XJ engine swap feasability

[Dr. Dyno]

We're allowed to use different mounting brackets but we're not allowed to modify the mounts on the frame.

 

[Boostwerks.com]

Re: 3.5l engine swap feasability

These modern turbo I4's are not such the high rpm engines like the old school stuff. If my S2000 had the power range of the Audi I never would have gotten rid of it. Expect the same of the GM.

Dyno plots?

Agreed 100%.

Peak HP and TQ numbers look great when you compare them on paper. However, where they make those peak numbers in the RPM band will be substantially different. Also take into account that your drive train gear ratios have been matched to the factory's low RPM torque band. You may find that to use 5th gear at all, requires 5.39+ gears for example.

I'm not sure what motor you would be swapping out, but you will more than likely be very upset that you spent so much $/time/effort to swap a 200hp I6 for a 200hp I4.

Personally, the ONLY 4 cylinder I would ever swap into a jeep would be a 1.9 TDI with a garrett turbo upgrade.

 

[yossarian19]

Really? The 2.0 turbo makes 260 ft lbs from 1700 on up to 5600 RPM. A new MAF (or was it MAP?) package & an ECM tune makes it 340 ft lbs.
At idle it might not be any match for the 4.0, so maybe not as good a crawler's motor without extra low-range gear reduction to get the RPM where you want them.
For my use, it would be just splendid. I mean, who doesn't want to lose 300 lbs up front & gain 100 ft-lbs in the driving RPM range?

 

[RedHeep]

Re: 3.5l engine swap feasability

Agreed 100%.

Peak HP and TQ numbers look great when you compare them on paper. However, where they make those peak numbers in the RPM band will be substantially different. Also take into account that your drive train gear ratios have been matched to the factory's low RPM torque band. You may find that to use 5th gear at all, requires 5.39+ gears for example.

I'm not sure what motor you would be swapping out, but you will more than likely be very upset that you spent so much $/time/effort to swap a 200hp I6 for a 200hp I4.

Personally, the ONLY 4 cylinder I would ever swap into a jeep would be a 1.9 TDI with a garrett turbo upgrade.

Before you jump in and type about how you wouldn't, do some research and find a dyno sheet. The reason we're talking about using the LNF turbo motor is specifically because the turbo moves the torque curve back into the usable rpm range. The NA ecotecs have a traditional 4 cyl torque curve at a higher rpm.

These engines reliably make 260/260 from the factory at 300 lbs less than an iron jeep 4.0. It's not a honda race motor that needs 7000 rpm to produce power.

 

[shortxjdoug]

We're allowed to use different mounting brackets but we're not allowed to modify the mounts on the frame.

What?

 

[RedHeep]

What?

Ever been to his website?

He's somewhere around the UAE I believe.

 

[87manche]

We're allowed to use different mounting brackets but we're not allowed to modify the mounts on the frame.

that sucks.

you could probably make it work sice the lnf has flat pads, but it's gonna be janky because you'll have 2 ft long brackets to go to the motor.

 

[87manche]

Agreed 100%.

Personally, the ONLY 4 cylinder I would ever swap into a jeep would be a 1.9 TDI with a garrett turbo upgrade.

yes, because a 1.9l diesel with a narrow usable RPM band that makes 150HP is such an awesome choice. Then in order to bring it up to the 300hp an ecotec makes with just a tune, I'm gonna throw a thousand dollars at it's turbo, and since I'm now running out of fueling I'm gonna do fawesome new injectors, and then rework the IP with fat plungers. All so I can avoid swapping a lame 4 banger and make the internets love me....

 

[Boostwerks.com]

Really? The 2.0 turbo makes 260 ft lbs from 1700 on up to 5600 RPM. A new MAF (or was it MAP?) package & an ECM tune makes it 340 ft lbs.
At idle it might not be any match for the 4.0, so maybe not as good a crawler's motor without extra low-range gear reduction to get the RPM where you want them.
For my use, it would be just splendid. I mean, who doesn't want to lose 300 lbs up front & gain 100 ft-lbs in the driving RPM range?

PLEASE show me this graph! 260ft/lbs at 1700RPM? Are you sure it's not a plot of an LS1?

Before you jump in and type about how you wouldn't, do some research and find a dyno sheet. The reason we're talking about using the LNF turbo motor is specifically because the turbo moves the torque curve back into the usable rpm range. The NA ecotecs have a traditional 4 cyl torque curve at a higher rpm.

These engines reliably make 260/260 from the factory at 300 lbs less than an iron jeep 4.0. It's not a honda race motor that needs 7000 rpm to produce power.

Blah. I could go on and on about my history with turbocharged 4 cylinders, but just keep in mind that a FI motor requires a 12:1 AFR when under boost. Combine the fact that the XJ will require more torque to maintain any given speed compared to the FWD passenger car the motor came out of. In other words, you will use substantially more fuel and throttle position to achieve the same amount of power. But, then again what do I know.

yes, because a 1.9l diesel with a narrow usable RPM band that makes 150HP is such an awesome choice. Then in order to bring it up to the 300hp an ecotec makes with just a tune, I'm gonna throw a thousand dollars at it's turbo, and since I'm now running out of fueling I'm gonna do fawesome new injectors, and then rework the IP with fat plungers. All so I can avoid swapping a lame 4 banger and make the internets love me....

I guess you've never heard of HPA? A company that actually specializes in TDI Jeep conversions. 1.9L's of fawesome that can actually produce 300 ft/lbs before 2000 rpm + 30+MPG.

www.hpamotorsport.com

 

[RedHeep]

Can we all get past the I know more than you and why you shouldn't do this and start on the let's figure out how to do it and see if it works plan?

It's really disenheartened to feel like you can't suggest anything new around here without people (including a vendor that sells his own turbo conversion) trying to tell you it will never work without any real proof. I'd much rather rely on their expertise to make it happen rather than fight about why it won't.

 

[MoparManiac]

Can we all get past the I know more than you and why you shouldn't do this and start on the let's figure out how to do it and see if it works plan?

It's really disenheartened to feel like you can't suggest anything new around here without people (including a vendor that sells his own turbo conversion) trying to tell you it will never work without any real proof. I'd much rather rely on their expertise to make it happen rather than fight about why it won't.

It has nothing to do with not being able to suggest something new, and everything to do with people giving you their opinion on it.

What expertise do you need? You already said that there are engine management options and people have stated all you need to do is fab motor mounts and drop the thing in.

Honestly, if you want to do it just do it. I started telling people about dropping a 440 in my MJ and plenty of people told me it either couldn't be done or was stupid. I still did it.

 

[RedHeep]

It has nothing to do with not being able to suggest something new, and everything to do with people giving you their opinion on it.

What expertise do you need? You already said that there are engine management options and people have stated all you need to do is fab motor mounts and drop the thing in.

Honestly, if you want to do it just do it. I started telling people about dropping a 440 in my MJ and plenty of people told me it either couldn't be done or was stupid. I still did it.

Honestly, I don't need anything. We could have closed this thread 2 weeks ago. What I need is $3000 and a couple weekends. Until I save up for that, everything we're talking about is moot.

When a vendor with a ton of self proclaimed turbo knowledge jumps in, you'd like to hear him talk about what you'd need to do to make the power more usable if he thinks it's not. Not get told that it simply won't work. Otherwise, he could just not say anything at all. :cheers:

 

[Boostwerks.com]

Can we all get past the I know more than you and why you shouldn't do this and start on the let's figure out how to do it and see if it works plan?

It's really disenheartened to feel like you can't suggest anything new around here without people (including a vendor that sells his own turbo conversion) trying to tell you it will never work without any real proof. I'd much rather rely on their expertise to make it happen rather than fight about why it won't.

I'm not at all saying that it won't work! Your putting words in my mouth. All I'm saying is that you will more than likely be disappointed with the results. Maybe less however if you'd be swapping out the factory 4cyl.

There is a lot of simply bad information in this thread (hence the reason why I posted).

For a light weight street driven rig, I'm sure the motor would be fine!

I say go for it! :cheers:

 

[Boostwerks.com]

Honestly, I don't need anything. We could have closed this thread 2 weeks ago. What I need is $3000 and a couple weekends. Until I save up for that, everything we're talking about is moot.

When a vendor with a ton of self proclaimed turbo knowledge jumps in, you'd like to hear him talk about what you'd need to do to make the power more usable if he thinks it's not. Not get told that it simply won't work. Otherwise, he could just not say anything at all. :cheers:

Then why post?

I'm not going to lie and try and sell you on to something that I think you may end up being disappointed with! I am however going to express my opinion.

But, in the end it's your money, your time. :thumbup:

 

[87manche]

I guess you've never heard of HPA? A company that actually specializes in TDI Jeep conversions. 1.9L's of fawesome that can actually produce 300 ft/lbs before 2000 rpm + 30+MPG.

www.hpamotorsport.com

yes, lets become dependent on a single company for everything, rather than use OEM parts.

and exactly how much money did they toss at a TDI to get those numbers?
Feed a STOCK LNF engine with a STOCK turbo e85 and a tune and it does this

yes, that's 400HP and 300 ft lbs of torque @ 4 grand.
his uncorrected numbers were 294/369
and the only changes to his car were a new downpipe, catless exhaust and an open filter intake.
he's still putting down over 300HP with 91 octane.

 

[Hoooper]

^^ Actually that curve says 425 lb ft and 320 HP at 4k RPM. Something seems wrong with that curve, ive never seen such a horrible torque curve on a gas engine. Would be weird to ride in a car that revs to 7k, but accelerates harder from 3500-5000 than it does from 5500 to 7000. Maybe the turbo is just huffing and puffing by 5k and that car is going to burn through a lot of turbos?

 

[87manche]

it's a stock turbo with nothing more than a K&N intake and a downpipe.

so yeah, he's probably running up against the limit of what the turbo can do at hgh rpms.
still, the stock setup bolts to a jeep trans and makes those kind of numbers with nothing more than a tune and a different exhaust. Since it would be shoved into an XJ You can plan on sneeding a different downpipe and exhaust anyway.

 

[Hoooper]

it's a stock turbo with nothing more than a K&N intake and a downpipe.

so yeah, he's probably running up against the limit of what the turbo can do at hgh rpms.
still, the stock setup bolts to a jeep trans and makes those kind of numbers with nothing more than a tune and a different exhaust. Since it would be shoved into an XJ You can plan on sneeding a different downpipe and exhaust anyway.

not saying I dont like it, but I would pass on that tune without a bigger turbo. Thats a "my turbo overheated and took out my engine" kind of curve.

Here is a stock dyno. Not nearly as exciting or nearly catastrophic as the other dyno. Not seeing anything about 260 WTQ at 1700 RPM still, but hey 165 at 1700 isnt too bad either.