engine replacement advice request

[WILDHOBO]

Good luck - the exhaust "manifold" is part of the head. No manifold to remove. Otherwise, I bet there'd be a huge aftermarket for headers for the 3.6

If they wanted, I'd bet they could squeeze 1 or 2 HP out of these with an exhaust port redesign and some head mods.
But the exhaust design on these is extremely short, pretty equal length, and very short to the pipe.
Not a lot to gain here - unlike the free-flow exhaust of the 1970 AMC, and the dogleg exhaust port. They gained a lot of HP just by reshaping the exhaust port and smoothing out the exhaust manifold flow.

I was joking. No room. I had my 304 heads ported and had headers on it. Combined with flat head pistons and 10.5:1 compression, it was putting out around 325hp. Doesn’t sound like much, but cj7’s are light.

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[ShadowsPapa]

I was joking. No room. I had my 304 heads ported and had headers on it. Combined with flat head pistons and 10.5:1 compression, it was putting out around 325hp. Doesn’t sound like much, but cj7’s are light.

Back then, and with a 304, that's respectable - over a HP/cube.

 

[WILDHOBO]

Back then, and with a 304, that's respectable - over a HP/cube.

It was very fun to drive, and sounded even better. No cats, just headers and two flowmaster mufflers. I wouldn’t do that again from a legality standpoint, but it didn’t have cats when I bought it all broken down and barely running, so I had a little less guilt.

 

[Lost1wing]

Very early on, in fact, still in HS, I got the reputation as a "troubleshooter". I took on jobs where others had failed to actually resolve the problem.
Our high school auto instructor saw that in me and groomed me for the contest, and challenged the heck out of me by deliberately making things not work to see how well I could figure them out. I loved it. It's how I got my second shop job, my first out of college - walked into a shop where the service manager was getting very frustrated with a Ford he was working on (he was a "Ford rules, everything else sucks" sort of guy. Bad time to walk in and look for a job...... LOL
He had it on the scope and had been struggling with it for a while. We chatted a bit, then he said take a look at this engine, the scope, and tell me what's wrong.
I did - checked some things out and saw something in the pattern and pointed it out and gave him a suggestion. It worked - he said "you start next Monday".
I didn't even need to use the letter I had from Plymouth Corp stating that if I walked into a dealership looking for a job they should strongly consider me.

Fakebook groups drive me nuts - "why is my batter dead" - answers range from "probably the regulator", to "you need to replace the alternator" to "it's the engine to chassis ground" to a few other crap guesses tossed in for good measure. No one even says "have you checked the voltage at the battery with the engine running" or "what's the battery voltage with the engine off", none of that. It's right away into stating it's this or that part, to instantly suggesting replacing parts. (in one case, the battery was fine, the starter was toast!)

(Happens here, too.......)

I was the go to guy at work my self. I was actually on the troubleshooting team and one of the go to guys on that crew. I'm going to have to sit down with you one day and have a beer. I hardly drink any more but I could make an exception.

Management called me into the office one day and they closed the door behind me. I thought I was in trouble when I saw the VP in on the meeting. All they wanted to know is how I function and could I train others. I said that I started out fixing things out of necessity when I was young. Most of the people we had working with us were nice guys and very smart, but not great mechanics. Aircraft work isn't that complicated but to isolate components, it takes time and energy to open panels to gain access. Most are too lazy. Without trying to get anyone in trouble, I said the guys just have to be willing to get dirty and get busy. In reality, we only had a handful of guys that could troubleshoot. The rest ate Crayolas in kindergarten.

 

[ShadowsPapa]

I was the go to guy at work my self. I was actually on the troubleshooting team and one of the go to guys on that crew. I'm going to have to sit down with you one day and have a beer. I hardly drink any more but I could make an exception.

Management called me into the office one day and they closed the door behind me. I thought I was in trouble when I saw the VP in on the meeting. All they wanted to know is how I function and could I train others. I said that I started out fixing things out of necessity when I was young. Most of the people we had working with us were nice guys and very smart, but not great mechanics. Aircraft work isn't that complicated but to isolate components, it takes time and energy to open panels to gain access. Most are too lazy. Without trying to get anyone in trouble, I said the guys just have to be willing to get dirty and get busy. In reality, we only had a handful of guys that could troubleshoot. The rest ate Crayolas in kindergarten.

My college class for automotive started with 30.
18 of us finished.
In the beginning those other 12 were so sure they were going to be the best, could handle it, knew what they were doing. Then came having to troubleshoot or explain how things worked, math and so on.
i never did hear of any of them working in any shops I knew of. In fact, I can't say I heard of any of them actually going on into that line of work.

 

[Stan H]

LOL - that's funny. CAI - HAHAHA.

Exhaust - maybe with good headers tuned for that specific engine.

Saw a dyno report from a guy building a nice performance V8 and ironically, he INCREASED HP by a large amount by swapping the brand and type of headers from large tube to SMALL tube headers (and a different Edelbrock intake manifold).
He said the header change alone gained several HP

I uh oh uh uh huh ?? okay give up what is CAI

 

[Charles 236]

I uh oh uh uh huh ?? okay give up what is CAI

CAI is an acronym for Cold Air Intake. What it really is is a sound effects kit. Plenty of noise, no appreciable difference in power.

 

[Stan H]

CAI is an acronym for Cold Air Intake. What it really is is a sound effects kit. Plenty of noise, no appreciable difference in power.

Oh okay , brain not working this early. I think the supercharger are the biggest power makers for these but such a gamble in terms of early demise of the engine.

 

[Stan H]

Well , it would be a combination of increase in and increase out. I wasnt trying to say just a cold air intake alone was gonna do something
I aint that dumb.

 

[WILDHOBO]

CAI is an acronym for Cold Air Intake. What it really is is a sound effects kit. Plenty of noise, no appreciable difference in power.

And these jeeps have cold air intakes from the factory with the duct feeding the air box.

I will say that there are aftermarket air boxes that actually serve a purpose. A gain in horsepower, almost never. But I have one from Corsa that genuinely filters way better, without flow restriction over factory. For all the fine particle dust mine sees, I like it very much.

 

[WILDHOBO]

Well , it would be a combination of increase in and increase out. I wasnt trying to say just a cold air intake alone was gonna do something
I aint that dumb.

That you are not.

 

[Lost1wing]

My college class for automotive started with 30.
18 of us finished.
In the beginning those other 12 were so sure they were going to be the best, could handle it, knew what they were doing. Then came having to troubleshoot or explain how things worked, math and so on.
i never did hear of any of them working in any shops I knew of. In fact, I can't say I heard of any of them actually going on into that line of work.

My son is one of top technicians for Tesla in the Southeast. He didn't go to a tech school, he was aways just my little helper. He passed a test for a diesel shop job while in college and worked there for a few years after college. Tesla hired him for his work experience and he out performed most of the techs at Tesla on day one. I'd love to take the credit for his advancement but he earned that himself.

He loves driving his 08 f250 powerstroke to work. Now back on topic

I had a Grand Cherokee with a 3.6l. Not very long though. I felt it was under powered. I still have my 5.7l GC. It is better, but it is under powered for a 5.7l. It gets the job done.

I would like to see Jeep come out and admit to putting out a crappy cam lifter setup in some of the 3.6l engines. It seems that even a few people have had lifter and cam issues a second time with oem parts. I'm at 63k miles now without any perceived issues. I can't hear certain frequencies. I would repair my 3.6l if it was just a cam and lifter. Adding a new cylinderhead to the mix, I would consider a low mileage copart find or a reman

 

[ShadowsPapa]

My son is one of top technicians for Tesla in the Southeast. He didn't go to a tech school, he was aways just my little helper. He passed a test for a diesel shop job while in college and worked there for a few years after college. Tesla hired him for his work experience and he out performed most of the techs at Tesla on day one. I'd love to take the credit for his advancement but he earned that himself.

He loves driving his 08 f250 powerstroke to work. Now back on topic

I had a Grand Cherokee with a 3.6l. Not very long though. I felt it was under powered. I still have my 5.7l GC. It is better, but it is under powered for a 5.7l. It gets the job done.

I would like to see Jeep come out and admit to putting out a crappy cam lifter setup in some of the 3.6l engines. It seems that even a few people have had lifter and cam issues a second time with oem parts. I'm at 63k miles now without any perceived issues. I can't hear certain frequencies. I would repair my 3.6l if it was just a cam and lifter. Adding a new cylinderhead to the mix, I would consider a low mileage copart find or a reman

I always thought my wife's Grand Cherokees, when she had them, outperformed the Gladiator but then I was comparing a lower-sitting, very different vehicle perhaps with different mapping in both the PCM and TCM areas. Those WK2s would get out and scoot. I got a loaner Grand Cherokee from the dealer - and at first thought maybe it was a V8, (trailhawk????? maybe up a level or two, can't recall now), anyway, I let 'er rip at the stop light near the dealership and swore it had more guts than any WK2 we'd ever owned and even my JT. Then I realized - nope, it was still a 3.6
But it performed VERY differently. I was thinking that it would be a good one to own, it was gutsy for some reason.

The parts are case hardened - so once that layer is compromised, the rest goes really fast.
There are other processes they could use - or even other treatments that could be done on top of that.

Non-roller lifters in a V8 rotate as the cam lobe rubs on them. (this also helps keep the cam from walking, or moving forward or fore and aft as it runs - no, it's not the chain that's really responsible for that). The forces and angles of the cam that cause rotation hold the cam back in the block (roller cams require another means of holding the cam from walking). The rotation means you don't have the same exact areas contacting each other over and over and over. The wear is spread, the load keeps moving on the lifter. These don't have that advantage. So it seems to me they need treatment above and beyond a typical V8 flat tappet/non-roller cam.

 

[Stan H]

other treatments that could be done on top of that.

Yes like cryogenic. On knife making for instance the steel is hardened all the way through by different processes
Wonder what the hardness rating of the cams are on these motors ?

 

[Stan H]

I just had a thought
Could it be that the metal composition of certian batches of cams is not correct ?
I know there are multiple multiple grades . 4140, 4310?? ( something like that ) etc.. hmmm
Or does any of that matter beyond the lobe hardening ?

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