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Tunable Induction Install

Russian Roulette

In our never ending quest to raise the caliber of Bullitt #2580, we turned to popular bolt-ons to see how the car responded. In stock trim with only a conical K&N, on Detroit Speedworks MD-1750 dyno, the car put down 226HP/265.7 ft-lbs torque to the rear wheels (baseline vehicle simulation test mode).

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This article will detail the conversion of my 1990 Mustang GT from 4-lug to 5-lug for the purpose of mounting 17×8 wheels from a 1999 Cobra (this also applies to 1998 Cobra wheels and the 17″ ‘Split 5-Spoke’ style wheel). This conversion was done with cost kept to a minimum. It would have been easy to simply order an M2300-K Cobra Brake Kit from FRPP but I wasn’t ready to drop the $1,600 for the kit. This article details the conversion that retains the front discs and rear drums for budget issues.
1987 to 1993 Fox body 5.0 liter Mustangs can be easily upgraded to 5-lugs by simply installing 5-lug axles and drums from a Ranger or Bronco II in the rear and 5-lug brake rotors from a late 80’s Lincoln Mark VII in the front. This conversion will work for most types of wheels. But, if you are planning on installing a Ford OEM wheel such as the 1998 or 1999 Cobra wheel or the 17″ ‘Split 5-Spoke’ wheel then this conversion will not work for you. This is due to the fact that the Mark VII rotor hat is too tall and the dust cap on the rotor extends too far out. This prohibits the center cap of the wheel from being installed.
There are two solutions to this problem. The first is to install ½” wheel spacers behind the front wheels to allow more clearance for the dust cap. This also requires that longer wheel studs be installed on the front rotors for safety. The other solution is to replace the front spindle, rotor and caliper assemblies from the Fox Mustang with complete spindle, hub, rotor and caliper assemblies from an SN95 Mustang. Wheel spacers are simply a Band-Aid for this fitment problem, though, and that is why I chose the latter option. The SN95 assemblies are also designed with improved geometry for better steering feel and the caliper assemblies provide improved braking as well. All in all, it is a better setup and is also the basis for any big brake upgrades in the future (i.e. – Baer or Cobra brakes). It is a project of low to moderate difficulty that can be performed in a garage or driveway with basic tools by anyone with the ability to perform a complete brake job.
Parts List
To convert the rear end to 5-lugs you need to replace the 4-lug axles and drums with 5-lug units. The axles that are needed will be either off of a Ranger, Bronco II or Aerostar van.
From an ’83 to ’92 4 cylinder or 3.0L V6 Ranger/Bronco II with a 7.5″ rear end you will need two driver’s side axles. Only the driver’s side will work as the pumpkin on these rear ends is offset and the axles are different lengths (you need the longer of the two axles). It should measure 29-5/32″.
From an Aerostar you will need two of the passenger side axles from an 86 to 97 model.
The axles are all the same so they can be mix-matched (i.e. – one driver’s side axle from a Ranger and one passenger side axle from an Aerostar).
You can use the brake drums from either side of the above listed vehicles but make sure that they are 9″ drums. The 4.0L Rangers came with an 8.8″ rear end with 10″ drums – these will not work.
Prices will vary, of course, but I was able to get the axles and drums from a local “Pull It Yourself” type yard. The axles run about $20 each and the drums will run about $15 each.
Be sure to check the axles to make sure they are not bent or worn on the bearing surface and check the drums to ensure that they are smooth or can be turned to no more than the maximum diameter.
Miscellaneous items for the rear include new brake shoes, fresh gear oil, RTV gasket maker to seal the differential cover and one additional lug nut for each side.
For the front you will need one each left and right side spindles, hubs, rotors and calipers from either a ’94 or ’95 V6 or V8 Mustang. The assemblies are the same for the V6 and V8 so either will work but it must be from a ’94 or ’95. This is because the spindle was moved out about ¼” – ½” on the ’96 and later Mustangs. This will cause the wheel to stick out too far and possibly cause interference problems with the wheel well lip on the fender.
If you are getting the parts from a wrecker in a complete assembly (as I did) then make sure that they include the Banjo Bolt that attaches the flexible brake line to the caliper. This will allow you to connect your existing brake lines to the SN95 caliper since the threads are different and the Fox Banjo Bolt will not thread into the SN95 caliper. Using the SN95 Banjo Bolt is the easiest way to do it rather than connecting the SN95 flexible lines to the Fox hard lines because they are different sizes and will require adapters (and the SN95 uses two different size connectors left and right side). Just use the SN95 Banjo Bolt on your flexible line for ease of installation (they even worked with my stainless steel braided lines). I was able to get the complete assemblies for $125 per side from the wrecker.
Miscellaneous parts needed for the front include new brake pads, one additional lug nut for each side, new cotter pins (4), new copper washers for the Banjo Bolts (4) and a 0.330″ tall spacer (or washers totaling 0.330″). The last item is necessary to properly fasten the crown nut on the lower control arm ball joint/spindle connection. I will explain this in more detail in the reassembly section.
Begin by loosening all lug nuts prior to raising the vehicle. Raise and safely support the vehicle with jack stands. The jack stands should be positioned so that the suspension components hang free. You will want the rear end to hang down to ease the removal and reinstallation of the differential cover (otherwise the rear sway bar can be a hindrance). You will want the front control arms to hang down free so you can manipulate it with a floor jack during the removal and installation of the spindle(s).
Once the vehicle is safely supported on jack stands and all 4 of the wheels have been removed start by removing both brake drums (ensure that the parking brake is off). Drain the rear differential fluid by loosening (not fully removing) all of the cover bolts and pull the lower portion of the cover away to allow the fluid to drain out the bottom. Once empty remove the bolts and remove the cover. With the transmission in neutral rotate the rear differential until you see the small Pinion Rod Retaining Bolt. This bolt runs sideways into the differential. Remove this bolt and then slide out the Pinion Rod (placing the car in Park or in gear will allow you to remove this bolt without the differential rotating). Now you can push the axles inwards allowing you to remove the C-Clip retainers. With the C-Clips removed the axles will slide right out. Be careful not to damage the axles bearings or seals when removing the axles.
Start with the front by disconnecting the flexible brake line from the caliper by removing the Banjo Bolt completely from the brake line. Have a cup or rag ready to catch the brake fluid (brake fluid will destroy paint – Be Careful!). Remove the two bolts holding the caliper to the spindle and remove the caliper. Remove the dust cap from the rotor to allow access to the bearing retaining nut. Remove the cotter pin on the crown cap and then remove the cap and nut. Pull the rotor off of the spindle with the bearings.
Place a floor jack under the lower control arm and raise the jack just under the control arm so it just starts to compress the spring. Loosen the two bolts that secure the strut to the spindle.
On the tie rod end, remove the cotter pin and crown nut and separate the tie rod end from the spindle.
On the lower control arm ball joint, remove the cotter pin and crown nut and separate the spindle from the lower control arm (be sure the floor jack has the lower control arm supported to keep the spring from unseating and causing damage or injury!).
Now you can remove the two screws holding the spindle onto the strut and remove the spindle completely.
Repeat for opposite side.
Slide the new axles into the housing tubes being careful not to damage the bearings or seals. Push the axles in as far as they will go and seat them with the spider gears in the differential. Replace the C-Clips on the axle ends and push the axles back outwards to lock them into place. Reinstall the Pinion Rod. Apply thread locker to the Pinion Rod Retaining Bolt, reinstall in the carrier and torque to specification (15-30 lbf.ft.). Clean the differential housing cover and remove any silicone sealer residue from both the cover and the housing itself. Apply a ¼” bead of RTV to the cover and reinstall the cover on the housing. Replace all bolts and torque in sequence to specification (25-35 lbf.ft).
At this time the rear brake shoes can be replaced to allow time for the silicone to set up before adding new gear oil. Once complete, replace the brake drums and add the required amount of the specified gear oil.
Begin the installation of the SN95 spindles by placing the spindle/hub assembly on the ball joint on the lower control arm. Before screwing on the crown nut to secure the spindle you will need a spacer on the ball joint between the spindle and crown nut.
The reason for this is that the stud on the ball joint of the Fox cars is longer than the stud on the SN95 cars. So, when you go to tighten the crown nut to specification you will have gone past the cotter hole and the crowns on the crown nut will not line up with the cotter hole for the cotter pin. FRPP addresses this problem in their M2300-K Cobra Brake Kit with a spacer that they provide to keep the crown nut in line with the cotter hole.
Unfortunately FRPP does not sell this spacer separately (it is only available in the kit) and nobody else to my knowledge sells it either. But, I was able to obtain the height of this spacer from FRPP whom suggested I have my own manufactured. The height needed from the spacer is 0.330″ and the center hole diameter should be 5/8″ to fit on the stud. The thickness of the spacer should simply be sufficient to sustain the rigors of the suspension.
Another solution (the route I chose) is to simply obtain some 5/8″ hardened washers and stack them up to achieve the necessary height. I ended up needing 3 fairly thick washers per side.
Once you have your spacer (or washers) in place you can screw on the crown nut but do not tighten just yet.
Now fit the tie rod end onto the spindle and screw on the crown nut but do not tighten just yet.
At this point the strut can be attached to the spindle with the two mounting bolts and nuts. Torque the nuts to specification (140-200 lbf.ft.). Some manipulation will most likely be necessary with the floor jack at this point to attach the strut mounting bolts.
Now you can torque down the tie rod end crown nut to specification (35-47 lbf.ft.) and install a new cotter pin.
Finally torque down the lower ball joint crown nut to specification (110-150 lbf.ft.) and install a new cotter pin.
With the spindle now installed, place the rotor on the hub and mount the loaded caliper on the spindle. Attach the caliper with the two mounting bolts and torque to specification (70-95 lbf.ft.).
Place a new copper washer on the SN95 Banjo Bolt and insert the Banjo Bolt into the flexible brake line. Place another new copper washer on the other end of the bolt (so there is now a new washer on either side of the brake line) and screw the Banjo Bolt into the caliper. Be sure to route the flexible line so that it will not make contact with the front tire or wheel while driving and turning and then torque the Banjo Bolt to specification (30-40 lbf.ft.).
Repeat procedure for opposite side.
Once both sides are complete bleed the brake system (consult your repair manual for proper bleeding procedure).
Once the brakes have been bled the new wheels can be mounted and the lug nuts snugged up. The car can then be safely lowered from the jack stands and, with the car on the ground, the lug nuts can be torqued to specification (85-105 lbf.ft.).
Finishing Up
With the car on the ground and the steering wheel centered you will notice that both of the front wheels are pointing inward (toe-in). This is due to the different mounting points of the SN95 spindles. The car cannot be driven like this safely and will surely destroy your tires. The toe needs to be adjusted out so the car can at least be driven to have the front end re-aligned (or have the car towed). Consult your repair manual for the proper procedure for adjusting the toe (basically loosen the tie rod end lock nut and rotate the adjustment until the wheel(s) point straight forward and then tighten the lock nut).
With the toe adjusted check clearances before driving the car.
Check the clearance of the tires to the fenders. If they are going to rub then the fenders will have to be rolled to allow the proper clearance.
Check the clearance of the wheel to the lower control arm at full lock of the steering wheel. Larger wheels on an ’87 to ’90 Mustang will most likely rub at this point. This can be solved by installing steering rack limiters to decrease the turning radius of the vehicle (Ford part number N804842-S). ’91 to ’93 Mustangs have a decreased turn radius from the factory so this may not be a problem.
Finally check the clearance of the brake lines to ensure that they will not rub the tires or wheels under any condition.
With the installation of the SN95 spindles and brakes on the front of the car I have noticed improved handling and braking. The steering feels more precise and responsive especially on turn-in.
One huge bonus is that the SN95 spindles seem to have completely cured the excessive bump-steer that I was experiencing. The car no longer wanders around the road following grooves or bumps. It just feels solid. This may not be the cure for everyone’s bump-steer but it helped in my case.
The improved design of the SN95 calipers provide more clamping force and less brake fade. A huge improvement over the stock Fox brakes.
Another positive aside from this conversion is that you now have the basis for the addition of larger Cobra brakes or an aftermarket big brake kit such as Baer later on down the road. These kits require SN95 style spindle and hub assemblies to work on Fox body cars.
Total outlay for parts (including brake pads and miscellaneous parts) and labor (for turning the rotors/drums and alignment) was just about $475 (not including new wheels). All in all it was a worthwhile conversion that I would certainly recommend to anyone considering converting to 5-lug on a budget. It will be more costly than simply using Mark VII rotors but not near as much as the FRPP M2300-K kit and will still give you improved braking and handling.
* Disclaimer: I am not a certified mechanic and in no way imply that I am. This article is only published to give the reader an idea of the scope of the task listed therein and should in no way be construed as instructions for completing this task. Consult a qualified mechanic before attempting this task. Torque values and technical references listed in this article are for reference only and are believed to be correct at the time of this writing. Always verify current torque specifications prior to final tightening. Use this article and the information contained herein at your own risk.


This article will detail the conversion of my 1990 Mustang GT from 4-lug to 5-lug for the purpose of mounting 17×8 wheels from a 1999 Cobra (this also applies to 1998 Cobra wheels and the 17″ ‘Split 5-Spoke’ style wheel). This conversion was done with cost kept to a minimum. It would have been easy to simply order an M2300-K Cobra Brake Kit from FRPP but I wasn’t ready to drop the $1,600 for the kit. This article details the conversion that retains the front discs and rear drums for budget issues.

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Install Mustang UnderDrive Pulleys for 4.6L GT/Cobra

Guide to installing piggybacked underdrive pulley systems for 4.6L GTs and Cobras
Tools needed
– ratchet
– ratchet extensions
– 10mm, 11mm, 18mm sockets plus others
– torque wrench
– breaker bar or impact wrench
– harmonic balancer puller tool (place deposit at O’Reilly or AutoZone, get $ back when done)
– 3/4″ drive ratchet OR massive screwdriver
– Loc-tite Red
– high temperature silicon RTV sealer (ultra black OEM)
– floor jack and 2 jack stands (optional)
– a helper (optional)
1.) Disconnect the negative battery terminal. Just a preventative measurement.
2.) Put the car into first gear if manual, park if automatic, set parking brake.
3.) Begin by removing the Degas container’s three bolts and washers. They secure the overflow container for the radiator to the fan as well as a pedestal in back.
4.) Position a catch pan of some sort beneath the driver’s side headlight, underneath the radiator’s bottom corner.
5.) On the Degas container there is a small hose running from the container into one of the main radiator lines. Using a pair of pliers, squeeze the hose clamp tabs towards each other and gently rock the clamp away from the fitting. Remove the hose, and be prepared for a bit of coolant to seep out of the plastic nipple. * you may want to stuff a rag or towel into the crack where the nipple leaks coolant, or let the catch pan do it.
6.) grasp the Degas container by the left and right sides as if handling a package. Rotate one side of the container under the other so it rotates away from the pulley area, giving you clean access to the pulley system. On my 4.6L GT there was a plastic tab which conveniently held the overflow container away from the work area without stretching hose lines.
7.) Using a 10mm socket, loosen the water pump pulley from the water pump. It is helpful to have an assistant put counterforce on an opposing bolt with another 10mm socket tightening while you are loosening. When your bolt breaks loose, stop and repeat for the rest. Leave the pulley on with the bolts slightly broken.
8.) Remove the accessory belt. Using a 3/4″ ratchet (one of the biggies), put the bare ratchet into the belt tensioner’s hole and turn the handle in the direction indicated by the tensioner pulley. The pulley will move away from the belt, allowing you to slip it off the top of the alternator pulley at the top of the engine. Once it is off the alternator, the belt will have plenty of slack and you can remove it from the rest. ALTERNATE METHOD: if you do not own a huge 3/4″ ratchet, you can put a massive flathead screwdriver into the tensioner hole and lean into it, pressing the tensioner down and away, pulsating on the tensioner. An assistant will be able to barely and laboriously remove the belt from the alternator pulley.
9.) If you are using the alternator pulley from the new set, remove the alternator nut with an impact wrench. If you do not have one, it will not come off. Either use the stock one as I did, or unbolt the alternator, drive to your neighborhood garage, and ask them politely to install the underdrive.
10.) Remove the water pump pulley and set it aside.
11.) Now remove the crank pulley. This is what you ate your Wheaties for this morning. Use a 18mm socket on this bolt. It is NOT cross-threaded, it is conventionally threaded, just takes brute force to get it off. A long pipe or breaker bar should afford you the leverage you need to break the nut. After that, its all downhill. Remove the bolt and set it aside, retaining the large washer.
12.) Pull the crank pulley off the crankshaft using the puller tool. It is very simple to use and all the bolts you need will be in the box you rented it from. If there are not any bolts, use the ones in your pulley set temporarily. This is hard to describe how to use but it is very simple you will figure it out. The puller tool serves one function: to pull circular objects off their center bolt by applying perfect equal force to all three sides.
13.) Now the 2 main pulleys are off – water pump and crank. The next step is to bolt the underdrive crank and the stock crank together. Why? Because the stock crank pulley acts as a dampener and is needed to smooth out crankshaft operation, that’s why. Use the three bolts included in your kit to sandwich the pulleys together. Use loc-tite here. Tighten WELL.
14.) Using your ultra black gasket sealer, put a dab in the notch key area of the underdrive pulley so when you install it no oil can get out.
15.) Now slide the 2-pulley array onto the crankshaft, underdrive first. Gently work it inward as much as you can. Then insert the new longer crank bolt with your stock old washer. Use this to further draw the assembly onto the crankshaft. Torque to 60-65 ft/lbs (tight).
16.) Install the new water pump pulley and secure it using the stock bolts. Torque to ~ 20 ft/lbs.
17.) reinstall the belt. Make sure it goes on the underdrive crank pulley, not the stock crank pulley which is also right there.
18.) Position the Degas container back where it goes and bolt it down.
19.) Re-attach the small radiator hose to the Degas container.
20.) Start the car and let it idle, observing the pulleys and belt. Watch for any loose bolts on the sandwiched pulleys or a pulley spinning out of round. If everything is OK and the belt is no slipping, go ahead and take a spin. Your radiator lost a little bit of coolant, so top it off with some water.
That’s it. Be sure to re-torque the crank pulley bolt and water pump bolts a couple days afterwards to make sure they are holding their torque. Enjoy your 5 horsepower improvement!

Guide to installing piggybacked underdrive pulley systems for 4.6L GTs and Cobras


Tools needed

– ratchet

– ratchet extensions

– 10mm, 11mm, 18mm sockets plus others

– torque wrench

– breaker bar or impact wrench

– harmonic balancer puller tool (place deposit at O’Reilly or AutoZone, get $ back when done)

– 3/4″ drive ratchet OR massive screwdriver

– Loc-tite Red

– high temperature silicon RTV sealer (ultra black OEM)

– floor jack and 2 jack stands (optional)

– a helper (optional)

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SN95 Mustang Spring Install Tech 1979-2004

Aftermarket springs will dramatically improve the look of your Stang, while giving it better road handling ability. For Project Sundance, we chose the Steeda Sport Springs. The springs drop the car 1.75″ in the front, and 1″ in the rear. By doing so, it gives the Stang a slightly angled look reminiscent of the muscle cars from long ago. This install is pretty straight forward, anyone with basic knowledge of cars and tools should be able to complete it in 4-5 hours. In short, if Spreadman can do it, so can you.

*Note – All though this is a 99 Mustang, the basic instructions can or will apply to Mustang years 1979-2004 as they all use the FOX body chassis.

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Ford Mustang Speed Sensitive Volume Mod

How many times do you play with the volume cruising down the road?  Ever wish your 2001 Mustang could adjust the radio volume automatically, like so many other Ford vehicles do? Well, for pennies and an hour of your time, you can add Speed Sensitive Volume to your car.

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Mustang Mass Air Conversion

In this document, I will outline the steps to convert a speed density mustang to the MAF system. I am generating this because I felt the documentation I had to work with could be improved. This is based on my own personal experience converting my 88LX convertible to MAF and the instructions that came with the kit I bought. The color codes of the wiring are what I saw in my car and may not be the same but probably are. This document is for reference only and I accept no responsibility for what you do to your car.

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Steeda Tri-Ax Shifter for the Tremec 3650

We knew right from the start what the first modification to our Project Bullitt would be – the now infamous Steeda Tri-Ax shifter. Before the arrival of our Bullitt, we had not yet driven a car with the new Tremec 3650 transmission. We knew that this tranny would be a much improved version over the older T45. Tremec states that this is actually not a re-designed T45, but rather a new tranny designed from the ground up. Within the first 3 days of having our Project Bullitt, we put over 1400 miles on it. We took delivery of the car in Dearborn, MI and drove her home to Auburn, AL. The transmission feels great. Shifting is more precise and the gear ratios seem to work better with the car. The stock shifter included with the 3650 does a fine job, but, being the gearheads we are, we knew that we had to have an aftermarket one. We wanted more precise shifts and the less ‘cushiness’ factor.

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Recovering Your MACH 460 Speaker Covers

Have you ever wanted to spice up the interior of your Mustang, but didn’t want to paint interior pieces or spend hundreds of dollars on expensive moldings and replacement parts? Within this article I’m going to show just how easy it is for you to recover the MACH 460 speaker covers. This mod is fairly simple, does not take more than a few hours, and best of all is inexpensive. As for the results, well take a look:

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Mustang BBK Shorty Header Install

It’s a rite of passage these days. Putting Flowmaster mufflers on your Mustang, that is. In today’s market, consumers don’t just have one choice in exhaust products, which gives them the opportunity to make their Mustang sound unique. This can be done by using several different exhaust combos, shorty or full length headers, H or X pipe, using dumps or tail pipes, etc. Well, the owner of our 1995 Mustang GT project car, Jeremy, wanted to make his Mustang sound unique. Not wanting the famous Flowmaster sound, Jeremy has opted to keep the stock mufflers for now. One of the cheapest ways to change the tone of the stock exhaust is replacing the stock , restrictive headers (see fig 1). In a quest for more horsepower, replacing the stock headers is a must, especially for those Stangers with modified motors. Jeremy went out and purchased a set of BBK unequal length shorty headers from Brother’s Performance Outlet.

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