Engine upgrades?

[Jbergun]

Saw those funny thing is one was done and traded off really quick ( since it was a big old pile of doo doo, other one there was a vid made and then it disappeared. One guy on here did one, made a vid of it backing out of the garage with a few things needing finished and then he disappeared. haven't really seen one long term ( over a few days) yet

Yeah seen that thread he was Honduras he spent a while on the site updating then backed out of that garage and we lost him

 

[CactusJacked]

Yeah seen that thread he was Honduras he spent a while on the site updating then backed out of that garage and we lost him

He prolly got locked up for speeding along at 120 mph. Would be easy to do when you're used to it not going much faster than interstate speeds. :happy175:

 

[Jbergun]

He prolly got locked up for speeding along at 120 mph. Would be easy to do when you're used to it not going much faster than interstate speeds. :happy175:

Prison in Honduras probably isn't half as pleasant as prison here in the states:happy175::happy175::happy175:

 

[tjkj2002]

I say do the 4.7 swap and prove all the nay-sayers wrong. It has been done successfully before, so you can too as long as this kind of task is within your skill set.

2 where done and since they both disappeared there is no way to say anything about successfully.






To the OP..................


If you don't have $35k laying around to buy a Mustang there is no way you will get any more power(reliably) from the 3.7 for much less.To properly turbo it(or supercharge it) you'd be looking around $15k at least,more if you have the 42RLE trans or manual trans.Expect to dish out another $5k+ if you have the 42RLE which wouldn't last at 300hp and you'd be dropping $1k every few months on a new clutch(and flywheel) with a manual and a new trans not long after that.The manual trans can barely handle a stock 3.7 and yes they put the same manuals behind 4.7's in Dakota's but they are also de-tuned to make less torque.




By the way my KJ weighs over 6200lbs(4000lbs was stock weight) and turning 35" tires(SFA'd) and still using a 100% bone stock 3.7 and 45RFE.Gear ratio is what helps the most,I'm running 5.13 gears,stock was 3.73.

 

[dude1116]

2 where done and since they both disappeared there is no way to say anything about successfully.






To the OP..................


If you don't have $35k laying around to buy a Mustang there is no way you will get any more power(reliably) from the 3.7 for much less.To properly turbo it(or supercharge it) you'd be looking around $15k at least,more if you have the 42RLE trans or manual trans.Expect to dish out another $5k+ if you have the 42RLE which wouldn't last at 300hp and you'd be dropping $1k every few months on a new clutch(and flywheel) with a manual and a new trans not long after that.The manual trans can barely handle a stock 3.7 and yes they put the same manuals behind 4.7's in Dakota's but they are also de-tuned to make less torque.




By the way my KJ weighs over 6200lbs(4000lbs was stock weight) and turning 35" tires(SFA'd) and still using a 100% bone stock 3.7 and 45RFE.Gear ratio is what helps the most,I'm running 5.13 gears,stock was 3.73.

Do you have a new engine in yours yet? (Thread jacked!)

 

[Hockeygoon]

2 where done and since they both disappeared there is no way to say anything about successfully.






To the OP..................


If you don't have $35k laying around to buy a Mustang there is no way you will get any more power(reliably) from the 3.7 for much less.To properly turbo it(or supercharge it) you'd be looking around $15k at least,more if you have the 42RLE trans or manual trans.Expect to dish out another $5k+ if you have the 42RLE which wouldn't last at 300hp and you'd be dropping $1k every few months on a new clutch(and flywheel) with a manual and a new trans not long after that.The manual trans can barely handle a stock 3.7 and yes they put the same manuals behind 4.7's in Dakota's but they are also de-tuned to make less torque.




By the way my KJ weighs over 6200lbs(4000lbs was stock weight) and turning 35" tires(SFA'd) and still using a 100% bone stock 3.7 and 45RFE.Gear ratio is what helps the most,I'm running 5.13 gears,stock was 3.73.

Not to mention the work the transfer case, drive shafts and axles will need. More than a few fail on a regular basis with just the stock HP of the 3.7 being fed to them - imagine what 300HP will do to them - especially if you use it.

 

[KYLiberty]

@OP

I'd highly recommend just regearing to 4.10's, getting an aggressive tune from B&G, and be done with it. You will have a noticeable performance gain. To get any gains beyond that, you will have to spend huge amounts of money and you will break things and then spend more money to replace them. If you go back a decade, you will see that I know a little bit about what I'm talking about.

 

[CactusJacked]

2 where done and since they both disappeared there is no way to say anything about successfully.

So what you're saying is once you leave the small confines of this website, the KJ world drops off into an empty cavern of nothingness? :shrug:
Look around on the internet, it's been done successfully more than once.
About the other drive train components not holding up, you want to drive smart. I kept the stock 4 cylinder rated Datsun rearend with my 350 swap, but I didn't beat the crap out of it. I would get it rolling in 1st, then jump on it. It lasted for years up to the day I sold the truck. Now, start doing hole shots off the line and yeah, you may start breaking some things you don't want to.

 

[tjkj2002]

So what you're saying is once you leave the small confines of this website, the KJ world drops off into an empty cavern of nothingness? :shrug:
Look around on the internet, it's been done successfully more than once.
About the other drive train components not holding up, you want to drive smart. I kept the stock 4 cylinder rated Datsun rearend with my 350 swap, but I didn't beat the crap out of it. I would get it rolling in 1st, then jump on it. It lasted for years up to the day I sold the truck. Now, start doing hole shots off the line and yeah, you may start breaking some things you don't want to.

I'm on many sites that the same 2 people bragged on but once they had pics of the engine in place they totally 100% disappeared with no response for over a year.They bragged so much about doing it that they must have been ashamed when it was a total failure,until either post otherwise there was no success stories yet.


I do know of 1 successful V8 swap into a KJ but you will never hear of it since the owner is rather private and uses it for dune running.I know the builder the KJ was SFA'd and has a 6.1 HEMI in it.

 

[CactusJacked]

And how many people told you were nuts for wanting to do what you did to yours? Probably more than one. The more I hear someone say "it can't be done", the more I find a way.
There are a couple converted Libertys on youtube, you might find more with a google search. I'm sure there may be others done by people who may not be computer savvy, or like the one you personally know. Few and far between yes, but still been done.

 

[dude1116]

I'm on many sites that the same 2 people bragged on but once they had pics of the engine in place they totally 100% disappeared with no response for over a year.They bragged so much about doing it that they must have been ashamed when it was a total failure,until either post otherwise there was no success stories yet.


I do know of 1 successful V8 swap into a KJ but you will never hear of it since the owner is rather private and uses it for dune running.I know the builder the KJ was SFA'd and has a 6.1 HEMI in it.

Oh man would I love to see that. I'm drooling just thinking about it.

 

[Senistr]

As many simulated racing games, the very FIRST thing I do to anything to make it go faster, are not engine, but transmission upgrades. With what's in the jeep, from what I have read, you would need to pretty much change everything. Changing out the transmission, drive shaft (like going carbon fiber), changing the clutch, flywheel, and even changing out the diff can shave pounds off of the jeep and give you more power to the wheels, without actually increasing it's power.

Another thing you can do is take out added weight which will give it more power. Instead of using the factory seats, switch them out for lighter racing seats. If you're mechanically inclined, then take off the stock hood, and make a carbon fiber hood to shave weight. I am sure you can do the same to the doors as well, or leave them off and build a door that resembles the removable doors like on wranglers that have the cargo netting. Using steel wheels? Try to find an aluminum counterpart and switch those out, shaving even more weight to the Liberty.

Everyone has a preference, but as I read from everywhere because as a computer technician, I am knowledge hungry. From what I read, and understand, several things do not work because of the engine was designed to give you the mac straight from the factory. Cold air intakes don't work because it doesn't get enough air to make it worthy. BUT if the CAI is lighter than what's in, it might be worth it to you. Making a new hood? Design it to work with the CAI to give you the power you want.

Everything is built on a dream. If you want to dream big and "try" to prove people wrong, then do so. Document it, take pictures, and support the data. Just because something hasn't been done properly, doesn't mean someone else can't. Read what didn't work and use common sense to apply if it can actually be done. You don't take a surf board to a mountain and try to use it as a luge.

 

[Sasquatch]

As many simulated racing games, the very FIRST thing I do to anything to make it go faster, are not engine, but transmission upgrades. With what's in the jeep, from what I have read, you would need to pretty much change everything. Changing out the transmission, drive shaft (like going carbon fiber), changing the clutch, flywheel, and even changing out the diff can shave pounds off of the jeep and give you more power to the wheels, without actually increasing it's power.

Another thing you can do is take out added weight which will give it more power. Instead of using the factory seats, switch them out for lighter racing seats. If you're mechanically inclined, then take off the stock hood, and make a carbon fiber hood to shave weight. I am sure you can do the same to the doors as well, or leave them off and build a door that resembles the removable doors like on wranglers that have the cargo netting. Using steel wheels? Try to find an aluminum counterpart and switch those out, shaving even more weight to the Liberty.

Everyone has a preference, but as I read from everywhere because as a computer technician, I am knowledge hungry. From what I read, and understand, several things do not work because of the engine was designed to give you the mac straight from the factory. Cold air intakes don't work because it doesn't get enough air to make it worthy. BUT if the CAI is lighter than what's in, it might be worth it to you. Making a new hood? Design it to work with the CAI to give you the power you want.

Everything is built on a dream. If you want to dream big and "try" to prove people wrong, then do so. Document it, take pictures, and support the data. Just because something hasn't been done properly, doesn't mean someone else can't. Read what didn't work and use common sense to apply if it can actually be done. You don't take a surf board to a mountain and try to use it as a luge.

All sound advice. The catch being that I'm not trying to build a race car. So throwing out everything and sitting on bicycle seats just won't cut it. Besides, I personally account for most of the excess weight on the rig.

Switching to a manual transmission is at the top of the priority list. Nothing saps power more than a slushbox.

I'm not setting out to prove anybody wrong about anything. Rebuilding an engine with beefier aftermarket parts is hardly a revolutionary idea. I only asked whether the parts were available. Turns out the parts are available. But it's unknown whether anybody has used them yet. If somebody rebuilds an engine with the aftermarket pistons and STILL blows it up with boost then I guess we'll know the problem goes deeper. If I can talk my wife into letting me build a spare engine I'll gladly buy the parts and start working on it. Our current situation makes that unlikely.

As for the endless debate over whether or not V-8s have been successfully swapped, they have;
https://www.youtube.com/watch?v=yYIw_9rxIe4&spfreload=10
https://www.youtube.com/watch?v=V_PwhhH20rk&spfreload=10
My favorite Even though it isn't running yet.

So a swap is an option. But it seems like a lot of work for very little gain. The 4.7 just isn't that much more powerful than the 3.7. I'm betting a blown 3.7 would be cheaper and more powerful than a 4.7 swap. Of course, a blown 4.7 swap would be wonderfully insane.

 

[KYLiberty]

All sound advice. The catch being that I'm not trying to build a race car. So throwing out everything and sitting on bicycle seats just won't cut it. Besides, I personally account for most of the excess weight on the rig.

Switching to a manual transmission is at the top of the priority list. Nothing saps power more than a slushbox.

I'm not setting out to prove anybody wrong about anything. Rebuilding an engine with beefier aftermarket parts is hardly a revolutionary idea. I only asked whether the parts were available. Turns out the parts are available. But it's unknown whether anybody has used them yet. If somebody rebuilds an engine with the aftermarket pistons and STILL blows it up with boost then I guess we'll know the problem goes deeper. If I can talk my wife into letting me build a spare engine I'll gladly buy the parts and start working on it. Our current situation makes that unlikely.

As for the endless debate over whether or not V-8s have been successfully swapped, they have;
https://www.youtube.com/watch?v=yYIw_9rxIe4&spfreload=10
https://www.youtube.com/watch?v=V_PwhhH20rk&spfreload=10
My favorite Even though it isn't running yet.

So a swap is an option. But it seems like a lot of work for very little gain. The 4.7 just isn't that much more powerful than the 3.7. I'm betting a blown 3.7 would be cheaper and more powerful than a 4.7 swap. Of course, a blown 4.7 swap would be wonderfully insane.

:freak3:

OK. Don't listen to any of us that have experience in this. Look to video games and dreams.

The truth is that you can definitely build a blown 3.7, but to do it you are going to spend $10K-$15K by the time you properly build the engine for it. If you don't have a very early KJ with the 45RFE, you will destroy the mini van 42RLE in a very short time. Look at the JK owners that have supercharged and destroyed the 42RLE very quickly. Also, if you don't get the programming right, you can't put more than 220 HP to the ground. The computer simply won't let you no matter what you do. Just look at the Kenne Bell supercharged KJ that was only capable of a 16.1 quarter. They never figured out the programming. My KJ has one of the only computers that will allow it and it is a custom tune. It's actually the only KJ computer that I know for a fact that will allow it. It's what allowed me to blow one engine with an air/fuel/nitrous mistake. Without figuring out the power problem with the computer, it would have simply richened up the mix and ******** the timing.

 

[Sasquatch]

:freak3:

OK. Don't listen to any of us that have experience in this. Look to video games and dreams.

Exactly what am I not listening to? What experience? Nobody here has rebuilt an engine with those aftermarket pistons. So nobody here knows if they are better than the stockers. Video games and dreams? I haven't played video games in decades. And NOTHING I have posted here is the stuff of dreams. Rebuilding an engine with beefier parts is basic stuff. Is "video games and dreams" really your go-to insult for a 45-year old man? I did my first brake job when I was five. How many people here have been turning wrenches for four decades? I bet there's only a handful of people here with as much experience as me. Or are you trying to say the KJ is so unique that none of the knowledge I've acquired over the past forty years applies to it?

Go ahead, show me one thing I've said here that is outlandish. Show me one objective fact I have argued with. Even in the post you quoted above I agreed with the comment I was replying to. Yet somehow you accuse me of ignoring people. Is English your third language? How does me agreeing with someone mean that I am not listening to them?

The $10-15,000 price quoted for boosting the engine is ridiculous. The engine could be rebuilt for $1,500 easily. Swapping a manual transmission wouldn't add more than $1,000. The programming issue is easily handled by switching over to Megasquirt EFI for a trivial amount of money. There are plenty of Eaton M90 blowers available for as little as $200. The M90 was used on 3.8L engines, so it's the perfect size for the 3.7L. The only complicated part would be mounting the blower since there are no kits available. Yeah, this would all take work... so what? It's hardly the stuff of "video games and dreams".

 

[Senistr]

My post wasn't directed at building a race car. It was a suggestion to get you your "power" that you want. It's more physics than anything. The Jeep weighs X amount and can push Y amount, where Y is = to the power:weight ratio. Now remove Z weight from the Jeep, what is the new power:weight ratio. Removing weight is the fastest way to improve acceleration, which is what you said you originally wanted. Also, making the lighter, stronger parts, the flywheel, and a manual can make shifting faster and easier, creating a faster distribution to the power pushing the Jeep. Pretty common sense to me. The Ethiopian will always run faster than the 400 lbs beast running after the ice cream trucks.

 

[KYLiberty]

Have fun. I'm out. Was just trying to help. Used to have the fastest KJ in the world.

 

[tjkj2002]

Exactly what am I not listening to? What experience? Nobody here has rebuilt an engine with those aftermarket pistons. So nobody here knows if they are better than the stockers. Video games and dreams? I haven't played video games in decades. And NOTHING I have posted here is the stuff of dreams. Rebuilding an engine with beefier parts is basic stuff. Is "video games and dreams" really your go-to insult for a 45-year old man? I did my first brake job when I was five. How many people here have been turning wrenches for four decades? I bet there's only a handful of people here with as much experience as me. Or are you trying to say the KJ is so unique that none of the knowledge I've acquired over the past forty years applies to it?

Go ahead, show me one thing I've said here that is outlandish. Show me one objective fact I have argued with. Even in the post you quoted above I agreed with the comment I was replying to. Yet somehow you accuse me of ignoring people. Is English your third language? How does me agreeing with someone mean that I am not listening to them?

The $10-15,000 price quoted for boosting the engine is ridiculous. The engine could be rebuilt for $1,500 easily. Swapping a manual transmission wouldn't add more than $1,000. The programming issue is easily handled by switching over to Megasquirt EFI for a trivial amount of money. There are plenty of Eaton M90 blowers available for as little as $200. The M90 was used on 3.8L engines, so it's the perfect size for the 3.7L. The only complicated part would be mounting the blower since there are no kits available. Yeah, this would all take work... so what? It's hardly the stuff of "video games and dreams".

Get out of the '80's and '90's thinking.The 3.7 and 4.7 has almost zero aftermarket support.Rebuilding to stock you may get away with $1500 if you do 100% of the work yourself,modding it no way.


You just can't throw another PCM in that is not a OE PCM,if you have antitheft then your stuck gutting all other electronics to make the engine run.Swapping in a manual will cost more then a $1000 and end up with a weaker trans then even the 42RLE.


Having a lower intake made to mount that supercharger from the GM 3.8 would run you $2000+.




Go for it,I want to see it but it will cost you $15K easily to break the 300hp mark,more to make it reliable and legal.

 

[tommudd]

Everyone may as well give up
some come on here due to wanting to meet like minded people with KJs
some come seeking advice and actually listen to what is being said from years of experience
some come just to...............well not sure :happy175:

 

[CactusJacked]

So a swap is an option. But it seems like a lot of work for very little gain. The 4.7 just isn't that much more powerful than the 3.7.

Oh, the differences are far greater than you may think. Here are the specs on both...

3.7:
210 hp @ 5,200 rpm
235 ft. lbs. torque @ 4,000 rpm

4.7:
235 hp @ 4,700 rpm
290 ft. lbs. torque @ 3,700 rpm

So you may be saying, "only 25 more hp?", but that's an apples to oranges comparison. Look where the max h.p. is at, the 3.7 is 500 rpm's higher, which means well beyond the usable range. 4,700 on the 4.7 is still up there, but not as bad.
BUT, torque is the pulling power you feel off the line (acceleration). Not only does the 4.7 have 55 ft. lbs. more, it comes in at a lower rpm; where the engine will easily spend more time.
Translation, the difference in acceleration between the 3.7 and 4.7 would be VERY noticeable.