swap the pump functions. When one pump goes bad(the constant pump surely), open the hood(or in the quarter panel) and flip a switch, and drive away.

That would add reliability to a high stress fuel pump system, very valuable for long distance travel.

That's a clever idea Don. I agree that for steady state conditions 340 lph is way more capacity then I'll ever need. However, I have a tip in theory (that may not be valid) to justify the large capacity pump. In the early 2nd gen Explorers the fuel pressure regulator (FPR) was mounted on the fuel rail. It regulated the fuel pressure at the rail based on manifold vacuum which means it quickly responded to throttle plate changes. On my Sport the FPR is in the fuel tank with no vacuum connection. When the throttle plate is rapidly opened the PCM detects that from the TPS output and widens the injector pulse width in a manner similar to the pump in a carburetor. This keeps the engine from stalling or hesitating during the transition from light to heavy demand. I have read some hints that maybe the standard non-return fuel system does not respond to the transition quickly enough and it is difficult to compensate for the slow response by temporarily changing the pulse width (tip in). A larger capacity pump should be better able to keep up the fuel pressure. Later, I hope to control the fuel pump with a pulse width modulated motor speed controller using the TPS voltage as the control parameter. Then the pump motor won't be using so much current just to send most of the fuel thru the bypass and back into the tank. I don't want to add it now to eliminate it as a potential variable for James to contend with when doing the custom tune.
 






I think that transition part of the tuning is something James is familiar with. I understand the idea of it being difficult, and it's an interesting reason not usually mentioned to go with the return style system, but I'd feel comfortable with letting the PCM tune handle that.

I'd ask James for his opinion about that issue, if it is worrisome. The computer tune is very extensive and complicated. I think I need to begin learning about it, so I can have some understanding and input for my cars. I know some "Mustang" guys on a forum who do their own tuning, with various aftermarket devices, speed density or MA, and they are very good at it. Patience is the key they point out, it takes a long time to get things ideal, and those guys are working with the old EECIV that I've been dogging for years.
 






percent load

I think that transition part of the tuning is something James is familiar with. I understand the idea of it being difficult, and it's an interesting reason not usually mentioned to go with the return style system, but I'd feel comfortable with letting the PCM tune handle that.
I'd ask James for his opinion about that issue, if it is worrisome. . .

James is the one who suggested I purchase the Stealth 340 although he didn't say why and I didn't ask. I've read some discussion by him and rocket 5979 years ago on a supercharger thread that expressed some concern about the pumps available then but I don't remember the details.

I found the parameter percent load in the generic Ford Strategy source code: "pct_load is an estimate of (manifold absolute pressure/ambient pressure). pct_load has the characteristic of going to 1.0 at any altitude and any engine speed when maximum air flow is reached, thus indicating that the driver is demanding maximum torque. pct_load does not use bp in its calculation and is therefore immune to any inaccuracy in bp."

I think bp is the bypass air flow due to the IAC valve

pct_load = totldst / air_ld_wot

totldst is an estimate of what load would be at the current engine speed, throttle position, and EGR rate, and at EEC Standard Temperature and Pressure (ESTP).
air_ld_wot = Maximum load at current engine speed based on mapped engine behavior at ESTP

I think "mapped engine behavior" is performance data determined during factory testing. If so, then a decrease in the maximum pct_load indicates a decrease in totldst or - stated another way - less load on the engine for that rpm. That may indirectly mean an increase in performance.
 






Main intake 1st prototype

I received enough parts to assemble the first prototype of my main intake.
MIProto1.jpg

I wish I had purchased a 45 degree elbow with longer legs but didn't find one readily available. I think the distance from the plenum inlet will be too short for the other leg to line up with the corner of the air filter enclosure. I didn't have a reference measurement for the distance from the plenum inlet to some point forward on the engine. I'll have to wait until I receive the Banshee kit and an M90 and temporarily mount it to adjust the leg lengths. I also think the distance between the elbow and the throttle body (stock one shown in the photo) will be too short to mount the throttle and cruise cable housings.

One set of holes on the universal MAF sensor adapter are fairly close to lining up with the stock throttle body.
MAFSAdaptEx.jpg

Elongating the holes in the correct direction and adding a gasket should be adequate. I'll do the same thing at the plenum inlet end using the Banshee kit gasket as a template for the mounting holes.

I purchased ported couplers since they were only $10 each even though the ports are probably too small in diameter.
CplrwPorts.jpg

They hold things together for now. In the future I'll get the muffler shop to cut a section of 3" diameter stainless steel tubing and weld or braze "bungs" into each one according to my needs (size, orientation & quantity).

EDIT: I spent some time in the plumbing section of Lowe's and didn't find any fittings with 1/8" x 27 thread. All of the 1/8" fittings had a finer thread. The coarser thread started at the 1/4" diameter size fittings. I also didn't find any listed on FastFittings.com which I have used extensively for my oil coolers/filters work. Lowe's did have some fairly inexpensive reducing couplers for use with PEX pipe. I bought a 3/4" to 1/2" and a 1/2" to 3/8" to drop down in size from the intercooler pump 3/4" outlet to my auxiliary ATF cooler (intercooler heat exchanger to be) 3/8" inlet/outlet. I think the intercooler inlet and outlet is 5/8" so I'll have to find something else to increase diameter from the ATF cooler outlet.
 






Intercooled kit complete & being shipped

The Banshee intercooled supercharger kit was received 7/3/13. I have lots to do before starting the installation:

1. Finish removal of A/C refrigerant manifold, cover condenser & compressor ports. Completed 6/28/13
2.a. Restore stock tune, Completed 7/1/13
2.b. Upgrade X3 firmware, Completed 7/1/13
2.c. Reload custom tune, Completed 7/2/13
2.d. Troubleshoot datalog issue. Completed 7/2/13
3. Switch from low grade fuel to premium high octane fuel. Completed 7/7/13
4. Perform datalog for knock sensor retard issue & decide on course of action if still present.Completed 7/16/13 - decided to desensitize knock sensor in custom tune
5. Install high flow fuel pump since original stock pump could be weak reducing baseline performance.Completed 8/3/13
6. Check 1 or 2 Champion Truck Plugs to make sure still in good condition. Completed 6/30/13
7. Install vacuum/boost gauge.
8. Record vacuum readings at various engine speeds.
9. Establish pre-forced induction performance baseline on dynamometer.
10. Acquire 2.8" or 2.7" blower pulley. Completed 7/9/13 - 2.7" received
11. Acquire M90. Completed 7/9/13
12. Acquire intercooler pump. Completed 7/3/13 - Bosch Cobra pump, harness & mounting kit received
 






When was the last time you was on the dyno? What was the results and has anything changed sense then? Looking forward to seeing some things coming together
 






earlier dyno results

I had around 13 pulls on the dyno with various configurations of intake, throttle linkage and selected transmission speeds. All were with my stock 55 mm MAF sensor and 65 mm throttle body and stock tune. The one below is with my modified throttle linkage and low restriction air filter. It was with speed "2" selected which is 3rd gear. I think the numbers are higher than standard because of the gearing advantage but I like it best because it shows the entire torque band from 2,500 rpm.
2ndCblFltr.jpg

The next one is with the stock air filter.
2ndThrotCbl.jpg

As I recall in drive the transmission would downshift when going to WOT below 2,700 rpm and the speed limiter was set at the stock 105 mph (4,700 rpm). The chart below is for the same engine configuration but in Drive (4th gear 1:1 ratio).
4thStock.jpg

My SOHC V6 is supposed to be rated at 205 bhp
152.6 rwhp/205 bhp = 74.4%
From what I've read rwhp is normally around 80% of bhp which means my stock engine output (with 150K miles) was 5% less than if it were new.
 






I had around 13 pulls on the dyno with various configurations of intake, throttle linkage and selected transmission speeds. All were with my stock 55 mm MAF sensor and 65 mm throttle body and stock tune. The one below is with my modified throttle linkage and low restriction air filter. It was with speed "2" selected which is 3rd gear. I think the numbers are higher than standard because of the gearing advantage but I like it best because it shows the entire torque band from 2,500 rpm.
View attachment 74123
As I recall in drive the transmission would downshift when going to WOT below 2,700 rpm and the speed limiter was set at the stock 105 mph (4,700 rpm). The chart below is for the same engine configuration but in Drive (4th gear 1:1 ratio).
View attachment 74124
My SOHC V6 is supposed to be rated at 205 bhp
152.6 rwhp/205 bhp = 74.4%
From what I've read rwhp is normally around 80% of bhp which means my stock engine output (with 150K miles) was 5% less than if it were new.

Was this on a awd dyno or did you do it in 2wd? 25% is about dead on from what I've read, even seen as high as 30% on suv or awd/4wd vehicle. Good to have a base line :thumbsup:
What's the 175rwhp listed in your signature?
 






estimated rwhp

Was this on a awd dyno or did you do it in 2wd? 25% is about dead on from what I've read, even seen as high as 30% on suv or awd/4wd vehicle. Good to have a base line :thumbsup:
What's the 175rwhp listed in your signature?

The runs were on a Dynojet. My Sport came stock as 2wd. The 175rwhp is my estimate of the power after the 90 mm LMAF, 75 mm racing throttle body and custom tune. The new baseline testing will be all of that plus the timing chain replacement, the 5R55E valve body separator plate gasket blowout repair, higher EPC pressure in tune and exhaust system upgrade. I expect the associated max rwhp to be about 180.
 






The runs were on a Dynojet. My Sport came stock as 2wd. The 175rwhp is my estimate of the power after the 90 mm LMAF, 75 mm racing throttle body and custom tune. The new baseline testing will be all of that plus the timing chain replacement, the 5R55E valve body separator plate gasket blowout repair, higher EPC pressure in tune and exhaust system upgrade. I expect the associated max rwhp to be about 180.

Oo some reason I thought you was awd.30 rwhp gains from those mods may be a little optimistic. Guess we will see from the new baseline.

Do you have cams or plan on doing anything to the motor internally?
 






internal engine mods?

. . . Do you have cams or plan on doing anything to the motor internally?

At this time I'm not planning on any internal engine modifications. As I stated earlier in this thread, my goal is to increase low and mid-range engine speed torque to improve my daily driving pleasure. I'm not aware of any available off-the-shelf mods that will do that. Originally, I planned to convert to the 5.0L V8 but our house/subdivision covenants won't accommodate four vehicles - my wife's Highlander, my Volvo turbo wagon, and two nonfunctional Explorers (donor & Sport) for an extended period.
 






I just installed my large pulley, and my M90 with the coated rotors and it still has tons of bottom end. A pleasure to drive. I'm sure going wot will not show great performance, but for driving around it is fantastic. Your setup is going to far exceed what your looking for.

Also, your post on setting the idle is something that we should all do before asking James to make adjustments to idle. I wasted his time and mine trying to get idle right. I did the procedure you posted and its a night and day difference. Thanks for posting that.
 






Alternator interference?

After removing the A/C refrigerant manifold I could get a better idea of clearance issues. In the photos below the main intake is resting on the upper intake manifold.
Mock2a.jpg

However, it looks like there may be a clearance issue with the alternator.
Mock2b.jpg

I may have to use a 45 degree reducing elbow and another 3" diameter 45 degree elbow cut to fit.
 






I'm betting you are right. There will be a few small compromises along the way. At least you will have plan b ready.
 






Alternator to hood clearance

There is 3 3/4" to 4" of clearance between the hood and the alternator case depending on the angle.
AltClear.jpg

Unfortunately, the B+ terminal boot and cable stick up 5/8" from the case. I've been thinking about replacing my alternator with a higher output unit with the same case size. I wonder if I can find one with a rear instead of side B+ terminal.
 






The OHV alternator has the rear connections. The 302 and SOHC use that same housing with the top terminal. You might be able to alter that wire connection a little to gain 1/4" or so of space.
 






OHV V6 alternator

The OHV alternator has the rear connections. The 302 and SOHC use that same housing with the top terminal. You might be able to alter that wire connection a little to gain 1/4" or so of space.

Thanks for the info Don. According to nitrodude who installed the OHV style there was very little room for the 1/0 cable he used at the rear post. He has to remove the alternator to connect/disconnect the cable. I think I can angle the main terminal (red arrow) toward the rear and down and modify the cable support bracket (blue arrow) to drop the cable behind the alternator case and gain back 1/2" of the 4" clearance.
Altntr.jpg

I'll use the super flex stranded wire cable and run it from the alternator to the battery junction box. Since I know I can purchase a 160, 200 or 220 amp alternator in my style case I'll delay that for now and just run the cable. In the future, when I decide which alternator to purchase I'll replace the maxi fuse in the battery junction box with the appropriate size and upgrade the battery cables.
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





idle air control valve

I had hopes of using a Bosch idle air control valve (IACV) since I have one from past Volvos I've owned.
IACVBosch.jpg

Unfortunately, after researching the Volvo wiring diagrams I have learned that the Bosch IACV contains a rotary valve that is controled by a variable duty cycle opening circuit from the Motronic control module and a variable duty cycle closing circuit. The Explorer IACV is a spring loaded plunger within a solenoid energized by a single variable duty cycle circuit from the PCM.
IACV.JPG

I guess I will have to fabricate something equivalent to the IACV mount on the upper intake manifold and similar to the throttle body spacer included in the Banshee Ranger kit.
IACVBASE.JPG

The Banshee throttle body spacer is drilled to match the Ranger throttle body with a built in bypass port and the Ranger/Explorer IACV. My 75 mm throttle body has no bypass port and the bolt pattern differs from the Ranger throttle body. Also, I want to mount the throttle body in the 45 degree intake leg to have room for the throttle and cruise control linkage.
 






Back
Top