Howdy yall. Trying to map out my plan before executing.

Planning to put an LS1 in my 04 Porsche 911/996 6-speed manual. It has a blown M96 3.6Lengine and I'm going LS. (Haters and purists can stop reading now, I'm moving forward! hehe). Anyway, I just received my Renegade Hybrids complete conversion kit to perform the swap. Also, there is a plug and play engine harness by Chavis Performance that I plan to buy which connects directly to the round Porsche main body harness connectors and utilizes the E38 PCM from a Gen IV engine. It is basically a Gen IV engine standalone harness with factory connectors and with provisions to sprechen sie dueutsch so that the 911 gauges and instrumentation works while the E38 manages the engine.....it's a pretty sweet setup. Only issue is that I have to convert my LS1 into a "Gen IV" engine. MY LS1 is going to get a rebuild anyway, so I planned to make the following changes. Can someone please tell me if these steps will lead me to Gen IV imposter status?

1. Change 24X reluctor wheel to 58X GM # 12586768
2. Change cam shaft gear to 4X GM # 12591689 (1 bolt style) or 12586481.(3 bolt style)
3. Buy knock sensors from Gen IV engine and relocate them to the sides of the block
4. Buy E38 PCM

I think that's all I will need to do to turn my LS1 into a Gen IV that will run using a Gen IV harness and computer. I realize I can just sell the LS1 and buy a Gen IV, but I have the LS1 and most of the rebuild parts, plus aluminum Gen IVs 6.0 and 6.2s are getting way more expensive and HARD TO FIND these days. I want an aluminum block so that the weight remains the same.as the original engine (actually 20-40 lbs lighter).
I also plan to use an LS6 Cam, LS6 intake and injectors plus ported and polished 241 heads that will be decked just a bit to try to get it close to 400 CHP..
Am I way off here? Not worth the risk? Has anyone actually done this successfully?
Thanks in advance for any feedback!

 

You will need a tune, so get a different cam. Otherwise the plan sounds good.

 

When I talked to Chavis, they indicated that there are boundaries on what will work with their harness.
They would be the best source most likely since their part is critical to make it all work.

The engine I've wanted to see tried is a late model aluminum DI 4.3 if only there was a harness for it.
similar power to a Porsche engine but not as tight of a fit. And with the right adders would be way more power than stock. and even lighter..
Would be real sweet with a right sized twin turbo kit.

I'm mid install on a new motor in my 996. Jacked my right arm up a bit and its really slowing me down..

 

Thanks! I was planning on using an LS6 Cam. That should work, eh?

 

Thanks for the feedback. Yes, I realize they are mostly focused on LS Gen IVs, but I'm pretty sure this strategy will make it all work out,

The 4.3 is a good little engine and probably does not require nearly as much cutting. I plan on going NA to simplify things and make it as reliable as I can. I want to be able to drive this everyday.

Sorry to hear about your arm, hope you're able to get back on the project soon. Best of luck!

 

Sort of. It's on a different base circle, so just like an aftermarket cam you'll want to check pushrod length (which will likely have to change). But the LS6 cam is not a great cam. You can find plenty of aftermarket choices that have both better low-end torque and still make the same peak hp (much more total area under the curve). Or you can find many that have the same low-end, but make a lot more hp. And especially with ported heads, you're leaving a lot on the table with the LS6 cam.

 

Let us know about how much you think it's The car is going to weigh along with what transmission you are using (helpful to know the trans gear ratios as well) and what final drive ratio you have as well as your tire diameter, then try to estimate your ideal cruising RPM if you're interested at all in economy we can talk about something mild like an LS6 cam though there lots of mild profiles available (you'll make more average torque and horsepower than with the Ls6 cam but still a mild idle) that work with the same OEM reliable springs. Better yet still there are lots of wilder profiles that will still work with the same LS6 springs. I guess you can tell I'm a big fan of LS6 springs.

 

You know what works, and has been proven, for close to 20 years now. And the price is right. Why change?

 

Was waiting for the OP to weigh in on the vehicle specs, but since he hasn't returned, I'll throw this out there. If I'm right, the car should be around 3000lb, the transaxle gearing is pretty short http://www.gboxweb.com/996specs.html, and tires around 25" tall.

If he's running shorties in the swap, I'd go with the Summit Ghost Cam (8715R1). And if he's running long tubes, step up to the Stage 2 8707R1. Get some duration and lift and springs to spin that baby up to 7k like a Porsche chassis loves, and let those ported heads eat.

 

The exhaust on most 911 swaps end up being convoluted enough that IMHO a set of c6/ls2-ls3 manifolds and connect the stock (ish) exhaust..
the design has little back pressure and will support cats and such.. (if needed.)

They are about 3150-3275 depending on trim. My C4 is 3275 stock with convertable+hardtop.

I think the big item is the Chavis system to make the motor work with teh factory dash, it only supports 1 computer..
So the engine cant do anything the computer can't and you have to be careful not to change the traffic on the CAN buss much.

 

Sorry fellas. Been busy with kids back to school and kid sports…
Anyway, the 996 will retain its factory G96/01 gearbox, so since it’s a C2……Gear ratios:

1st gear: 3.82

2nd gear: 2.20

3rd gear: 1.52

4th gear: 1.22

5th gear: 1.02

6th gear: 0.84

Ring and pinion: 3.44

i hear that the conversion using the stock gear ratios will leave me with around 3000 rpm at 70 mph. Not sure if I can do much about that without major rework, which I don’t want to do.
Anyway, I know it has 20” wheels and new pirellis but the car’s in storage so I can’t check the size right now, but I would guess they’re 1” taller than factory, which might help my gearing out a bit.

Also, exhaust is fabspeed cat delete exhaust, was hoping to reuse the exhaust and refabricating what I have to.thanks for the suggestion on the cams, I’ll check them out.

One new development, I am now seriously considering buying a new crate ls3 430 after selling another big project. Just curious what y’all’s take would be on going with the 495 vs 430 ls3. I know the stock 996 cooling system does an ok job for a stock ls3, but should I be worried about going with the hot cam? Does the cooling requirement significantly increase?Probably a question more suited for a Porsche swap site, but figured I’d ask since there seems to be sone swappers chiming in. I also am looking for an everyday driver that I can tolerate for long distances and as much as I love the rumble of an LS, a fairly smooth idle and low interior noise at cruise speeds is what I desire. Tempted to get the 495 but I don’t want to deal with overheating issues and a C2 that sounds a bit like a drag car at idle.

Thanks again in advance for your responses. I really appreciate your thoughtful replies.