Is there a reason why you're looking at a turbo vs a supercharger?
Edit: Oops. I quoted an old post.
4.0 performance mods
- Thread starter Eddie Greenlee
- Start date
Is there a reason why you're looking at a turbo vs a supercharger?
Edit: Oops. I quoted an old post.
There are several ways to get a large increase in power from the 4.0, stroker motors, superchargers, and turbos to name a few. I went with the Banks turbo and intercooler setup for several reasons:
Banks reputation - They are known for making quality kits, and have a reputation as one of the best in the aftermarket turbo business. Also, they seem like someone who will be around for years to support their products.
Ease of installation - The Banks kits are complete, I did not need to go to the hardware store for misc nuts, bolts, etc. and did not have to fabricate or customize things to "make them fit". The kit can be installed by one person with hand tools and average skills in 2 ~ 3 days. It does require welding a bung on the oil pan, so you may need to take the oil pan to a welder. The instructions are very complete, follow them step-by-step and it's pretty simple.
It's a small turbo, so it spools up fast. That means no noticeable turbo lag, and Banks claims more torque at 1,600 rpm than the factory motor makes at peak. So it's still a good torque-y motor for rock-crawling. It's *not* a peaky rice-rocket motor.
Turbos are throttle-dependent, not rpm-dependent like a supercharger. If I don't want boost, I just use a light pressure on the throttle. When I put my foot in it, the power is there.
Forgot to add: 100% California Air Resources Board (CARB) legal. No issues passing smog (except for idiot kids that don't know how to verify aftermarket equipment - not Banks' fault).
I've been running the turbo setup for a couple of years now, and couldn't be happier. There are no drivability or reliability issues that I've come across, and I love having the extra power when I need it. Like I said, there are several ways to get big power increases for the 4.0. After weighing the pros and cons of each this is the path I chose, others may choose differently for their own reasons.
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Granted, the ability to tune ignition and fuel flow has improved, but isn't power output of a stock 4.0 still limited by its ability to move air through it?
In my old hot-rod days, to increase power on a normally aspirated engine we would replace the intake and exhaust manifolds with low restriction ones, port and polish the heads, enlarge the valves and replace the cam with one that would open the valves farther for a longer period of time.
Granted, all these things would help the 4.0 also, but that's a lot more hardware and work than just a re-tuned ECM. It would be interesting to see a cost/benefit comparison of a 4.0 with all the above modification vs bolting on a supercharger or turbo.
Brianj5600
TJ Expert
I think my 04 has 8.8 cr. Low compression motors can be over advanced and lose power with out detonation. I also agree with Jerry that too much octane can hurt performance.
Alex0413
TJ Enthusiast
"too much octane can hurt performance" you just told me everything I need to know about your knowledge of engines
Brianj5600
TJ Expert
Alex0413
TJ Enthusiast
The head is certainly the bottleneck on the 4.0. I would love to see a custom head similiar to what a 2JZ runs grafted onto a 4.0, it would be crazy!
cat back exhaust: $250 canned tune: $400 = 25WTQ for $650, pretty cheap
Supercharger or turbo: $2500 - 4K = +150WTQ
boost is obviously the way to go, but not in everyones budgets
Over time, yes it can. The higher the octane, the slower it burns and the harder it is to ignite. That's what octane does. A higher octane than the engine was designed for cause it to leave deposits behind. True.
Alex0413
TJ Enthusiast
sure, but that doesn't pertain to a 93 octane tune. Tuning an engine to 93 octane optimizes the engines timing and fuel to exploit the resistance to combustion of the higher octane and maximize efficiency and power.
Some people just have to be right and feel compelled to have the last word even when they have only superficial knowledge of a subject.
Generalize enough and almost anything can be true.
Ok doc, you're convinced of all this and nothing being said will change it so I'll back out of further discussions here. I'll end my part of this by saying we'll just have to agree to disagree with your conclusions on just how much benefit running 93 octane in a 4.0 engine with stock compression will help.
Translation: I stamp my feet and leave the room in a snit when people won't defer to my superior knowledge and intellect.
Well, I don't know what head 2JZ runs, but there's this:
https://wranglertjforum.com/threads/4-0-edelbrock-performance-cylinder-head.7806/
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Alex0413
TJ Enthusiast
That thing looks like a huge improvement, I've been waiting to see some dyno numbers on these, especially with a big cam and boost.
2JZ has a cross flow head (and is a straight 6 too), having the cross flow head on a 4.0 would be so much easier to work on and allow some nice big long tube headers to be fabricated. I don't have a machine shop or the fabrication skills capable of making that work though LOL
Ha ha, I've always thought of the Nash/AMC/DC/FCA 6 cylinder as more of an agricultural motor - a tractor engine that's perfect for Jeepin'.
Brianj5600
TJ Expert
I was not talking about 93 octane. This is from the VP page.
https://vpracingfuels.com/about-us/faq/
CAN YOU OVER OCTANE AN ENGINE? IF SO, WHAT HAPPENS?
Yes you can over octane an engine. Generally you will get sluggish throttle response. Also you may get fouled plugs and deposits in the exhaust ports and headers. When an engine is trying to burn a fuel that has too much octane, the burn rate is incorrect and all of the fuel won’t be used up. This excess usually gets left as a deposit or gets pushed out the exhaust. It is important to match your engine’s needs with the correct fuel.
Alex0413
TJ Enthusiast
Once again, this doesn't pertain to a 93 Octane tune. Or the fact that a 93 octane tune will make more power than an 87 Octane tune.
But yeah i see how that certainly applies with 110 octane lol
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TheGanzman
TJ Enthusiast
Lord . I need a nap.
Seems like topics that are fundamentally numerical , for instance - like gearing , octane and such really carry a lot of emotional attachment with everyone's viewpoint for some reason.
Anyway , we all have viewpoints based on all we have seen, read heard and experienced ....and we often have blind spots and gaps in what we know to be true .
It is widely considered that the best use of higher octane fuel is for higher compression engines , to slow the burn and prevent predetonation. It also seems that different octane levels are designed to match the engines needs.
Jerry Bransford has no intention but to help and inform others and share the lessons he has learned along the way. His knowledge is both broad and deep, and he would only bow out because he’s not going to try to beat it into someone’s head.
Back on topic, could we lay out performance stages , such as stage 1 - do this this and this and gain x horsepower, stage 2 ,etc etc
I do like the thought that the aftermarket does learn , and also; , the 4.0 gets a bad rap for being untunable because it doesn’t respond well to the first mod everyone tries -airflow.
Also, in terms of sheer performance, I wonder what common engine a super or turbo charged 4.0 feels like . It’s gotta be great.
Seems like topics that are fundamentally numerical , for instance - like gearing , octane and such really carry a lot of emotional attachment with everyone's viewpoint for some reason.
Anyway , we all have viewpoints based on all we have seen, read heard and experienced ....and we often have blind spots and gaps in what we know to be true .
It is widely considered that the best use of higher octane fuel is for higher compression engines , to slow the burn and prevent predetonation. It also seems that different octane levels are designed to match the engines needs.
Jerry Bransford has no intention but to help and inform others and share the lessons he has learned along the way. His knowledge is both broad and deep, and he would only bow out because he’s not going to try to beat it into someone’s head.
Back on topic, could we lay out performance stages , such as stage 1 - do this this and this and gain x horsepower, stage 2 ,etc etc
I do like the thought that the aftermarket does learn , and also; , the 4.0 gets a bad rap for being untunable because it doesn’t respond well to the first mod everyone tries -airflow.
Also, in terms of sheer performance, I wonder what common engine a super or turbo charged 4.0 feels like . It’s gotta be great.
Businesses that say " the customer is always right" typically sell a low priced item , like a hamburger , and they sell millions . - Carl Sewell , Luxury Car Dealer , Texas.
The customer is not always right , especially when they are taking advantage of or disrupt a business .