LTG Turbo 2.0 upgrades... Needs/Wants/What to do...
 

Hey guys, I figured I would cross-post this since there doesn't seem to be much posting going on at the Cadillac forum, and since it is the same engine I figure more people here would have some input...

I have a 2014 CTS-4 Performance with about 41k miles on it. Perfect condition. 100% stock.

In doing a bunch of reading it would seem as if the early ones (pre-2016) are complete crapshoots in regards to either being reliable and durable, or just ticking time-bombs in regards to piston failure.

As such, I am trying to decide if I keep the car, and if I do what kind of modifications do I *NEED* to do to make it reliable, and at the same time what mods do I *WANT* to do to make it more enjoyable to drive.

Here is what I figured out I would *NEED* to do to make it reliable:

- Change pistons/rods to forged ones (rods only make sense when you do the pistons) along with properly gapped rings
- Change the PCV system to use the upgraded components offered in the 2019 revisions (PCV valve, vents)
- Clean deposits from the intake valves while the head is off
- Reinstall using new ARP head studs and gaskets

Beyond the above the next are the *WANTS* to make it enjoyable:

- Swap to bigger turbo (either ZZP ZFR or Big Wheel offerings, or Turbobay 72x stage 2)
- E85 conversion kit
- New tune for both the bigger turbo and E85 kit

Now the whole question is, since it is all apart does it make more sense to also change out:

- New cams and springs? (stage 2 from ZZP would be the only consideration)
- Bigger radiator?

Personally I have been doing high performance stuff for over 25 years, including big HP, forced induction stuff (both turbo and supercharger) and know better than to change a lot of stuff people worry about (such as the throttlebody, as there is ZERO power or performance to be had with that mod on a forced induction car), or even doing things like going with a high-flow downpipe unless I was going to get rid of the cat (which I am not), so an aftermarket catted downpipe is only marginally better than the stock catted downpipe, or changing things for pure sound (like the silicone intake tubes, which, since I don't want turbo noise at all, does nothing for me). A larger intercooler makes sense, but no-one makes one to fit the CTS. I may look into building a custom air-water intercooler in the future, but to start I would just use what it comes with stock.

I have not heard of anyone complaining about coolant temps, and it would seem as if lower-temp thermostats are not available for the LTG engines so there is nothing to be gained by lowering coolant temps until they become available.

So, to sum it up, I am looking at doing a forged bottom end, bigger turbo, E85 and possibly cams?

If I keep the car I am planning on doing a brake upgrade (I have the stock 19" polished aluminum wheels and the dusting from the stock semi-metallic brake pads is gross) as well.

I love the handling and looks of the car. I don't drive it as much as I would like because it feels somewhat anemic. I think a nice bump in power would make it fun to drive more. Something around 380hp to 400hp or so range would be great.

I would be doing the engine pulling, disassembly, reassembly and installation. I would look to either ZZP or Trifecta for a tune (ZZP if I put on their turbo and cams, Trifecta if I put on a Turbobay turbo and skipped the cams). So, budget-wise I am looking at $1400 or so for the NEED to do's, $1750 for the Turbobay/E85/Tune through $4500 or so for the ZZP ZFR turbo/E85/Cams/Valvesprings/Tune.

Beyond all of that I am still using the stock 6l45 transmission, so would I be better off going with a new Sonnax valvebody to replace the stock one? I know they upgraded a bunch of stuff compared to the stock 6l45 valvebody and would be looking for durability and longevity more than anything else.

So, overall I am looking at $3000-6000 as the range for upgrades. Again, I am not looking to change the sound of car to anything outrageous (no turbo noise, no exhaust changes, outside whatever the cams would do if I went with them) and overall just want a broader powerband with more power overall.

I love the fact there is Tour/Sport/Winter modes and basically would probably want to leave Winter mode limited, with Tour mode only slightly enhanced at WOT and Sport mode being where the true fun is.

Any and all input would be appreciated.

Oh, I forgot to mention, I would probably end up going with one of the better PCV catch can system offerings as well.

I forgot to mention, I am one of the f-body faithful, as I still have a 1995 Trans-Am and a 1995 Camaro Z28 convertible. Both are heavily modified (of course). Performance-wise they both have 383 LT1s, superchargers/aftercoolers, T56 manuals, etc...

I think that you're doing a disservice to yourself by writing off the downpipe and intake. ZZP catted downpipe, ZZP silicone intake tube, K&N high-flow air filter, and the BNR (JacFab) recirc. valve made a huge difference. Made my car more responsive and changed the way boost was held (more and longer into the power curve).

That is the whole point, in that if I want speed/power I have a couple other cars to drive...

The T/A is just over 1000hp on boost alone and the convertible is around 750hp... Both on 93 octane with no methanol or anything else. Both are dual disc clutch and fully built suspensions and all the rest to make them complete cars.

The CTS4 is just more refined. Again, not looking for sound or turbo whistle or all out speed... I just want it to be less anemic.

My Lincoln MKS is over 300hp (non-turbo version, but is a prototype that has the Mustang variant of the engine that is normally 275hp) so it has decent torque and horsepower, and my Lincoln MKT Town Car is just around 300hp, but as a livery-spec vehicle it is tuned way different than the consumer-version with effortless throttle and handling (it was tuned that way for livery drivers that are in the car for extended time, as it is less fatiguing, but there is a lot less "feedback" for the driver), again non-turbo, and both of them are more "likeable" driving wise due to the fact they have more HP and torque in general than the CTS.

Also, not worried about sell-ability, I keep my cars long-term. Thus why durability and reliability are foremost for me.

I bought the CTS4 because it handled great, had all the bells and whistles, the interior is fantastic and in general I could justify it even as an "emergency winter vehicle" if I needed to drive it in winter. Outside of the T/A, Z28 and the Mustang in the family, all the rest of the vehicles are AWD or 4WD.

I am prolly the only one on here and fb that has gone this far with ltg gen6 @ 13k #2 car. You are welcome to take it for what it's worth. My feeling says if you haven't popped any internals leaning to the money savings side. My strategy is to get the bang for the buck and use the W/M system to do its job. I just measured my daughter's Jeep jk exhaust at 800 f troubleshooting the blessed P2096 code. Ltg runs 1800 easily in racing. E85 runs even hotter on get after a set amount. But leaning toward the logical practices that make sense. The billet wheel will get you into the vt tables to extend the cursed Max tq curve. Give it air flow and a chance to stay cool it will be what you are looking for cause that was my exact goal. Even the lt4 come with hiptectic Al pistons so it's more in how you treat it. I've seen some crazy logs out there so it's just not supposed to be that hard. And it's not that hard to get a good dd response that you will enjoy. No need to over do it but the parts aren't cheap but prolly in your wheelhouse.

Following this thread for info. Just got me a 2016 2LT RS last night and I want to do a few upgrades myself, although I am not going quite as far as you are. LOL

Well, small followup...

Turns out I will be getting my experience in working on Ecotec engines, as my father had his 2.4l LEA engine go on his 2012 GMC Terrain and I am going to be replacing the pistons and cylinder head along with the timing chain and balance shaft chain and even the waterpump on his in the next few weeks.

Basically the LTG is the turbo version of those motors, so, depending on how difficult it is to do I will know exactly what I am getting myself into on the LTG in my 2014 CTS4. So the only big difference is the way the engine sits in the engine bay.

Neat. I haven't broken into a car motor yet it seems like a great learning experience.

Quick follow-up...

I ended up ordering up a ZZPerformance Big Wheel turbo unit, as well as the Trifecta Elite upgrade package to support the tuning changes for it.

It will be a while until I can get it installed, I have quite a bit on my plate for the foreseeable future, but I will get to it before spring.

E85 is what all the ricer boi's turned LTG zealots use to get their jollies off. The big wheel throws a lot of air at good pressure. Good balance. Safe, easy to tune. You can swap it in an afternoon but you wont get any noticeable increase without a bump in the torque tables. There's some secret sauce to reaching the alto section of the air use but I digress. You will want a get another mod, which is my MW injection kit ($) that STM ghosted on. Cooled air at boost.

Please Wook, do not attempt to negate the positive effects of E85 on a FI, small displacement, VVT car.. Its an injustice to the community..


Im FAR from a "ricer" Fact is, this is my first 4-cylinder. YET.... It will GAP 80%+ of whats on the road today.

Hello everyone. I'm new to this forum. My wife has a 2016 ATS. I am not a ricer import guy by any means. For the last 30 years of racing I have always been a Big Block Buick, Pontiac, Olds, Cadillac and Ford kind of guy. All of those were always aided with a heavy dose of Nitrous. This is our first experience with a 4 cylinder and a turbo. I bought her the car because it was a smaller sized 4 dr luxury Black Cadillac.

After driving the car I said honey this car is pretty fun to drive isn't it. She uses it as a daily (1 1/2 miles each way to work) driver. So we got her car done at ZZP as a 30 yr. Wedding anniversary gift to her. It now has a ZZP forged bottom end, ATI balancer, stage 3 cams, valve springs, head studs, intercooler, larger throttle body, throttle body spacer ( for possibly a small wet shot of nitrous) , catted downpipe, E85 conversion and a Borg Warner 6758 EFR turbocharger

The car has a conservative Turbo Tim tune in it for now. On General G-MAX RS 255/40ZR17 on the rear and 225/45ZR -17 on the front, the car has been 12.012 @ 116.84

https://www.dropbox.com/sc/84t31cjmf...7LY4VfU5I5FPGa

We want to make some up grades to the suspension before putting on a better set of rear tires.

Hey guys, new to this forum. I own a 2019 1lt with catback exhaust, magna flow glass packs, CAI, catless downpipe and I tuned it right after. Next im adding a upgraded intercooler to help keep it all cool.