oem vs aftermarket

[907_jeep]

now i hear alot about this topic and as far as older jeeps,is it better to stick with oem or aftermarket in terms of under the hood (spark plugs ect) ? i dont wanna waste the money if it isnt gonna make a diffrence or make it run worse then it does..

[bigjim350]

Most of the time OEM stuff is better. However, I always buy whatever is cheapest, and my stuff still runs fine.

[907_jeep]

so plat plugs and msd complete ignition is just waste of money? coldair intakes throttlebody spacers? kinda pointless?

[bigjim350]

In my opinion, I would stay with OEM plugs on a stock motor. The MSD stuff is nice but wont notice a whole lot from it. Cold air intakes do offer some gains, but I dont like open element air filters. And tb spacers to me seem useless on anything that doesnt have a carbuertor. just my .02

[Mudderoy]

Yeah just my opinion and what I have read a lot of people say...

Champion plugs!

Cold air I have heard is a huge waste of money for anything you might get in gain. You'd be better off getting a snorkel. You really get cold air plus you won't hydro-lock the engine. Snorkel = $400 cold air = $200-$300? Really a no-brainer to me.

[907_jeep]

snorkel wont hurt the mpg..i mean thats alotta tube for vaccum to travel

[bigjim350]

Shouldn't have any probs with MPG. All name brand snorkels point towards the front of the Jeep. So when you drive it gives a nice ram air effect. No problems with the lenght of tubing.

[4.3LXJ]

The thing about aftermarket stuff for the 4.0 is that the long six is a lot different than a Chevy V8. There are some things that work for it and some that don't. In many ways, it is kind of a detuned engine, so fancy plugs don't work well in it. Whereas they work great in other engines. Throttle body spacers were designed for throttle body injection. On anything else they are just fishing weights. If you want cold air intakes, you can get some benefits by opening up the air box, but not if you are mudding and puddle jumping unless you can keep the water out of it. A snorkel has to be at least 3" in diameter to be a benefit to the 4.0. Anything smaller will restrict the amount of air going in to the intake.

But there are some things that will benefit the 4.0

HO heads from a pre 99 HO engine are a great idea, as well as the intake from a 99-00 4.0. Four nozzle injectors, good air filters, bored throttle bodies and a good exhaust system are also good. Some are OEM, others are aftermarket. So there is no rule of thumb.

[PolarXJ]

:dito:

[LizardRunner]

Have to agree with Steve. I have plans to build a highly modified 4.0 but, after talking with Cliff about it, I may just buy a nice stroker or build my own when the original motor finally decided it's had enough.

[907_jeep]

well more probelms persist with this ****ing jeep :/ like now my voltage meter dances whenever i turn anything on but i think i need a new battery so i neeed opinions optima vs interstate??

[hookedonxjs]

I don't remeber where I saw it but there is a jp mag article that's titled somthing like 4.0 myths and it covers all of what you want to know, plugs to tail pipe. hope that helps you.

[hookedonxjs]

well more probelms persist with this ****ing jeep :/ like now my voltage meter dances whenever i turn anything on but i think i need a new battery so i neeed opinions optima vs interstate?? Interstates spiral cell unit is made by optima. Sealed batteries are the way to go there are spiral and plate types. other brands not listed are deka xs oddessy sears platinum. I have read that the plate type are better than spiral and the brands I mentioned are industial use, you won't see golf carts at a course running optimas most use dekas. Good luck Do you know how to check your altenator? Pull off ground cable while running and if motor dies you altenator is bad.

[xj4life2]

Back to the tune up stuff for a second, in all my experiance anything other than Cheap Ignition parts in a jeep are a waste and don't run well. I use Champion plugs in mine and have had no issues at all and still can go 50 to 60k on a tune up. I do use a K&N air filter element and have removed the cone from my air box. Fancy plugs do not do well in these at all. Also O2 sensors do not use Bosche or Denso Jeeps hate them. Factory although more money are your best bet.

[msmoorenburg]

Interstates spiral cell unit is made by optima. Sealed batteries are the way to go there are spiral and plate types. other brands not listed are deka xs oddessy sears platinum. I have read that the plate type are better than spiral and the brands I mentioned are industial use, you won't see golf carts at a course running optimas most use dekas. Good luck Do you know how to check your altenator? Pull off ground cable while running and if motor dies you altenator is bad.

I wouldn't dare do that with modern cars i've seen it nuke the ecu! get a cheep old volt meter and see if is 14.4 or close too 13.6 at idle.

[hookedonxjs]

K n N style filter at auto zone by spectre for 24 bucka roos. I have one and they are just as good as K n Ns.

[907_jeep]

thanks guys iam going to buy optima just cause iam gonna be running lights and a cb and a sub and amp off it so i need some juice ...i cant mount a wiinch to my front bumper i found out today :(

[xj4life2]

Alaska and no winch that sounds dangerous.

[907_jeep]

thanks for the input i put mastercraft cap rotor and wires in it and it seems to like it but its having random dying momments and the voltage meter seems to move ALOT when i touch the brakes or turn lights on or even turn blower motor on any help would be great fellas

[Mudderoy]

thanks for the input i put mastercraft cap rotor and wires in it and it seems to like it but its having random dying momments and the voltage meter seems to move ALOT when i touch the brakes or turn lights on or even turn blower motor on any help would be great fellas

It doesn't sound like it exactly, but I remember a problem with a broken ground between the block and the firewall causing running issues for another member.

The voltage swing reminded me.

[xj4life2]

Could be ALT or Reg also but the ground strap is a great thing to check. I'd bet regulator though.

[4.3LXJ]

K n N style filter at auto zone by spectre for 24 bucka roos. I have one and they are just as good as K n Ns.

K&N has a good name recognition, but if you use too much oil in them they will foul a map sensor. AEM has better filtration by about 2% or better and is a dry filter, no oil required.