munyanb

I have a 97 grand Cherokee that has around 180 k on it and it's got some bangs and bruises. I have been on here but my job really took me away from doing anything for a few years.
What I want to do is get a 3.5 " kit from iron rock off road, not sure whether to go with foundation series or the next one up. Any advice on this issue? The next kit up from the foundation series includes a double shear drag link, but is that really necessary? I also plan on going with some gas shocks , probably the bilstien.
I already put a super turbo muffler on it and a walker high flow tail pipe. My cat decided to break off in the front so I need a new one of them, but I am going to get headers as well. I found some called ATP challenge that run about 170 at summit with hardware, but I found some on amazon as low as 120 and they look the same. I believe the ATP's are made in the USA. I haven't really found a good cat yet but I found some cheap ones for around 50. So in the end I will have an affordable good flowing exhaust with a mellow sound that won't draw attention.
I bought an intake from a 99 grand Cherokee that is supposed to increase bottom end and a little mid range power.
I want this to be a daily driver or even a week end driver, but not just for offroad. I plan on getting some decent tires put on and then take on body work.
Also , I still haven't fixed that transfer case problem , I can't get it to shift into 2wd , and I used to be able to crawl underneath and put it in 2wd but that doesn't work anymore.

munyanb

I just found a cheaper header again!!!! Speed Daddy has one for 106$ but the description is vague. It looks just the same as the ATP and the other cheap header I saw. It has a 6-2-1 design, is routed different than , say a Gibson, but it says its 309 stainless, the others say stainless also but different grades. I am going to have to look at a post on here talking specifically about headers.

munyanb

OK so I found out that the ATP header is made in china and has a fitment problem on the grand Cherokee, something about the motor mount and intake I think I was told. I still plan on using a header if I can find a good used one or if I have to go Chinese I guess I will just get the cheapest one, but it is a 6-1 design. I've been looking for comparisons on headers but haven't found anything yet. I will continue looking through forums. Even a cheap header is better than stock , right?

Bustedback

The stock manifold actually flows better than you think. You definitely want the double shear track bar once you lift your ZJ, it's stronger and will tighten up the steering. Check out RYANVISION PROJECT ZJ on the YouTube, lots of stuff and good information.

munyanb

I have read posts on here with people saying the headers increased fuel mileage immensely and added better power. You say that stock manifolds flow pretty good? Is there anywhere to see actual data and dyno numbers? I have learned from a TV show that features mostly mopars that the old stock manifolds on the 60's performance models flowed just as good as any replacement header. Since then new flow technology and data collection capabilities have arisen, and you have catalytic converters, oxygen sensors and computer controlled engines.
I'm not disagreeing with you , I'm mostly curious about the real answer. I do not see any testing being done by the cheap header makers and since they are made in china do not even trust the material they are made from. I haven't looked at gibsons or the expensive ones past the price other than looking at their design that is totally different than the cheaper ones. Gibsons and the others seem to put different cylinders together and bring them all to the collectors in a pattern that seems like it would help scavenge the exhaust ports by using the firing order. That's just to much money to be spending for the reward unless I really wanted to go all out and I had money like that just to **** away. Then of course theres the shorty design that really wouldn't benefit a jeep anyway, at least not mine, I don't plan on racing with open straightaways to run the RPM's up high enough to use the headers gains, unless I get stuck in deep mud and need the higher rpms to get through. But then I hope ten horsepower doesn't make or break me.
That is something to think about , just keeping the stock manifold, but like the intake manifold from the 99, does the 99 and newer exhaust manifold also add some power?

Bustedback

I read the info in JP magazine. An aftermarket header will flow better than the stock one, but the gain isn't enough for me to pay for a new header and install it. Maybe if mine were to crack I would consider a header. The 99 and later had cast iron manifolds, I imagine the tubular manifold flows better. An exhaust system flows only as good as its restrictions, that being the catalytic converters and muffler. On the flip side, if the exhaust is too free flowing you may lose low end torque.

munyanb

I like the facts at the bottom of your post. Especially the crank sensor one. I have ran into that a few times on different Chrysler engines. Once I changed 4.0 liter engines from a Comanche into a Cherokee. They were different years with different flex plates on them. That engine would backfire and sputter but not start. That was an embarrassing oversight. Had to change the flex plate with the engine still in it , just separated everything enough. Then I figured out about the offset pattern on the flex plate holes and crank. It was a learning experience for sure, lol

munyanb

So I guess I will stick with the stock manifold , but what would you suggest on the cat? I'm pretty sure the cat is rusted off in the front and not the front pipe. A better flowing front pipe would help some and possibly a high flow cat? Or is there really any improvement that can be made to the front pipe? I would rather spring for the bilsten shocks and the drag link than something that doesn't really do anything. I know I definitely want a gas monotube shock for handling , as I love to offroad but honestly most of my driving will be on the street. That brings up another issue about tires. I love a good buckshot or swamper, but on highways they would wear out fast and not handle so well. But I want to have decent grip for when I do escape the street. Michelin has a decent all season/all terrain tire, and others do as well. Anyone got any suggestions?

Bustedback

I really can't give much of a recommendation on cats. I have heard good things about Magnaflow. As far as tires go I'm just running some inexpensive Kenda Klevar mud terrain 32-11.5-15s, they do pretty good and they're a bargain.

dave1123

I just wanted to add your '97 4.0 makes 185 hp. The redesign in '99 with larger head ports, cast exhaust manifold, and slotted water pump impeller only gained 10 hp! Don't expect a lot from the 4.0. Even changing the cam timing to make max torque at 4000 instead of 3000 didn't help it any.

Bustedback

Yeah, if you wanted power you should of gotten a V8.

munyanb

That 185 HP that it makes is pretty good. It's usable power. I have towed a mid 70's international scout with that jeep and it almost didn't know it was there. I mostly want to optimize the engine. I am not sure I like the V-8 for them , I actually think the 6 is better for a jeep. But yeah I definitely see what you are saying. It's not going to be a mud bogger or an all out race vehicle. Just a nice jeep to play around with and drive. I will be in some mud and trails for sure though.

Bustedback

So far I have changed the intake manifold to the 99+ manifold, swapped in a set of 703 injectors, moved the IAT sensor to the air box, complete tune up with the ACCEL kit from Summit Racing, got rid of the mechanical fan in favor of a Taurus electric fan, and installed a glass pack muffler. The fan swap was the best bang for the buck mod so far, but even with all of the other stuff I don't feel much difference.

munyanb

I have a dual fan setup from a dodge intrepid. Not sure if I got the relay from it but I did get a lot of the wiring. How would I go about wiring this fan up to work? I'm not sure what type of sensor to use or even where it should go. Could I just use something from the temp gauge? And would using the temp gauge even be a good way to set the fan up? It usually gets it's reading from the block , would the fan coming on when the block gets warm enough be the right timing? I guess it would be close since the hot coolant would open the thermostat and it would flow to the radiator.

Bustedback

I got a relay/controller from Amazon for thirty bucks. Super easy to install and set up, it works flawlessly.