[MadOTC314]

I bought my car in November, a 96 with about 65K on it. Overall in pretty good shape. I have been collecting parts over the last month, and today I took the plunge and bought the long block from Summit. Here's what I have so far:

Summit Racing™ Chevy LS 5.3L 450HP Long Block Crate Engines SUM-150153
LS6 intake manifold and fuel rails
36 LB Injector Connection Injectors
LS2 Coils
Megasquirt 3 computer
Microsquirt 4L60e controller

I think i'm going to order all the swap parts (engine/transmission mounts, long tube headers, oil pan, front accessories, radiator) from BRP Hot Rods this week. I'll post some pics as soon as the parts start showing up. Wish me luck!

 

[stonebreaker]

Good luck on the build!

 

[Filthy McNasty]

I am excited for you and will be following. I hope to do the same to my 96 RMS sedan. Please keep us posted!

 

[nsaness]

I bought my car in November, a 96 with about 65K on it. Overall in pretty good shape. I have been collecting parts over the last month, and today I took the plunge and bought the long block from Summit. Here's what I have so far:

Summit Racing™ Chevy LS 5.3L 450HP Long Block Crate Engines SUM-150153
LS6 intake manifold and fuel rails
36 LB Injector Connection Injectors
LS2 Coils
Megasquirt 3 computer
Microsquirt 4L60e controller

I think i'm going to order all the swap parts (engine/transmission mounts, long tube headers, oil pan, front accessories, radiator) from BRP Hot Rods this week. I'll post some pics as soon as the parts start showing up. Wish me luck!

Good luck, you should be very happy when you are done! First of all, I love going the LS route, because it is modern, reliable, power that gives room to grow and far more tuning options.
I am excited to follow your journey, and I fully support your decision.

I am curious though, what considerations led you to choosing the LS swap over a 450hp 383 LT1 build? Are you planning for more horsepower in the future, or did you want to dump the LT1 for a particular reason? Thank you.

 

[MadOTC314]

I think the parts availability and the amount of information out there about LS engines really pointed me in that direction. I just felt like I could reach any power level I wanted with that platform, and any problems I ran into, I would be able to find the solution on the internet pretty quickly. I tried setting up that Megasquirt with a SBC a few years ago, and ran into all kinds of problems because of a few oddball things I was trying to do. This time I'm trying to make things as simple as possible.

 

[nsaness]

I think the parts availability and the amount of information out there about LS engines really pointed me in that direction. I just felt like I could reach any power level I wanted with that platform, and any problems I ran into, I would be able to find the solution on the internet pretty quickly. I tried setting up that Megasquirt with a SBC a few years ago, and ran into all kinds of problems because of a few oddball things I was trying to do. This time I'm trying to make things as simple as possible.

Yes, I have had some prior Megasquirt issues myself (on another car). I think it was only due to my ignorance and stupidity.
There are certainly more LS tuners and resources available. It's not cheap, but I know you will love your conversion once its done and the bugs are worked out.

 

[toonwarrior]

I know this is a bit of an ironic question, but how is the fuel mileage on an LT1 stroker versus an LS that makes around the same power.

I like the idea of keeping it OG with the lt1 motor but if it turns into a gas guzzling monster then not sure if I want to go down that route, with cars coming from factory with those hp numbers that seem a lot more efficient I would think that the LS is better but I don't know any better.

Went to a car meet and guy was proudly showing off his high hp muscle car that if he started his car 4-5 times he'd lose like half his tank, not sure how he sees that as a good thing but I definitely do not want my car to be on that path 😂

 

[nsaness]

I know this is a bit of an ironic question, but how is the fuel mileage on an LT1 stroker versus an LS that makes around the same power.

I like the idea of keeping it OG with the lt1 motor but if it turns into a gas guzzling monster then not sure if I want to go down that route, with cars coming from factory with those hp numbers that seem a lot more efficient I would think that the LS is better but I don't know any better.

Went to a car meet and guy was proudly showing off his high hp muscle car that if he started his car 4-5 times he'd lose like half his tank, not sure how he sees that as a good thing but I definitely do not want my car to be on that path 😂

Assuming a good tune on both, it would be interesting to know what miles per gallon a 450hp LT1 gets versus a 450 hp LSX.
Since the OP indicates you can buy a 450hp 5.3l LS engine, and typically an LT1 would want to be 6.2l (383 cu in) to comfortably make 450 hp; this seems to indicate a fuel efficiency advantage for the LS platform.
In my own car, I am finding huge advantages in using the Torhead set up/Gen 3 LS (0411) PCM. I am making far more horsepower and still getting better fuel mileage than I ever did with the old LT1 set up. The ability to tune a forced induction LT1, with the LS PCM, has advantages for sure.

 

[jayoldschool]

@95wagon should be able to provide insight, but I'll bet close to 30mpg is possible with that 5.3, depending on gearing/foot in it/cruise speed...

 

[shakenfake]

Easily LS stroker.

 

[stonebreaker]

The flow on the LS heads is so much better than the old SBC heads that you can make the same power on less cam, meaning better mileage at part throttle.

 

[stonebreaker]

If you're really concerned about fuel economy, you can always get an engine with the cylinder deactivation and the cam advance gizmo, as well.

 

[shakenfake]

VVT is alright
AFM/DOD is garbage and flat out no.

 

[PD939C1]

Love my VVT on my 3.6 Impala and my 6.0 swap. Gas mileage with the 6.0 is better than it was with the 5.7 TBI. So far, 20mpg with a very heavy foot. None have the DOD.

 

[95wagon]

VVT with performance cam + springs great idea until the cam eats the second cam bearing.

Mileage

@95wagon should be able to provide insight.

While there is an L76, LS3, LS7 in the driveway , the first 2 are stock , good enough mileage based on how often they need filling that I have never bothered doing an extensive milage check. Love the cars they are in , milage is not going to change that.
The LS7 has enough cam in it , on 110 , that it has a choppy idle and the resulting poor sub 1500 efficiency.
Stop and go traffic the fuel milage is abysmal. Cruise and highway it would be good if I didn't drive it like someone 50 years younger than me !

 

[Marky Dissod]

In my own car, I am finding huge advantages in using the TorqHead set up / Gen 3 LS (0411) PCM.
I am making far more horsepower and still getting better fuel mileage than I ever did with the old LT1 set up.
The ability to tune a forced induction LT1, with the LS PCM, has advantages for sure.

If you're really concerned about fuel economy, you can always get an engine with the cylinder deactivation and the cam advance gizmo, as well.

GM's half-engine cylinder deactivations were badly designed, at least so far as the real world goes.
Too many livery drivers can tell you that they will never outright buy any GM vehicle with 3- or 4-cylinder mode, as those systems seldom survive the lease period, at least the way most livery drivers drive in NY / NJ / CT.

Biggest underutilized advantage of the 12200411 pcm is the use of a fully enabled and patched Aussie operating system.
Whenever the pcm determines that several conditions are ALL met, Lean Cruise can be permitted.
With the proper gearing, while driving non-enthusiastically, MpG gains equalling or exceeding V4 Mode or VVT are possible.

Before anyone mentions fear of running lean, Lean Cruise was OE in Australia with the 12200411, and suffered less problems than V4 Mode or VVT.

 

[shakenfake]

I have heard of no success stories getting an American PCM to accept lean cruise. For some reason doing the segment swap is near impossible. At least with HPTuners it is impossible, you may have more success with EFI Live but still I don't know anybody that got it working.

If you could find an Aussie PCM and have it shipped over here you could get it to worked but it is completely disabled on American PCMs.

 

[95wagon]

it is completely disabled on American PCMs.

04 GTO ?

 

[Marky Dissod]

I've heard of no success stories getting an American PCM to accept lean cruise.
For some reason doing the segment swap is near impossible.
At least with HPTuners it is impossible.
You may have more success with EFI Live but still I don't know anybody that got it working.

If you could find an Aussie PCM and have it shipped over here you could get it to worked but it is completely disabled on American PCMs.

I know of at least one tuner who turns away customers when they ask for Lean Cruise by name.
I totally understand why - and I will never name the tuner.

I also get HPTuner covering their arses - if they make it too easy, it becomes their quagmire.
Even heard that some of their updates make it more difficult to enable.

Even an Aussie op sys 'checks' to 'make sure' it is 'installed' in a 'Holden' before making Lean Cruise possible.

 

[95wagon]

"
know of at least one tuner who turns away customers when they ask for Lean Cruise by name.
I totally understand why - and I will never name the tuner."

Pardon my take on your statement but it smacks of " I know a secret "

What is HP tuners covering their ass on ?
Pretty much anything you can change in HP Tuners will violate emissions laws.
Also you are able to destroy stuff with a key stroke without having to go near lean cruise.s

Being we are on a 94-96 impala sight , what does the calibration check against ?
No BCM or anything in the car to verify the holden serial you leave in the cal.
Long as that digit is correct it doesn't care does it ?
Vaguely remember there is a work around as well.
Or run the 04 GTO P59 ? .
That all the above with a grain as I am second hand on all this info.