I have my 1987 5.0 EFI installed in my 48 willys truck and all wired and now need to fabricated my exhaust. Do I need those O2 sensors in the system or will it be a problem to just delete them? I am using the EGR system, MAP,but not the air pump. Smog test is not a issue.
you dont need them you can use an o2 simulator. you wont get proper air fuel readings by the computer. but it sets base fuel and timing settings so they wont go crazy and run like shit by any means. but if you want it to perform well and get proper readings you need a cat, how cool does that sound(not very). I would Use a wideband O2 sensor for your front the computer can control everything through a wideband very well. as for the rear just delete it. I do believe its a speed density motor, and it has no Mass Air sensor. If thats the case you REALLY REALLY need a wideband. the only way speed density can tune air and fuel is by the Map sensor and is aided by the o2. you will experience a little more power when using it because it can give accurate readings and communicate with the computer better.
This is a EEC system with just one 02 sensor in the front of the converter on each side. I am using the stock 87 5.0 HO computer. I think you are referring to a OBD II system? I really don't want them cats under this thing.
You won't want to use simulators, those are usually intended for systems with a 2nd downstream O2 that verifies the catalyst is working properly so it can trigger the engine light when it goes bad for pollution prevention purposes. Simulators allow the converter to be removed without triggering the light. 87 5.0 is a proper mass air flow system that needs the variable O2 reading to run right. All domestic O2s of that era are the same size, just get a weld-in universal bung but good luck finding em at a local parts store. Even NAPA counter people look like a dog with a high pitched noise when you ask for one. Put em up in the headers so they get hot faster. O2s don't read properly til they're up to temp.
You need them or the system won't go into closed loop. This will cost you mileage and efficiency. O2 sims are only intended for post-cat O2s on OBDII cars. (and which were were used on a few just prior to OBDII)
Prior post was correct on asking for one at A/Z or typical parts store, I got mine at a muffler shop $2.00 , getter as far upstream in the exhaust that you can!!
If you can't find any bungs locally you can make your own easily enough. All you need to cut the threads is a tap for the old, larger 18mm spark plug holes, same size and thread pitch.
yea we put them in my dads and the engine runs so much better smoother and everything so i sugest you do
We had a hard time finding the bungs when converters first came out. We made our own by slicing a metric nut in half on a band saw. I'd buy 6 nuts, slice them in half and have 12 bungs. They are easier to find now. Our local speed shop had them too. On my 1990 5.0 they were mounted up front right behind the manifold head pipe connection. I got after market direct replacement sensors instead of the universal-fit-all type. They plug right into the stock Ford harness.
I do powertrain testing for a living and for our various setups we use a local shop called Auto-Cycle-Marine. The have the O2 bungs and various other exhaust pieces as well as a ton of other parts for numerous uses. http://www.hosenow.com
Yes you need them. As for the bungs, if you cant find them buy sparkplug anti foulers from the help section of any parts store.
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