LS swap update and questions

[Longhorn84]

I realize this is a bit nuanced since I am talking LS swap but it's been 5 years and I just made an update video on YT and thought I would ask opinions here. My stock 5.3 LS with the 4l60e and 4.56 gears is not as peppy as I thought it would be. Sure, it's quicker than the 4.0 but for all the work I put into it, I was hoping for more. I'm considering a more aggressive cam, higher stall torque converter, a professional tune, and potentially a regear (5.13's?). I don't rock crawl, don't drive long distances on the highway, this is a fun toy around the city with my kids, it's nostalgic for me so right now I'm just looking for on-road manners. If you were me, what would you do to bump up the quickness (I don't care about gas mileage)? I'm still super envious of the 392 crowd, I know I can't get there in terms of performance on my set up but I feel like I can bridge the gap with some tweaks.

 

[Apparition]

Drop in a 6.2.

 

[lBasket]

I realize this is a bit nuanced since I am talking LS swap but it's been 5 years and I just made an update video on YT and thought I would ask opinions here. My stock 5.3 LS with the 4l60e and 4.56 gears is not as peppy as I thought it would be. Sure, it's quicker than the 4.0 but for all the work I put into it, I was hoping for more. I'm considering a more aggressive cam, higher stall torque converter, a professional tune, and potentially a regear (5.13's?). I don't rock crawl, don't drive long distances on the highway, this is a fun toy around the city with my kids, it's nostalgic for me so right now I'm just looking for on-road manners. If you were me, what would you do to bump up the quickness (I don't care about gas mileage)? I'm still super envious of the 392 crowd, I know I can't get there in terms of performance on my set up but I feel like I can bridge the gap with some tweaks.

Where is the torque peak for the 5.3 it's relatively high on the LS isn't it. Go look at the Grimmjeeper calc to see if different gears will put you there at the speed you want?

Or are you just trying to light up the tires from a stop

 

[Longhorn84]

Drop in a 6.2.

I've thought about it for sure! but then the can of worms on trans breaking and rear axle not being able to handle, would probably have to go to 6l80 and beef up the rear axle and at that point I'd probably start over with a lower mileage LJ.

 

[Apparition]

https://www.motortrend.com/how-to/1905-how-to-easily-gain-100-horsepower-on-a-5-3l-ls-engine

 

[Longhorn84]

Where is the torque peak for the 5.3 it's relatively high on the LS isn't it. Go look at the Grimmjeeper calc to see if different gears will put you there at the speed you want?

Or are you just trying to light up the tires from a stop

It feels like the torque really starts around 2,200 from a dead stop, it's just that I think a pacifica minivan could beat me off the line. So, yes, the ability to light up the tires from a stop would be a good place to start. I've thought about taking it to a shop around town to get advice but I figured I would start here.

 

[lBasket]

View attachment 634973
View attachment 634972

https://www.motortrend.com/how-to/1905-how-to-easily-gain-100-horsepower-on-a-5-3l-ls-engine

Carb going backwards

 

[Longhorn84]

View attachment 634973
View attachment 634972

https://www.motortrend.com/how-to/1905-how-to-easily-gain-100-horsepower-on-a-5-3l-ls-engine

I'm not sure if it's just a HP question but it also seems like stall and gearing would help?

 

[lBasket]

It feels like the torque really starts around 2,200 from a dead stop, it's just that I think a pacifica minivan could beat me off the line. So, yes, the ability to light up the tires from a stop would be a good place to start. I've thought about taking it to a shop around town to get advice but I figured I would start here.

Doesnt different stall converters effect this? I don't know exactly what they do really

 

[Apparition]

Carb going backwards

They go fuel injection in part 2 but I'm not having any luck finding it.

 

[lBasket]

They go fuel injection in part 2 but I'm not finding it.

Take a step backwards to make your step forwards look better... Nice

 

[Wildman]

I realize this is a bit nuanced since I am talking LS swap but it's been 5 years and I just made an update video on YT and thought I would ask opinions here. My stock 5.3 LS with the 4l60e and 4.56 gears is not as peppy as I thought it would be. Sure, it's quicker than the 4.0 but for all the work I put into it, I was hoping for more. I'm considering a more aggressive cam, higher stall torque converter, a professional tune, and potentially a regear (5.13's?). I don't rock crawl, don't drive long distances on the highway, this is a fun toy around the city with my kids, it's nostalgic for me so right now I'm just looking for on-road manners. If you were me, what would you do to bump up the quickness (I don't care about gas mileage)? I'm still super envious of the 392 crowd, I know I can't get there in terms of performance on my set up but I feel like I can bridge the gap with some tweaks.

Can't comment on LS stuff since I've only owned one and I was wholly unimpressed with it... But it was a 6.0 in a Chevy 2500 pickup...


I did my first swap in 2006 & it was a 5.2 (318) Dodge Magnum V-8 and I was equally unimpressed with power that it had. Thought there were issues with my drivetrain and the shop that had done my swap blamed the STaK's t-case all the time. I have 5.13 gears & started on 35" tires and then swapped in 38" tires. Off-road it was fine when in low range but then so was the 4 cylinder.

First off I'd verify that your engine is in good condition, Leak Down Test & Compression Test. Then I'd get a GOOD TUNE from a reparable shop. Then I'd start on engine mods like a torquer cam. Can you change rocker ratio? Id do all this before messing with the torque converter. Also can't you tune your transmission?

I'd built a stroker 5.9 making it a 6.7 (408) that I only drove for a few trips but due to a machine shop screw up the block cracked.

So then I swapped in a Gen III 5.7 Hemi & 545RFE. It's a 03 5.7 so had the pre-Eagle heads that were known for dropping valve seats. So I installed Eagle heads & a Hellfire 2.0 cam from FRP. So far I can tell you there is a HUGE difference between how the Magnum engine responded and then how the Hemi does.

 

[Longhorn84]

Can't comment on LS stuff since I've only owned one and I was wholly unimpressed with it... But it was a 6.0 in a Chevy 2500 pickup...


I did my first swap in 2006 & it was a 5.2 (318) Dodge Magnum V-8 and I was equally unimpressed with power that it had. Thought there were issues with my drivetrain and the shop that had done my swap blamed the STaK's t-case all the time. I have 5.13 gears & started on 35" tires and then swapped in 38" tires. Off-road it was fine when in low range but then so was the 4 cylinder.

First off I'd verify that your engine is in good condition, Leak Down Test & Compression Test. Then I'd get a GOOD TUNE from a reparable shop. Then I'd start on engine mods like a torquer cam. Can you change rocker ratio? Id do all this before messing with the torque converter. Also can't you tune your transmission?

I'd built a stroker 5.9 making it a 6.7 (408) that I only drove for a few trips but due to a machine shop screw up the block cracked.

So then I swapped in a Gen III 5.7 Hemi & 545RFE. It's a 03 5.7 so had the pre-Eagle heads that were known for dropping valve seats. So I installed Eagle heads & a Hellfire 2.0 cam from FRP. So far I can tell you there is a HUGE difference between how the Magnum engine responded and then how the Hemi does.

Good ideas for sure, thank you for the advice!

 

[Wildman]

Good ideas for sure, thank you for the advice!

Trying to save you money....

I would think from things others have said that have a 4.8 or 5.3 in their rigs that some simple mods should get you the HP & TQ you're looking for.

My 5.2 turned out to have a cracked head on the exhaust seat. This is why I'd suggest making positive that your engine is 100% before doing anything else to it.

This is my untuned 5.7 Hemi. 38x13.5x17 M/T Baja Pro XS tires on 9x17 SpyderLocks & 5.13 gears.

I haven't tried to smoke my tires or do burnouts (they cost too much now) but I know I could when I had the 5.2 Magnum.

 

[5632]

My TJ with a 5.3 LS and 4L60E is absolutely fantastic. Power, torque and handling. It's hard to believe how many Teslas I upset.

 

[Longhorn84]

Trying to save you money....

I would think from things others have said that have a 4.8 or 5.3 in their rigs that some simple mods should get you the HP & TQ you're looking for.

My 5.2 turned out to have a cracked head on the exhaust seat. This is why I'd suggest making positive that your engine is 100% before doing anything else to it.

This is my untuned 5.7 Hemi. 38x13.5x17 M/T Baja Pro XS tires on 9x17 SpyderLocks & 5.13 gears.

I haven't tried to smoke my tires or do burnouts (they cost too much now) but I know I could when I had the 5.2 Magnum.

That has way better response for sure, I'd be thrilled with that performance, what trans/stall combo?

 

[Wildman]

That has way better response for sure, I'd be thrilled with that performance, what trans/stall combo?

545RFE & stock torque converter. I have no idea what it's stall speed is.

Edit: Watching your video & I'm SHOCKED you haven't broken your Dana 35 yet. I knew guys with 5.2 or 5.9 Magnums that broke their Dana 35's within a year of the V-8 swap.

 

[Longhorn84]

Trying to save you money....

I would think from things others have said that have a 4.8 or 5.3 in their rigs that some simple mods should get you the HP & TQ you're looking for.

My 5.2 turned out to have a cracked head on the exhaust seat. This is why I'd suggest making positive that your engine is 100% before doing anything else to it.

This is my untuned 5.7 Hemi. 38x13.5x17 M/T Baja Pro XS tires on 9x17 SpyderLocks & 5.13 gears.

I haven't tried to smoke my tires or do burnouts (they cost too much now) but I know I could when I had the 5.2 Magnum.

here's some driving footage.

 

[Longhorn84]

My TJ with a 5.3 LS and 4L60E is absolutely fantastic. Power, torque and handling. It's hard to believe how many Teslas I upset.

If true that's encouraging, any work to the 5.3 and what stall and gears do you have? professional tune? drive by wire or drive by cable?

 

[Longhorn84]

545RFE & stock torque converter. I have no idea what it's stall speed is.

Edit: Watching your video & I'm SHOCKED you haven't broken your Dana 35 yet. I knew guys with 5.2 or 5.9 Magnums that broke their Dana 35's within a year of the V-8 swap.

Me too, maybe it has to do with whatever the powertrain / HP loss isn't sending to the axle. If I break it then I really have to decide on a regear, wondering if 4.88 or 5.13 would be a better combo for my setup.