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Build thread White '99

You might want to check out the gearhead-efi site for more insight into those values.

I believe you are looking at the right fields. I'm more of a GM EFI guy, personally. I know it's all the same tech, but handled differently. Nice thing about GM EFI is it's been hacked and is able to be tuned on the fly.
 
The bouncing around at idle is normal. Pretty much all efi does that. Your fuel trims indicate it is slightly rich outside it's 0 point so that's not too bad. Big thing would be to drive around under cruise and heavy acceleration and just verifying that the o2 does not stick to a low voltage and fuel trims do not climb high above 0 at cruise (over 15 would not indicate it's adding a lot of fuel)
 
You've got several good Dyno shops in the Henderson and LV area that could run a "real time" data logger with a wide range O2 sensor.
 
The bouncing around at idle is normal. Pretty much all efi does that. Your fuel trims indicate it is slightly rich outside it's 0 point so that's not too bad. Big thing would be to drive around under cruise and heavy acceleration and just verifying that the o2 does not stick to a low voltage and fuel trims do not climb high above 0 at cruise (over 15 would not indicate it's adding a lot of fuel)

So the values I should be looking at is STFT? and LTFT? and O2S B1S1/2?

What does the STFT and LTFT stand for? Im assuming XX fuel trim. and O2s is O2 sensor bank 1 sensor 1?
 
Short term fuel trim and long term fuel trim.
 
https://youtu.be/RL2Dj0jdI2E

Here's a video of the live data stream. I took two pulls from 0-60 under heavy acceleration. Its not WOT because I'm still in the break in phase of the motor, so I didn't want to push it too hard.

Short term fuel trims seem to be pretty steady at 0.0 ad long term sits at 2.3 until I let off the gas and coast. O2 voltage seems to sit at .880 for awhile then drops off.

Not sure How to interpret this info, so I figured I would post a video just for ease.

Not sure how to embed it in the form so It's not click free. oh well.
 
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Sweet. That's the main thing I wanted to know.

I've heard other people say they do the same thing with a new motor, I guess I've been scared to really hit on it haha
 
Not going lean so I'd say it looks ok. FWIW, I run the crap out of new motors. I like some heat/heavy load to get everything seated.

Concur.

After a 20 minute initial idle pull to seat the cam in, I'll do some moderately heavy acceleration and then let the engine brake the vehicle. This seats the rings in.

After that, Run it like you're going to. Don't be gentle, but don't be stupid either.
 
Concur.

After a 20 minute initial idle pull to seat the cam in, I'll do some moderately heavy acceleration and then let the engine brake the vehicle. This seats the rings in.

After that, Run it like you're going to. Don't be gentle, but don't be stupid either.

Good info.

what I've read online seems to jump on either side of that. So I stayed somewhere in the middle. Ive got about 1200 miles on this new motor, so I'm sure my rings and cam have broken in. I'm just nervous to hit on it. Probably unnecessary.




So now that Ive got the running hot due to being lean figured out, now I'm just on to upgrading the cooling system. Vegas temps have moved up above the 100 mark, and the jeep is toying the line with 220-225 coolant temps. Larger radiator and new E fan are coming. And if they don't fix my problem, then I'll be looking into some Efan upgrades. Maybe adding some hood vents, and tilting the back of the hood up would be a good addition as well.
 
Good info.
temps have moved up above the 100 mark, and the jeep is toying the line with 220-225 coolant temps. Larger radiator and new E fan are coming. And if they don't fix my problem, then I'll be looking into some Efan upgrades. Maybe adding some hood vents, and tilting the back of the hood up would be a good addition as well.

I assume you've changed the oil by now? I change the oil at 100 miles, 500 miles, 1500, then go to the regular interval you plan to use. This gets any trash that may be in the block from machining (no matter how careful, you'd be surprised!) out of there quick. If you run a bypass filter (not a filter with a bypass, totally different convo) I'd just change it at 100 and then go to your interval.

Regarding temps- IIWY (and I'll be addressing this soon in my Jeeps- Charleston isn't exactly cool) I'd be looking at an aluminum/aluminum or copper/brass radiator. There's a good thread on that subject, check my recent history. You'd be surprised how inexpensively you can get one of these - like less than $200 - and not at all much more than a quality AL/plastic job.

I also recommend RMI25 as a coolant additive. It's by no means magic in a bottle, but it is darn close! Perhaps a surfactant as well, to improve the wetting effect (and thus heat transfer) of the coolant. Also, what mixture of coolant are you using- in terms of coolant:water ratio? It may surprise you to find that water is the best coolant- but of course it will also rust out your system due to the obvious concerns with iron. Coolant helps negate that (as does the RMI25), as well as addresses concerns of freezing the coolant in the block during cold periods. I'd look into what your lowest temperature you expect to deal with is, and mix the coolant accordingly. IE: if you never get below 15F, there's not a lot to be said for mixing coolant to protect down to -20F.

Of course, this all presupposes you're using the closed cooling system (can't recall your year), everything is in good shape, etc. I really do believe the cooling system in our vehicles was sub-par from the outset, at the best.

Also, before I forget- there was also a Mopar "desert service" radiator for out vehicles, it can be had from Rockauto and others- about $230. It was designed for desert service, and hey I think you live in one..... :) (it's in that same thread)
 
BTW- I have a little experience fighting cooling issues. Stuff a V8 in an S10, you learn these things.

It may surprise you to find that I tried running without a hood entirely, just to get to work... and this actually resulted in my temps going higher. by something like 20 degrees It's partly aerodynamics (oddly enough, in a SAS'd brick with about 10" lift) and partly air management. IE: the brick makes a hole in the air, and you end up with stagnant air in the front behind the pressure wave. Additionally, when I put the hood back on and added baffles around the radiator (god, aren't pool noodles handy?) to force air through it, my temps dropped back about 30 degrees- but still too high. I then added seals (foam weatherstripping) to the fan shroud to make sure I concentrated all the air through the fan hole in the shroud.. and my temps dropped another 15. Still, too hot. All of this was accomplished on the same day so I'd say the info works. Then I did more research and moved the fan back about an inch from the radiator- and temps dropped another 20... which was right where I wanted. Not that I am saying move your fan away from the radiator (Jeep put it where it needs to be unless you're using a non-stock motor), just you'd be surprised what all goes into air management.

TLDR: air management is key. Don't expect much from tilting the hood forward or venting the hood. They may help, yes- I did the tilt to my 90 and don't recall to be honest. But make sure all the baffles and such are present on the radiator surround to make all the available air HAVE to go through the radiator core. Check the condensor and radiator fins for clogging (bugs and dirt, maybe mud!) or damage (there is a comb available to straighten minor damage). Just like your home refridgerator can benefit- greatly- from having the heat exchanged showed a little love, so can your engine. Apparently there's also a known issue with the exhaust gasket at the collector leaking and acting as a blowtorch on the sump. This is going to be resolved by paying attention to the details and fundamentals of physics.
 
A lot of good info here.

Mine's a 99, with the stock radiator and cooling system (closed system?). It seem to me that it is a 2 row radiator as well. As far as coolant goes, I put in one gal Prestone 50/50 mix then gal of water and then about 1/2-3/4 gal full strength Prestone. I don't have a coolant hydrometer, but I figured, as you mentioned, I'd rather have more water than coolant.
fan shrouds are good, and the baffles in the radiator and condensor are clean, The radiator actually looks pretty good. I've never changed it and I've had this jeep going on 6 years, but maybe the previous owner did :dunno:
One thing that I need to change is the efan. Its the older 6 blade style that Im assuming the previous owner put in as a quick replacement. Its worked fine for me up until I put the stroker in. From what I've read the stock 10 blade e fan puts out a good amount of air for its size, (2200ish cfm I think) so maybe that will help with my temps.

Honestly the temps slowly creep up. sits at 190ish for a good while then 210 then it slowly creeps to 220ish. And it does this consistently whether I'm driving on the freeway at 70 or around town. Which worries me that more air isn't going to be enough.

Earlier in my thread I mentioned how much i hated the exhaust manifold that I got, and my feelings haven't changed. the fitment of the manifold was crappy at best and it pushes the exhaust close to the oil pan. I took off some hangers and pried the exhaust away from the pan, so now there's 3ish inches between the pan and the exhaust down pipe. But im wondering if that is enough. And this manifold has the #6 exhaust tube hairs width from the #6 intake runner On the manifold. So I'm wondering if the slow creep in temps is because of the heat transfer from the exhaust to the intake and the oil pan. It seems to make sense. :dunno: Crappy thing is right now, I just don't have the money to put into another manifold, or into cooling fans.


Im on my 4th Oil change. (oil starts to get damn expensive) My next one is due In about 2k miles. I put in thicker 10w40 conventional oil because of the temps here in vegas. Oil pressure stays at 35ish at idle and around 50 at cruise, with 10w30 it would drop into the 20s or so at idle.

I'll take a look into that coolant additive you mentioned and see if I see a noticeable drop in temps. :thumbup:
 
For a coolant additive to reduce Temps, try Water Wetter. Lucas also makes one. Rmi25 is a cleaner. Good idea even so.

Here's what you need to do to address your issue. Remove the exhaust manifold. Wrap it with exhaust wrap. I know it seems rice-ish, but it works. It made a huge difference on my motorcycle, the pipe used to roast my thigh in the summer, it no longer did after I wrapped it. I replaced my exhaust manifold in the wife's ZJ (pretty much identical) and it did a double wrap. It reduced underhood Temps quite a bit. If I was concerned with proximity to components causing heat soak, that's what I would do (in fact I was, and did).

Should cost you less than 50 bucks. I recommend getting the wrap off ebay or Amazon, much cheaper than the LAPS. Don't bother with the special stainless steel ties, I used safety wire (mechanic wire), stainless if you can find it. Use a pair of pliers and basically do a safety wire arrangement on it, running along the length of the runners.
 
For a coolant additive to reduce Temps, try Water Wetter. Lucas also makes one. Rmi25 is a cleaner. Good idea even so.

Here's what you need to do to address your issue. Remove the exhaust manifold. Wrap it with exhaust wrap. I know it seems rice-ish, but it works. It made a huge difference on my motorcycle, the pipe used to roast my thigh in the summer, it no longer did after I wrapped it. I replaced my exhaust manifold in the wife's ZJ (pretty much identical) and it did a double wrap. It reduced underhood Temps quite a bit. If I was concerned with proximity to components causing heat soak, that's what I would do (in fact I was, and did).

Should cost you less than 50 bucks. I recommend getting the wrap off ebay or Amazon, much cheaper than the LAPS. Don't bother with the special stainless steel ties, I used safety wire (mechanic wire), stainless if you can find it. Use a pair of pliers and basically do a safety wire arrangement on it, running along the length of the runners.


Cool, Ill give it a try.

(funny you say safety wire, I am an aircraft mechanic for Delta, and I use safety wire every night) haha
 
Cool, Ill give it a try.

(funny you say safety wire, I am an aircraft mechanic for Delta, and I use safety wire every night) haha

Awesome, I don't need to explain how to do it, why, or why it's superior. ;)

I'm a HUGE fan of the stuff. I had an issue with the 4.3 in my S10 letting go because the "professional" mechanic that helped me replace the engine n '02 told me we didn't need to secure the pump pickup in the pump body (why yes, he is a moron, why do you ask? ;) ). Needless to say after a few years it let go and the pickup was in the bottom of the pan, doing nothing.

I still don't weld the pickup on- but I do safety wire it on. Loop a strand each way, then loop the strands together at the back and done. Problem solved, problem stayin' solved.
 
Just an update.

Went ahead and wrapped the exhaust manifold. Saw a drop in coolant temp, went from 220+ to around 213-215. Still high, but in the right direction.





I bought two wraps from eBay. Soaked them in water for the night to try and keep down the fiber mess. Didn't really work, still a pain. I used a combination of stainless zip ties, and .020 safety wire. It takes some patience and planning to wrap the manifold. turned out good enough.

In an Odd some note, and can't explain why, the engine runs smoother than before the wrap. Maybe its just the jeep it slightly quieter, or maybe the tiny additional scavenging effect that the internet claims. Don't know :dunno:


So, Temps are still too high, so I reluctantly pulled the trigger on a Mopar HD radiator. P/N 52080104AC. Apparently its the factory tow package/ dessert radiator only put in certain XJs. Anyway, its a factory OEM radiator. 299$ was the best price I could get.....:tears: The rad is a two core 1 1/2" radiator. The previous rad was also a factory rad p/n 52079682AE but is a single core, 1 1/4? (as far as my research has shown) Also impressed with my old rad, I mean i have no way to know, but it seems like it might be the original rad, 174K miles, 18yrs, might be day dreaming but I've had the jeep 6 years and never done anything with it other than flushes. So other than my recent issues, no problems.







Anyway, New rad just drops right in, filled it with new fluid, and what do you know, temps now hover between 200 and 210. Right where it should be. :D Took it out and around up some hills and it never went above 210. The temps outside are still in the mid 90s out here in Vegas, so if it can maintain temps now, I feel like when its 117 it should be able to keep its cool. but I guess the real test won't be till next year.

The new rad sits close to the fan clutch, I have about and inch of clearance. I Think I'll be alright since I have the brown dog motor mounts.




All I need now is a new fan Shroud......
 
Inch of clearance ought to be plenty. There shouldn't be that much fore/aft movement even with OEM mounts.

I tried to run 1/4" clearance on my S10 when I stuffed in the V8. bloody stupid! I ended up eating that radiator, which was brand new.
 
Yeah, I'm hoping that doesn't happen here. (also, I'm terrible at eyeballing measurements, the clearance is actually just over 1/2", Feel like it should still be ok) I'm I've got a new fan shroud coming and I'll need to tear into this again to install. But after that I think my engine is officially "Done". Only thing i need to fix on the jeep now is I need to fab up some sway bar links.

I have had some death wobble that I've been trying to fix for the last little bit. I found the track bar heims had some play in them when turning the wheel back and forth. So I replaced both heims, and well as the TREs on the draglink. That took car of my death wobble for a little bit, But ive had it creeping back every so often. Went under and again it seems like its the heim on the track bar. I'm going to have to decide what to do with this
 
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