Question: I have a '95 Ford F-150 shortbed with a 300 straight-six and five-speed. I've already purchased a 6-inch suspension lift and reworked the interior a bit. I want to swap the 300 for a rebuilt 429 big-block with the four-speed. I am not planning on a power-hunting rebuild, just a refreshening of the engine.
1. Can I buy engine mounts for this, or will I need to fabricate them?
2. Will I have to use a different transfer case? If so, will the one I was using behind the 429 work ('79 Bronco transfer case with 351M)?
3. Will I need to get different driveshafts?
If you guys could point me to a Web site or something I'd be eternally grateful! The magazine is fantastic-keep up all of the great work.
Rob Jonesvia fourwheeler.com
Answer: Sounds like you're building a really nice truck. Sure, there are pre-made motor mounts, and they are available from several sources. One that comes to mind is Advance Adapters (800/350-2223, www.advanceadapters.com), which has the proper frame mounts under PN 713224 and the rubber mounts under PN 713014.
To mate the four-speed transmission, you're going to need a bellhousing from one of the same family of engines-the 351M, 400, 429, and 460. I am not sure, from your letter, if you already have the four-speed coupled to the Bronco transfer case (which should be an NP205) with a factory adapter. If not, you're going to be better off if you can find a donor truck that has both the transmission and a 205 transfer case already mated than to buy the transmission and then buy an aftermarket adapter.
Yes, most likely you're going to need new driveshafts of the proper length, especially with the lift that you plan.
Question: How accurate are those electronic readouts that new vehicles use regarding fuel mileage, and how in the heck do they work?
Answer: These readouts have been out for quite some time now, and in fact, my own 11-year-old Grand Cherokee has one that is quite accurate. It was a pretty simple add-on for the vehicle manufacturers. The electronic control module already had most of the information it needed as it adjusted fuel flow to match speed and to measure the miles traveled. It adjusts speed by controlling the time and the width of the fuel pulses from the individual injectors. Some simple and very fast math (well, simple if you're a computer), and you can figure the given amount of fuel that passes through each injector in a given time period under each driving condition. Now it throws in the miles traveled during that time period, and bingo, you have current fuel mileage, average fuel mileage, and miles left on the remaining fuel.
Question: I have a '92 YJ with a tired 4.0L, while in my garage I have a '90 4.2L block that I was thinking about rebuilding. The problem is that I want to keep my fuel injection. I've heard that you can put the head of the 4.0 on the 4.2, but what about the EFI? Isn't there a crank positioning sensor on the 4.0 block?
Answer: This is a pretty common swap, and while I haven't had any hands-on experience with it, I have been told it's pretty simple and well worth the effort. It's a basic bolt-on for any 4.2L built before 1981. It seems that the 4.0L head uses 1/2-inch head bolts, and the 4.2s (starting in 1981) use smaller 7/16-inch head bolts. The deal here, as I understand it, is that you have to drill and tap the block for the 1/2-inch bolts, then use the 4.0 head gasket. There are some problems in mounting the 4.2's power-steering pump to the 4.0 head, but with some modifications to the bracket, it seems to work just fine.
For the fuel injection to work properly, you do need a pick-up sensor. You can buy a special bellhousing from Advance Adapters or use a special wiring kit from Hesco (205/251-1472, www.jeepers.biz) that uses a new dampener and puts the sensor up front.
I believe that you also have to drill a new hole for the 4.2's temperature sending unit. Oh, and this is really important: The No. 11 bolt in the head-bolt torque pattern requires some type of sealer on the threads as it goes into the water jacket.