Renix Head and MPFI on 258 Block?

[dhughes]

Ok, so all I want to do is get my '86 CJ legal to drive on the road here in CA (had to move here to stay married, and yes she's worth it).

I found a donor 90 XJ and have pulled the harness, ECU, manifolds and head. I have read the other topic on putting a 91> head on a 258.

What I couldn't find in the forum (and haven't pulled the CJ apart yet) is are there holes/ports for the coolant temp sensor and knock sensor in the 258 block, or do I need to start over?

[4.whoa]

I don't have an answer for you, but why not use a 91+ HO? With the renix you'll need to run the egr and all the crap that goes with it. HO would be neater/simpler and its better power.

[dhughes]

Because it was free and I don't have any money to spare.

[stroked'73]

Free is a good reason!! Mine's renix for the same reason, and I think the power difference is small and only at the upper end. (better flow).
To your question - there's a coolant sensor on the renix head - drivers side in the rear, next to the back head bolt stud. You can also pull off from the t-stat housing if you swap in one that has the port - the renix doesn't but the H.O.'s interchange. The knock sensor on the renix block is where one of your engine mount bracket bolts go - the drivers side and I think it's the rear one. So you probabaly can't put it there, but there might be other bosses not being used that you can tap to accept the sensor - I know there is two or three bosses for p/s bracketry toward the front - you could modify the bracket to just use one less bolt there and tap it out to fit the knock sensor. I don't think it's too crucial where you put it - I think jeep put it where it is because the boss was already there. (The 4.0's use different mounting bosses for the engine mount brackets, but the 258 holes are still there).
Is there a way to eliminate the sensor altogether or trick the circuit into thinking it's good? Then you wouldn't have to worry about the computer retarding your timing when you don't want it to. Just a thought but might be worth searching here and on the net if folks are able to eliminate or "trick" the sensor.
Good luck, hope this was of some help!!

[dhughes]

Thats great news...Thank You!

[dhughes]

So I actually talked to Hesco today. Turns out that they no longer support the Renix system, no crank sensor etc.

Any one need a 1990 4.0 L mostly disassembled?

[yuppiexj]

Location????

[dhughes]

Sacramento CA

[yuppiexj]

2750 miles too far for me.

[4.whoa]

Is there a way to eliminate the sensor altogether or trick the circuit into thinking it's good? Then you wouldn't have to worry about the computer retarding your timing when you don't want it to. Just a thought but might be worth searching here and on the net if folks are able to eliminate or "trick" the sensor.
Good luck, hope this was of some help!!

I have a '87 that i've run for 2years with the knock sensor zip-tied away from the block.I had the head milled for comp while it was rebuilt (the head)and wanted to see if it would knock.
Well, it didnt........... but the rings started to blowby so... Point is it did run just fine, and as long as you listen for "pinging" it will work/run.