Jeep Wrangler Forum banner

Banks Turbo for TJ questions: input needed

7K views 23 replies 11 participants last post by  Mikee024 
#1 ·
Hey Jeepers,

I have a 2004 TJ Rubicon (114,000 miles) with 3.25" Rough Country lift (replaced the RC shocks with Rancho 9000s), and running 33s. I'm considering installing the Banks bolt-on turbo kit. The Jeep seems to be running great and not getting any check engine codes. Jeep is a DD and limited off-road use. My question(s):

1) Is a compression test required (or advised) - and why/why not - prior to installing the Banks Turbo kit if I'm not getting any check engine lights/codes?

2) Is a leakdown test required (or advised) - and why/why not - prior to installing the Banks Turbo kit if I'm not getting any check engine lights/codes?

3) None, one, or both tests required, and in which order if I need to do both tests?

Just curious if the metrics for bad compression or leakdown would first be indicated in a diagnostic code.

Thanks in advance for any input and guidance.
 
#3 ·
WHAAT? I thought I still saw the turbo referenced and posted online, but I believe you. I guess if they were discontinued it was for a good reason. Is there an comparable Banks Turbo/PN (or alternative turbo kit thats bolt-on or close) that you'd recommend? Thanks.
 
#4 ·
Lack of demand most likely...
Afaik no they were the only ones of their kind.
 
#21 · (Edited)
Ya nobody was buying them. Boosted Technologies sells a supercharger kit for the 4L.

StackPath

You'll average a solid 8 mpg with the kit so it's not very practical for a daily driver. You could build a stroker in your garage for less $, better fuel economy and way more HP.
This is an old thread, but the reasoning for why the Banks kit went away could use an update.

The biggest issue was that the newest CA emissions test had issues with the 99-04 kits. At least one sub-test thought elevation was at 10,000 ft (MAP sensor related) so the test would not run.

The 05-06 Banks kits didn't have a problem, but Banks decided to pull the product rather than only offer it for the 05-06. I'd imagine sales numbers played a part in this decision. Maybe Banks didn't know there were plenty of 05-06 owners who would have pulled the trigger had they known the kit would be pulled, and that there are people who would buy this kit right now if it was available. Banks isn't known for looking backward after they pull a product, so it's likely never going to happen for the turbo.
 
#6 ·
Strikers don’t last long as rod too short for crank throw making too much lateral force

There was a reason ford made a longer block in 351 then in the 302 as simply increasing stroke = short engine life

Not bad in a frequently replaced race engine but bad idea if you want to keep it and enjoy the longevity inherent of the 4.0


Sent from my iPhone using Tapatalk
 
#9 ·
Does the 4.2L/258 have this problem? It seems like most people feel they are a durable engine if properly maintained. If the carb runs overly rich they can wash the oil off the cylinders and contaminate the oil causing wear, but I don't see people thinking they are short lived. Most people building strokers use a 258 crank and 4.0 rods. The 4.0 uses 6.123" rods vs the 258's 5.875" rods.

I think somebody made a post on this 10 years ago and it has been referred to as fact since. With proper parts and machine work a stroker 4.0 should have no problems.

It's kind of funny that forced induction can benefit from shorter rods. Long rods move the piston away from TDC slower increasing potential for detonation. BMW used a 1.48 rod ratio in a turbo M3, likely for that reason. For comparison a stroker 4.0 has a 1.57 rod ratio.
 
#7 ·
There are solutions to longer stroke applications, most popular is to go with a longer connecting rod and custom pistons that effectively give you a better Rod Angle and remove some stress from the running engine.
When people first started stroking the GM 350 V8 into a 383 with the 1/4 longer stroke they had short life and even block fractures using the stock 5.565 connecting rod from the 400 small block engine. By moving the piston pin up higher in the piston and using a 5.7" connecting rod this same 383 engine became reliable. Good news is so many 383 engines were built that this 5.7" rod piston combo came at a very reasonable price.
With a Jeep 4.0L I think you would be stuck buying custom pistons which would probably be $700 for a set of 6, custom rods again at a high price.
Now with your Turbo addition you would need some type of controller that can add fuel while you add turbo boost. If this is done properly you can add 50% more horsepower and torque safely. If your fuel mix and timing is not perfect in a boosted engine, turbo or supercharger you will melt the piston heads or break the piston rings.
Same is true when adding nitros.
My son is working with a company that does custom turbo applications but they are chasing high dollar cars because those people have the money to burn on a toy.
They have a Porsche Turbo upgrade kit that takes the Porsche 3.8L turbo from stock HP rating of around 500 HP and they are doubling that power to 1000 HP. They have not broken a piston yet because they understand the fuel mix and timing curve and they have created software that does this automatically while you drive. A kit starts at $25,000 to do this. ( and you need $150K to get the car to play with )
No doubt Turbo's offer great power, it has to be controlled. Stock timing might max out at 25 degrees in your jeep, add the turbo boost and that timing must be pulled back to maybe 18 degrees advance or things start burning up fast.
As little as 15 seconds at full boost can melt pistons if the fuel and timing are not perfect.

If power is your goal maybe look into a 4.8L GM truck engine swap. The LS 4.8L has technology that is 20 years ahead of the 4.0L Jeep engine in development.
The 4.0L is a good Jeep engine for low RPM work but the head design is very old 60's technology and limits building it up for power. The old head design uses exhaust and intake on the same side of the block, this is a huge limitation for good power. All modern engines are now Cross Flow, Intake one side, Exhaust the other which helps move the flow of air and exhaust in and out while managing heat. Much better design.
Simple comparison, look at the GM 4.0L trailblazer straight 6 cyl with a modern head design, 295 HP in a tame tune. Jeep 4.0L has 200 HP and is pretty much maxed out. The GM design will offer better gas milage, much higher RPM capability and similar torque rating.
It actually makes the same horsepower as the GM 4.8L LS V8.
BMW, Toyota, Nissan, Mazda, Ford and more all offered modern engines that offer the newer technology. The Jeep is a good truck motor but design of this engine limits what would be smart to do for upgrades.

My 2 cents would be leave the 4.0L Jeep engine and enjoy it for what it offers stock.
This old design engine is not a good choice for a Turbo if you want reliability.
If you want more power go for another power source. That is how I see it and I will take my lumps for voicing this.
 
#17 ·
Got any actual examples of them lasting

If not just gonna say when you get some let us know

Otherwise won’t waste time on your unsupported conjecture

Lists of documented high mileage stock 4.0 so far not seen any long lived strokers


Sent from my iPhone using Tapatalk
 
#18 ·
Answers are no, it is not an issue and nothing.

I'm surprised you let me cherry pick. I think the second post tells the story about why there are few high mileage strokers. I live less than 4 miles from work and only rack up around 5000 miles a year. I'll let you know in 20 years if mine makes it to 100,000 miles. Just because I don't know of any 100k strokers doesn't mean there are not any or that no 4.6 or 4.7 could last 100k or even 200k.

From Jeepstrokers.com

Definitely not. Many stroker engines had cam failures early in their lives either due to improper cam break in, using low ZDDP oil, valve springs that were too stiff, incompatible parts, or build errors.
With good quality parts that are compatible with one another combined with good machine shop work, careful assembly, and proper break-in, a stroker should last well over 100k miles. Mine's closing in on 80k miles.

Same poster as above adding why there are few high mileage strokers.

Actually I don't think there are many strokers that have even passed 100k miles yet, let alone 200. Many of the Jeeps that are home to strokers aren't daily drivers so they don't rack up high mileages very quickly.
I've done 67k miles on mine since I first fired it up in July 2004. When the Jeep was my only vehicle I drove it a lot and racked up 37k miles on the stroker in the first 2-1/2 years. Since I bought my Mustang 5 years ago I've only added 30k miles on the stroker and if I continue at that rate, it'll take me at least another 5 years to reach 100k.

My stroker's done 49k miles and it runs like a champ. Only problem was Crane 753905 cam/lifter failure at 34k miles. Replaced them with stock cam/new lifters and been OK ever since (knock on wood).

i have over 20,000 miles on my $300 4.5 stroker and no problems(all done in my garage and no machine work). other that the few parts related, one injector worked when it wanted and the coil, cap, rotor, plugs, wires, had to be changed but that happens to stock 4.0. and thats after taking it to silver lake(sand dunes) and putting it the mud, countless times.

Mine had 18,000 miles on it when my Jeep got totalled. I had a few bugs to work out, due to roller rockers, and larger diameter valve springs hitting my valve cover baffle. After that was resolved, I had no problems. I used a custom ground Engle cam, Mopar performance springs, and crower roller rockers. I used a solid pin to retain the cam.

This applies to all Jeep forums

The majority of folks on JF really have no idea what they are talking about...........The few that actually bring something to table are overshadowed by those who talk Parrot...........
 
Top