Topic: Recent mods with a few questions

[kevinebass]

Hey guys hope everyone had a good 4th.  I think I am still paying for mine.  Too much drinky drink.

Ok so I got my son a 92 wrangler with the 4 banger for his first vehicle.  It is in really good shape with 159k miles.  Lots of miles but runs pretty well.  it was bone stock up until we got it.  Here is what we have done so far.

4.0 throttle body
electric fan (question on wiring to follow)
AEM intake
New plugs, wires, rotor, cap, coil (question for plug gap to follow)
dynomax cat-back exhaust (question to follow)

Okay,
here are my questions.

1.  can't find an ignition hot in the engine bay to wire the fan into so it will stop when the key is off.  Any suggestions with location of wires please?

2.  The store told me to gap the plugs at .035.  The plugs I pulled out of the engine were .050.  Which is better?

3.  If for some odd reason my cat was hollowed out or replaced with a straight pipe would that help highway speeds?  Would it run bad due to O2 sensor reading rich?

Thanks alot guys.  Appreciate the help.

Kevin

[Jeffy]

Hey guys hope everyone had a good 4th.  I think I am still paying for mine.  Too much drinky drink.

Ok so I got my son a 92 wrangler with the 4 banger for his first vehicle.  It is in really good shape with 159k miles.  Lots of miles but runs pretty well.  it was bone stock up until we got it.  Here is what we have done so far.

4.0 throttle body
electric fan (question on wiring to follow)
AEM intake
New plugs, wires, rotor, cap, coil (question for plug gap to follow)
dynomax cat-back exhaust (question to follow)

Okay,
here are my questions.

1.  can't find an ignition hot in the engine bay to wire the fan into so it will stop when the key is off.  Any suggestions with location of wires please?

2.  The store told me to gap the plugs at .035.  The plugs I pulled out of the engine were .050.  Which is better?

3.  If for some odd reason my cat was hollowed out or replaced with a straight pipe would that help highway speeds?  Would it run bad due to O2 sensor reading rich?

Thanks alot guys.  Appreciate the help.

Kevin

#1  Run the fan off a relay and have the switched side run to the dash and then tap off the fusebox.

#2 .035" is the stock gap.  If you can run a larger gap without pinging, then go ahead.  Since I'm running aftermarket Performance Distributors cables and coil, I run my gap at .065".  If it pings then reduce the gap.

#3 well, no cat is better then a stuffed up/blocked cat.  Although, I'd run a cat so that you can keep what lower end torque you have at hand.  An aftermarket hi-flow like the Carsound, I'm using was cheap ($114), a lot lighter, flows better and is legal.

[Castr8r]

#1 - what Jeff said.
#2 - My best luck with AMC/Chrysler engines has been with Champion plugs; try gapping to .040" to start with, more if it works.
#3 - When my exhaust system was rebuilt two years ago, I put on a cat that you could see thru that cost $85.  That cost is negligible for the benefits (environmentally correct) and has no notieable restriction.  Hope this helps.

[Bounty Hunter]

The catalytic converter (or lack thereof) is downstream of the o2 sensor and will have no effect on its reading.

[kevinebass]

Thanks alot for the replies guys.

Here is what I ended up doing. 

I bought the Dynomax cat back system from Summit ($140)

It was supposed to be a direct bolt-on but lets say it wasn't.  Had to have a 1 foot section welded in between the muffler and the cat.  I decided to leave the cat on and not do anything to it.

Now there are no air leaks that I can find but when I am up around 3000rpm and I let off the gas I get the sputtering sound almost like a backfire or something.  I always thought that was caused because of an air leak or something along those lines.

Wanted to let you guys know that I did the 15-20 tank conversion this weekend.  It was easy minus the bashed up forearm.  I didnt' drop the tank either, used a lift though.  Probably couldn't do it without the lift.   Thanks again.

kevin

[jfrabat]

Thanks alot for the replies guys.

Here is what I ended up doing. 

I bought the Dynomax cat back system from Summit ($140)

It was supposed to be a direct bolt-on but lets say it wasn't.  Had to have a 1 foot section welded in between the muffler and the cat.  I decided to leave the cat on and not do anything to it.

Now there are no air leaks that I can find but when I am up around 3000rpm and I let off the gas I get the sputtering sound almost like a backfire or something.  I always thought that was caused because of an air leak or something along those lines.

Wanted to let you guys know that I did the 15-20 tank conversion this weekend.  It was easy minus the bashed up forearm.  I didnt' drop the tank either, used a lift though.  Probably couldn't do it without the lift.   Thanks again.

kevin

I have a Gibson Cat Back, and I also get the sputtering when downshifting.  Always thought it was normal.  And I also got a bashed up arm on the conversion when I did it about 2 years ago!

[blacknblue]

Not to hijack the thread or anything but ever since about 2000 miles after I installed the Banks header and monster exhaust there recently has been some pinging.  Sounds almost like a diesel engine.  Occurs mostly at idle or low rpms.  Looking back, I installed a firepower ignition with the screamin demon coil...ran my plugs at .065  I am going to regap down to .55 and see if that's it.  Quick question...is there any harm done to an engine by running a header and free flowing exahust while not moddifying the intake? 

[jfrabat]

I dont see how that could damage the engine...  Maybe you cannot get all the power you could, but I doubt you will damage the engine.

[Jeffy]

Pinging as in engine knock?  Or popping as in exhaust as you're downshifting down a hill?

I'd imagine it's the later.  If that's the case, I'd make sure your header is seated properly.  If there's a leak it will pop.

[blacknblue]

     Pinging as in Engine knock.  Sounds like an normal engine to me,  nothing extremely apparent, but I drive it every day and only I notice the subtle changes in sound and power.  It is only heard under load...can't really hear it in nuetral...put it in drive and you can hear a little knock like rod knock.  In park when the clutch fan kicks in it will knock a little. 
     I replaced the overgapped Boch plugs as a precaution with a set of E3's set at the manufactures gap.  The engine now has some more pep than before...I like these plugs.  Engine still has a slight knock.  Only thing I can think of is this...I experimented with higher octane a few weeks earlier.  It was Amoco Ultimate 91 or 93...supposed to clean your engine and all that.  I wanted to run a tank of it and see.  I liked the power increase but decided against using it daily based on cost.  Could higher octane have created this knock?  Perhaps not having the engine calibrated for higher octane such as a chip or programmer for air/fuel ratio and timing? 
     I am going to try disconnecting the battery to reset the ecu and see what happens.  F**** premium   I have already ran a tank with Gummout all in one fuel additive and it still exists.  If anyone has a clue...help me before I resort to buying a louder stereo.

[jfrabat]

The octane is an indication of the fuel's resistance to be ignited by pressure (also known as dieseling).  The higher the compression ratio, the more likely a regular gas will ignite before the spark plug goes off (because of the pressure), so this is why cars with higher compression ratios need to run higher octane gasoline. 

If you put a higher octane gasoline in an engine that is rated for less octanes, all you are doing basically is wasting your hard earned money, as the less expensive fuel would work just as well.  Other than that, the higher octane will have no other effect.

Anyway, that is what I remember from when I worked for Esso (Exxon Mobile) about 15 years ago!  I am sure if I am mistaken in my understanding someone here will correct me...

Felipe

[blacknblue]

     Thanks Felipe.  I totally agree with you about high octane for my jeep being a waste of hard earned money.  I am gonna say that the noise I am hearing is just a sound from the header as the muffler has deepened it's note a bit more.  I have heard that mufflers will get louder /deepen after time.  Took another jeeper for a ride and we agreed it was nothing.  I still want a louder stereo regardless.   

[jfrabat]

Just make sure you buy a Sony; that should help insure my paycheck and thus my future investment in my YJ!