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Windsor in Washington
I have a high-miles ’92 bronco with a 351W EFI engine, AOD tranny and electric shift four-wheel drive. The truck has 31x10.50-15 tires. The exhaust has been changed from the cat-back single pipe. I plan on rebuilding this engine in the near future and would appreciate your input. I plan on boring the engine .030”, balancing it and installing a mild RV type cam. I need to be Washington state emissions legal but would like to achieve better fuel economy and increased power for pulling, passing and running unimproved roads.
Gary Smith
Vancouver, Washington
You’ve got a good start on a good plan. You didn’t specify what type of exhaust system you installed, but it’s a vital ingredient in the economy/performance equation. An emissions legal single cat back system can work well in this instance as long as the muffler is a low restriction type. The pipes should be mandrill bent and the pipe size should be in the 2.5-3-inch range. Because of the high miles, you might consider a cat replacement, perhaps with a larger frontal area high performance cat. Headers are another good idea, such as those from Edelbrock or Magnaflow. Next step would be a chip replacement, such as Hypertech’s Power Module. It’s CARB legal, so you’re safe with the emissions guys. You might also consider replacing those high-miles injectors with OEM replacements so you start out with good squirters. Incidentally, a high-flow, low temp thermostat (180 degrees) is a benefit as well and it works well by reducing the engine’s tendency to ping, plus giving your truck a cooling reserve for hard work. Finally, a low restriction, cool air intake will add a bit of power as well. You may not find a dedicated cold air intake system for a truck as old as yours, but by keeping the front air duct connected and going to a low restriction air filter, you’ll get a nice gain. With these items combined with a quality rebuild, you’ll get a good boost in power, a bit more economy and no cranky manners.
Dodge Dually Dilemma
I recently purchased a ’99 dodge Ram 3500 Dually with a Cummins and 3.55:1 gearing. It comes with the factory with 215/85R16 tires. Besides asking why such dinky tires were put on this truck, I wonder if I can upgrade to 235/85R-15 tires without causing problems with the electronics. I’m getting conflicting reports. Can you help?
Marshall Carlton
Greybull, Wyoming
Well, the 235s would be giving you about 1.2 inches more height, so it would throw things off a bit. I doubt it would be a huge problem, but there’s a good answer. First, check with your Dodge dealer to see if they can reflash (reprogram) your truck’s ECU for the 235s. If similar trucks were available with the bigger tire, this should be an easy no-brainer. If they get hinky about that, some of the aftermarket programmers may do it. Check out Hypertech’s Programmers and I know Edge Products has such a unit on the horizon and you will be able to program new tire sizes yourself, as well as some hefty engine power increases.
Ford IDI Turbo Diesel Quest
In your recent diesel article, you mentioned upgrades for the ’93-94 7.3L IDI Turbo Diesel. I have had a difficult time finding upgrades for this engine. Any details in describing some of the upgrades would be greatly appreciated.
Victor De La Rosa
Via e-mail
Victor, the 7.3 IDI is one of the unsung heroes of the Ford diesel world. As I said in the article, it was deliberately detuned so as not to compete with the upcoming Powerstroke intro. If you want a bolt on 27hp and 33 lbs-ft of torque, you need look no farther than Gale Banks Engineering. Beyond that, you could go with a Bully Dog propane injection kit, which adds a big hunk-o-performance (at least 50hp on your engine I would guess) and is pretty universal. You could do either or both on your truck, but I’d strongly recommend both. The factory exhaust on your truck is one of the major impediments to performance and needs to be swapped out. With both items, you’d be faster and more powerful that stock first and second generation Powerstrokes.
XJ X-Factor
I recently bought an ’88 XJ Wagoneer to accessorize but I’m not really sure where I can begin. It has the 4.0L, AW4 auto, NP242 Selec-Trac and D30/D35 diffs. The type of wheeling I’m planning on doing isn’t going to be very intense, mainly old roads for camping fishing and hunting. I’d like to make sure everything is right the first time so I don’t have too many surprises later to bite me in the butt. My daughter will be riding with me and I want it to be safe for her.
Chris, West Virginia
Well, you’re starting off with a good platform, Chris, and one that can combine safe, streetable mods with good trail performance. Your biggest limitation will be the amount of tire your Dana 35 axle can handle. In my opinion, that’s a 31x10.50-15. Because you plan mild ‘wheeling, I’m going to recommend stuff with those tires as a starting point. First off, you’ll need about 3 inches of lift to fit them, with the tires mounted on 15x8 wheels with 3.75 inch backspacing. I’d recommend looking at the Rubicon Express 3.0-inch Super Ride kit with rear springs. It gives you the clearance, good articulation and a great ride. For gears, you need at least 3.73:1. A set of 4.10:1 cogs would be better for performance on and off the highway, but you might lose a little economy on the highway. As for lockers, if you want streetable, I’d strongly recommend an on-demand locker like the ARB or the Ox for the rear of your rig. Both offer full transparency for the street but 100 percent lockup for max traction on the trail. You can combine the Ox or the ARB with Genuine Gear’s Super 35 axle kit, which gives you a beefier axle (30 spline vs 27 spline). A Super 35 kit is also available in combo with a Detroit Locker. ARB makes a very needed and useful bull bar to which you can mount the winch of your choice, in about an 8,000 pound capacity. Slip yoke eliminator kits are available from Rubicon Express, and others, in case driveshaft angles become a problem.