Not sure what kind of response that is. lolol


Here's a company that provides EVERYTHING you need... INCLUDING the 5.3 LS engine, with headers, for just over $6K
With this website you can add a different transmission or the bigger 6.0 engine for more money if you like, and they give you a quote of which ever option you choose right on the web site. There's a 15 minute video of them doing the work on a CJ7. They will even rebuild your old transmission so it will work with the package you choose.
Again... I'm talking doing it yourself.

Complete Jeep V8 Swap Packages | Novak Conversions

 

That was a great video, but, is no where near the same as doing a swap into a JK, with all the modern OBDII electronics involved. It is also worth noting that a 1997+ GEN III 5.3L will net you NO MORE THAN 225 WHP and 245 WTQ. LESS than our 3.8L Supercharger kit (240 WHP, 260 WTQ), which installs in 7 hours. Food for thought. Agreed, a V8 sounds Great, but if your buying an engine with 151,000 miles, to come CLOSE to the cost of a supercharger upgrade. Well, to each their own.

RIPP

 

Although you're not completely wrong about the Gen III LS you're not completely right either. There are soo many different type of LS engines offered... Even in 1998 the Trans Am and Camaro's had over 300 hp, but I'm not talking about any specific LS motor, especially since you could get a 2003 6.0 with 300 hp as well, or a 2007 5.3 with 315 hp and even the '07 6.0 with over 350 HP... Also even if you got the bare minimum LS motor... Just changing an entake or a cam can get you 30-50 or more extra HP. The LS engine is VERY compatible with almost all upgrades.

I only talked about the ls with 151,000 miles to just prove a point that there are tones of LS engines out there to buy for cheap. I had a 6.0 with transmission set up that didn't even have 50K miles on it for under $1,200 from a scrap yard. So they are out there for the taking, and it can be done for around the same price as a supercharged 3.8.

There are pros and cons to either upgrade... Pro to an LS swap is that the LS could handle whatever you throw at it... You could even supercharge it.
The 3.8 I doubt would take much more than 300 hp, and I'm not sure how it would even like it or how long it would even last with 300 hp. An LS you can take it to over 500 hp and you are not going to hurt that motor.

Pros about supercharging the 3.8 is... It's a much faster upgrade for sure, and you don't have to change much at all... The LS has tones of mods you will have to do to it to make it work.

I think everyone has missed the point on this post in the 1st place... I even stated... "I'm not talking about supercharging or engine swaps."
I just wanted to know if there were other things you could do... If anyone sold upgraded parts for the 3.8. Could you port and pollish your intake and heads to make more power? Are there other T.B. besides the Viper? Does the Viper T.B. really work? Are there #'s out there to prove it?

I just read a post where someone did just that... he ported his intake and heads, and he stated he didn't have #'s but the extra power he got was felt more than any upgrade he's ever done prior to that.

Like you said, to each their own... I'm not set on anything as of yet... I was just hoping there were much smaller things I could do to make some extra ponies. I definitely want some headers and a viper T.B. to go along with my Hypertech programmer. Also... Are there better programmers out there then the Hypertech? I know there are lots out there, but are there better ones?

 

If you look at the history of the 3.8 engine, it's a stroked 3.3 engine that's pushed to it's naturally aspirated limit. The engine configuration (larger bore by shorter stroke favors Hp over tq) is also limiting and to top it off, a 300 Hp Honda (naturally aspired) makes that peak Hp at 6000 rpm, but a jeep is a heavy brick on wheels that take torque to get it moving and therefore the 40 Hp Honda has at 2000 rpm will stall out on a jeep if you get my meaning.
The issue of comparing it with a Chevy LS or hemi is that the configuration and added two cylinders make it very versatile and responsive to mods for low or high rpm applications. Ls1 is big bore-smaller stroke, ls3 a more square bore x stroke. You can build a cam with more lift or duration profiles, but if the intake design isn't good, it's then wasted. The big cylinder with shorter stroke and a suffocating head/intake design, fireing order, exhaust ports, all contribute to a design that wasn't made for the application. It was a fwd car/minivan motor. They forced some torque out of the design but it's at the wall. An aftermarket looking at what it would take to make it work and giving up on it. You'd have to change the fireing order (new custom crank shaft) so you can get a better intake profile (tuned port), so you can have better heads and a custom cam. One can't be done without the other, so that's why nobody wants to touch that engine. It's almost maxed out naturally aspired. Current configuration with cams and heads won't gain enough to be worth it.
That same motor in a car where Hp is the goal, you could pull off more, at the detriment of torque, but it'd weigh less and have less rolling resistance.
Supercharge or sell and get a Penstar jeep.

 

That's good info, I didn't know that it was originally a 3.3 minivan engine punched out to a 3.8.

Although I do doubt it is pushed to its naturally aspirated limits. I got even more HP by just adding a Hypetech to it, which obviously proves it has more. I’ve also been told on this site several times that adding Ripp headers by it's self makes for a fairly good jump in powers as well, and that adding a CAI with the headers makes for even more power gains. It’s no secret by now that adding a Viper throttle body makes for power gains. So obviously it’s not pushed to its naturally aspirated limits. Close? Probably so,

What kind of gains could you get by adding a Viper T.B., with a CAI, with some Ripp Headers,(or another brand) maybe even a better coil, and a good program? (not even mentioning port and polishing heads and intake)
Are you all saying there’s nothing left? (besides an engine swap, or forced induction)

I would think you could get close to 50 HP by adding all those things together, and the fact you could do all that for under a grand. Yes I know that Ripp headers are over a grand, but I’ve seen header for the Jeep JK go for under $200, on EBay. Maybe I’m wrong.

I will say I am leaning towards the Ripp Supercharger.
Loved this Ripp Video. https://www.youtube.com/watch?v=yclXI_9BTIQ

 

All the mods you said will net you more Hp, but you'll also see a different torque curve which will favor a higher rpm torque peak. I think you're stuck in a Hp = stronger mentality. My background is cars, grew up in the 90's. Had my Firebird with a 400 small block Chevy that I built up and drag raced. Later on I got a 1990 jeep yj with the 4.2l inline 6. While wheeling and doing mods (4.2 is very mod friendly) I found out more Hp = passing on the hiway and torque was for wheeling/stop and go traffic.
When people talk about jeeps, it's about off roading and not how fast you can to get to 100. So, keep in mind that the goal of most is sub 3000 rpm performance (my stall on my firebird torque converter was~ 3200 as an example of an Hp oriented engine). Same with the aftermarket since almost nobody drags jeeps, so trying to get more torque is the goal of the aftermarket, to which the 3.8 (Hp oriented economical designed engine) doesn't have much left. So my ultimate question is do you find off road (first gear) lacking? Of so, because of that engine, multiplying the torque becomes the cost effective approach over increasing engine production (differential/transfer case upgrade). So going to a higher number, 4:1 tran.case, 4.xx:1, 5.xx:1 differentials.
If you find it sluggish for passing. Or getting up to speed, you can also modify the diffs or you can increase hp by increasing airflow.
High flow heads have a trade off in that they don't flow as well in low rpm's. Tuned port intakes are created so that pressure waves from opening/closing valves hit the top (main air chamber) and comes back down with pressure as the valve is about to reopen as the engine runs so that the air molecules starts moving before they would of under normal circumstances, cramming more into the cylinder. This has to do with length, size and shape of the intake runners. They are designed for a specific rpm and they design a cam to match. If you increase head runner size, you increase airflow potential at higher rpms but the lower end of the rpms suffer as the pulses are messed up. Technology has come a long way. The 80's and below were pretty straightforward. Add more air into the engine, you get more power. Honda and the smaller engines had to use "tricks" to accomplish more out of less. (Look at a Honda high reving s2000 hp/torque graph to see their high Hp, then ask if it's usable on the street). Since the 90's, everybody's doing something like that. You can help them by changing restrictions like air boxes, exhaust systems (less restrictions for air vacating cylinders), where the company had to compromise with cheaper mass produced items with less attention to quality.
Torque (where Hp comes from as a function of rpm) is easier to add as you increase the rpm multiplication, increasing torque without increasing rpm is a lot harder and the goal with vehicles such as trucks and jeeps as their use focuses on low rpm duties.
Lots of tricks that manufactueres use to think you'll be getting more Hp. Ask where is the Hp and also what other mods were used to get those numbers. Lightening up the drivetrain's rotating parts can help an engine speed up faster (pistols, crank, rods, valves, flywheel, driveshafts, carriers, axle shafts, brake rotors, rims, tires) and feel faster.

 

x2 on this. Except maybe that Viper throttle body which I'm still really skeptical about actually adding anything.

 

I usually read (versus post) on this thread, but you are seriously skewing the information you just provided to promote your own product.

Dyno numbers are like opinions; often quoted but seldom fully explained or successfully defended. I'm sure you have some "specific" Jeep in mind that produced the paltry 225/245 WHP numbers you just quoted, but what's the whole story? Was this a Jeep running D80 axles, 40" tires and an auto trans using a Mustang Dyno in a high altitude setting such as Colorado? Was this dyno quote even from a JK? Was the engine quoted the 151K example? What #'s did that produce on a compression test? In short, you have a lot of unanswered questions.

Since you specifically quoted the Gen III platform, let me add another nugget of information: A conversion in most every state requires a doner engine from either the same or newer model year vehicle to be street legal. GM was already producing the GEN IV LS platform in 2007. These engines produce 355HP at the crank in the 5.3 flavor. My 6.0L 2013 Silverado 2500 crate engine produces 425HP (340RWHP in current config). That engine was had new for the same price as the 5.3 aluminum block engine of the same year: $3K.

Now I'm not going to pump sunshine and state that a V8 conversion is cheap. Mine was $18.7K installed by MoTech. That price covered the new 6.0, a new 6L80 6-speed with paddle shift, the wiring and R&D (which is why their kit runs $5K), install, + an extended warranty and excellent customer support. A supercharger would indeed be cheaper and @$5K and is viable option for many. However, to claim that it offers the same power and reliability as a LS (or Hemi) V8 is absurd. My 3.8 lasted all of 82K miles in naturally aspirated form before the block cracked. This was driving normally and performing all dealer specified maintenance.

 

With a Jeep driveline sucking out around 30% of the power at the crankshaft, a 300 HP engine will only see about 200-210 HP at the wheels. A swap to a V-8 has some advantages, but adds weight right over the front axle which is extra mass to accelerate and extra mass that has to be accounted for with the suspension and steering components (like adding a winch and bumper) affecting acceleration and handling. I'm sure there is at least a 100 pound difference between the LS and the 3.8 while the 3.6 is about 75 pounds lighter than the 3.8. Why not squeeze a 3.6 with a supercharger and long tube headers into the Jeep instead of the heavier LS? Then you could use the new 5 speed auto or keep the OEM 6-speed manual.
Just trying to think outside the box here...

 

The added weight from what I've read is about 125 lbs... About the size of my wife riding with me. lol Also, you can get an all aluminum block and heads too which would more than likely balance that weight difference out... Or could make it even lighter than the 3.8.

Here is the problems with your question about adding the 3.6 with a supercharger...
1) The 3.6 Pentastar engine is more expensive than the ls motor,
2) No performance parts for the 3.6 really, but performance parts for LS is unlimited.
3) The LS has way more power even in the stock form the the 3.6
4) Now you are spending money to replace the 3.8 with the 3.6, plus spending the money for a supercharger install. That's WAY too much money. You might as well add the LS and the supercharger for less money then the 3.6 with a supercharger.