Turbo Kit Test TJ
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Brianj5600
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Possibly, hood slopes down there so less room available.
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OP
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Ah, I see. It might be close. The turbo inlet is pretty much inline with the front valve cover breather.
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Air to water on top of the valve cover, and a heat exchanger in front of the radiator.
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The factory airbox is going back in to feed the turbo. It looks like a lot of space right now, until everything gets put back.
I haven't heard this said but if anybody did they have zero clue what they are talking about.
I’ll be interested to see if there is enough space for steering/tranny coolers that always seems to be the problem with turbos.
I am enjoying watching your thread.
Me too, this thread is very interesting. I'm looking forward to the upcoming discussions reg. packaging everything.
Are you going to do the ECM tuning yourself @Jezza ?
@Grover728 are you watching this thread?
I’ve seen videos of guys building strokers and their dyno tests provided peak numbers way above my usable rpm range.
I don’t know about comparing it to the stock 4.0 I just know when I see those peak numbers I don’t care bc I want something more aligned for my uses and I don’t run above 3k very often.
Someone mentioned the cam which makes sense to my little brain, but I forgot more than I ever knew when it comes to that part of the engine.
Forget peak, look at the average area under the curve. For the stroker that @Woodrow posted earlier, you can see the whole curve moved up. That will be a difference you can feel across the whole RPM range... Which is what you're looking for.
I hate to talk about the butt dyno much because it’s totally subjective. However, I do enjoy driving my TJ with the stroker a lot more than the objective but underwhelming peak dyno numbers might lead you to believe.
I understand it’s moving up but wouldn't I want to maximize the power in my usable range? As in, move the peak curve into mid range or even to 3,600 to 4k rather than around 5k?
Disclaimer: I’m a dumb dumb trying to understand this better so I appreciate you going over this.
This makes sense considering the curve appears to be similar to the stock 4.0L but with more power.
The only thing that scares me from being all in on a stroker is the potential for reliability issues. I’ve read that there are ways to mitigate that concern but I need more education on the subject to know what is good info.
You need to compare the two dyno charts (stroker vs stock) and the stroker will make gobs more power at lower rpm compared to a 4.0. Doesn't matter where peak power is. More down low is more down low. Strokers in general shift the entire power band to the left without changing peak power figures all that much unless you do stuff like headwork, bigger cam, etc.
That ties in with another misconception I hear all the time about turbos being bad for low end power. Yes they don't give you off idle power like some kinds of superchargers, but they don't HURT power there either. If you need more power at 1200rpm on the trail, gearing is your issue and a turbo/supercharger won't fix that. Most people need more umph 2200rpm+ i.e. street driving or trying to keep wheel speed up in mud.
That ties in with another misconception I hear all the time about turbos being bad for low end power. Yes they don't give you off idle power like some kinds of superchargers, but they don't HURT power there either. If you need more power at 1200rpm on the trail, gearing is your issue and a turbo/supercharger won't fix that. Most people need more umph 2200rpm+ i.e. street driving or trying to keep wheel speed up in mud.
Ahh I didn’t know that head work could effect where the power is made. Would porting the throttle body and running +1 valves do the same since they also allow more air to flow?
My understanding is that a smaller turbo helps with the lower end by spooling up sooner and at worst just does nothing for u if it has not yet spoiled up. So won’t help in rock crawling for example but it won’t hurt anything either.
IIRC the Banks turbo kit put power down lower in the range than the SCs discussed in a thread, but maybe the SC output could be adjusted lower into the range with a smaller pulley? I’ve never had a turbo or sc so I have no experience.
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Very much so. Small ports, within reason, lead to better velocity and volumetric efficiency down low while sacrificing breathing capabilities when more air flow is necessary, i.e. larger displacement and/or higher RPM. The reverse of that is also true.
Yep. Here’s some of what little I know on the topic:
I think a big point is that putting a slightly hotter cam with stiffer valve springs increases cam wear given the flat tappet (non-roller) lifter set up. This is particularly an issue, because modern oils have much lower zinc content to protect catalytic converters. ZDDP (Zinc Dialkyl DithioPhosphate) is a necessary lubricant especially during break-in for older design engines. Based on some reading, in the past, minimum ZDDP was standardized by the American Petroleum Institute (API) to around 1200 ppm. This was reduced to 800 ppm in 2004. It’s hard to find the exact ZDDP content for a given oil. I use Castrol GTX 10W40 in my TJ (because I always have-no better reason than that). I assume it has around 800 ppm ZDDP, but I may be wrong. If I’m right, my motor should probably have another 500 ppm or so to protect the cam. Lucas TB Zinc plus has 50,000 ppm. So, in 6 quarts (192 oz), 1.92 oz of Lucas TB plus (I rounded up to 2 oz) should add the desired 500 ppm of ZDDP. I realize there are a bunch of assumptions here…
Golen has a good rep and my engine came with a 3 year warranty a bottle of zinc additive for use in the 1st oil change after 500 miles with the break in oil. I’ve got less than 5000 miles on my stroker so I really can’t say anything more about reliability.