BoxsterLS376 introduction - LS3 conversion :)

[Pdwight]

What do they do for the exhaust system ?

[Dlirium]

Originally Posted by Topless

Fun project! Scott is a friend of mine and he has done a bunch of 996/986 conversions now. The chassis is talking to the motor just fine on them so you should have no problem with that. Toyota 12v PS and WP are the only way to go. The LS3 is certainly a tight fit but doable and it is a sweet powerplant with monstrous torque.

You may be able to use a Cayman engine cover to fit over your intake. It is a little taller and some have done this successfully. Forget a plexi cover. The way a Boxster breathes by pulling air up from the road surface makes the engine compartment look like a nasty chicken coop after about a week of driving. It ain't pretty and this is actually part of the ground effect in addition to cooling the accessories, trans and rear brakes.

I have considered this conversion but Nazi emissions regs in Comiefornia make a street conversion risky. I would have to register the car at Scott's house in NV and run the CHP impound gauntlet while living here in CA. Too much PITA for me unless it was a dedicated track car.

Exactly my thoughts for CA. I still think that if I blow my 3.2, this would be the best route. make it a dedicated track car and have a blast..

[Dlirium]

Originally Posted by jaykay

How is the drivability and handling of the Boxster with the LS3 if I may ask.......I guess one feathers the throttle to get back to where it was originally as far as traction and balance....would you need a huge leep / amount of seat time to handle it? Have wheel widths been changed..square? I have been on track in a Cayman R (I think the engine was stock) and found that to have just an insane amount of momentum.....well it was the old Mosport, lots green and yellow traffic, R comps....anyway it felt way way over my head even in the power department.

It is amazing. All the standard handling that you get with a mid-engine Boxster, but now you have the power to pull out of corners or kick the backend out. Yes, you can now get yourself in a LOT of trouble, so throttle management will be key. And shifts come a lot quicker :-)

While I don't have this (yet), I have ridden in Scott's car in a spirited drive around Las Vegas...

[Pdwight]

But this is a lot of "stuff" to stuff up the butt of a Boxster

[Qmulus]

Originally Posted by Pdwight

But this is a lot of "stuff" to stuff up the butt of a Boxster

Well, that is an Audi V8 along with an automatic, not a Chevy LSx. Audi V8s are pretty short, and will bolt up to the Boxster transmission with the right flywheel, so you may not have the same issues with the firewall that you do with the Chevy LSx.

Integration of the Audi engine with the Porsche electronics is actually pretty easy. Likely even easier than the Chevy, even with the GM Performance engine harness and ECU. I just so happen the proper engine ECU for V8 with manual transmission and no immobilizer sitting on my desk as I type this. You just have to make sure to get the right engine. You would want the 40 valve 4.2 from an '02-'03 A6, S6, A8 or S8 with the Bosch ME 7.1.1 ECU. The S cars will have a bit more hp. Those engines are also pretty light and I would bet you could use the AC compressor and power steering pump as is on the Audi engine, with just some adaptation needed on the lines. Those engines are getting cheap ($2k complete, sometimes less) with everything.

The down side is that the Chevy engine will be easier to make a lot of hp with. With the Audi V8, you will get maybe 350hp, and not much more no matter what you do. Both engines are reliable, but the Chevy would be cheaper to keep with parts available anywhere. I would say that the 40 valve V8 is probably one of the best engines Audi ever made, but if things do go south, you are looking at Porsche-like prices to fix it. The Audi engine will be a bit higher rev'ing and may match the stock Boxster gearing a bit better than the LSx. Hmmm, another interesting option.

[Topless]

Originally Posted by jaykay

How is the drivability and handling of the Boxster with the LS3 if I may ask.......I guess one feathers the throttle to get back to where it was originally as far as traction and balance....would you need a huge leep / amount of seat time to handle it? Have wheel widths been changed..square? I have been on track in a Cayman R (I think the engine was stock) and found that to have just an insane amount of momentum.....well it was the old Mosport, lots green and yellow traffic, R comps....anyway it felt way way over my head even in the power department.

I favor the big fat torque curve driveability of the LS3 over a 951 or 930 that hits you hard when the boost comes on and if you are not steering straight ahead, tosses you unceremoniously into the weeds. Like a GT3, Z06 or any high hp car, wisdom suggests we ramp up our speed gradually and avoid running around stabbing the throttle unless we like buying a lot of fresh rear tires.

[BoxsterLS376]

Greetings everyone,

Sorry for the delayed reply, been busier then normal at work tearing down a 1965 911 to send it off for major bodywork and rust repair. Plus my grandma had a stroke a few weeks ago so I've been spending more spare time at the hospital then I would like. She's doing better now but lost most use of her left side so things will never be the same

Ok sorry again for starting off on a downer! That being said I have not heard from Renegade yet and tomorrow marks 6 weeks since ordered, although i'm sure they will call as soon as it is ready, i'll reach out to them today. I still need to send off my power steering lines which I just pulled off this weekend so they can make the appropriate lines for the electric steering conversion too.

Also need to go ahead and get the motor coming which i'm going to try and order today. Hopefully they are still in stock and can probably have it by the end of the week.

Since the car had a coolant/oil failure I really need to clean out the cooling system too and make sure there is no guck in it. I have been thinking about it and may go ahead and upgrade the radiators since I have to pull all that crap out. Any of you tried the upgraded radiators from CSF?? I can get them for a little under $400 each and think it's a good "while you're in there" upgrade.

I also appreciate the PM's and emails I have recieved from a few of you and will try to get back to them all. Very excited to get started on this project!!

I'll definitely update again hopefully in a few days when things start to show up!!
Thanks!
J

EDIT: Just spoke with the folks at Renegade and looks like they are just waiting on a few small bits and the kit should ship out later this week or early next week!

[BoxsterLS376]

Haven't had time to go through it all yet, but most of the stuff from Renegade showed up today! w00T w00T!!

[Pdwight]

Somehow I expected a lot more stuff

[BoxsterLS376]

Well that is not quite everything, still waiting on the electric water pump stuff and steering lines, but otherwise that is most of it. Plus it is all still wrapped up in cellophane so a bit hard to see everything. I'll get some better pictures this weekend.

It all looks very nice, mounting pieces all powdercoated black. Although right now it looks like just a mess of parts, hopefully once the LS arrives it will all start to make more sense!

[Boxster 50]

How is the Ls conversion coming? I am very interested in how complicated the conversion will be. Does the kit require welding and or extra fabrication and do you think this would be over a weekend warriors head?

[BoxsterLS376]

Originally Posted by Boxster 50

How is the Ls conversion coming? I am very interested in how complicated the conversion will be. Does the kit require welding and or extra fabrication and do you think this would be over a weekend warriors head?

Greeting everyone,

The conversion is just about to kick off in full swing as Fedex is currently lurking around with my new LS3 crate motor which should be here today! I have also finally recieved the remaining bits from Renegade so i'll get some pictures up ths week. The car is currently torn down and ready to get started with the major surgery which should begin this week.

Boxster 50 - to answer your question simply, no, probably not, but that depends on the tools and skills you have more then anything. This is MAJOR surgery and definitely more then initially expected.

It is a lot more then just nibbleing away some of the firewall to make room for the valve covers, you have to cut out a section about 2 feet long that hollows out the frame then you have to weld in the "optional" side plates and reinforcement brace, which also serves as the new place to mount the emergency brake bits, which also have to be relocated.

***BREAKING NEWS*** MY MOTOR HAS JUST ARRIVED!!!!!!! Now to figure out how to get it out of the back of the truck! Can you believe there are 480 horses in that little box! BTW shipping weight on the LS3 is 556 pounds for those of you keeping score.

Sorry about that! Ok so to say the least there is a good bit of cutting/welding so it is not a project for the faint of heart.

I'll be back with more updates soon and some pictures of the progress once I start cutting its guts up this week. Although I must go ahead and say that I do wish Renegade offered a bit more guidance on the install process. The only actual instructions recieved came with the Kennedy engineering adapter plate. Otherwise I recieved about 40 pictures from Renegade and that is about it. Plus nothing was labled which for the most part it is somewhat self-explanatory, but would it really be that hard to come up with a few labels for this stuff?

Also if you are looking to purchase the kit, don't pay any attention to the "optional" listing section, NOTHING IS OPTIONAL. Ok I say nothing but if you want the car to retain normal creature comforts such as A/C and power steering, oh yeah and the alternator... then nothing else is optional so just go ahead and budget the $6800 for the whole shebang because while you "can use the stock clutch", it won't hold the power.

For those who have asked about the motor etc. I did a bit of shopping around and I ended up buying my motor from Scoggin Dickey Chevrolet in Lubbock, TX. Travis helped me out and was VERY knowledgable about the motor and the hot-rod aspect so I would recommend talking to them. I bought the LS376/480 with the optional GM Hot Cam, along with the ECU/harness/gas pedal assembly and total on it all was $7,836.79 including shipping.

Be back soon!
Thanks!
J

[JRL]

Great news John. I'm really anxious to see what all is involved and will give you a call soon to set up a time for a visit. I'm only about 10 miles from your shop.

I'm going to look at a car Friday and have started my search for the best price on a crate motor. I'm leaning towards the LS 525 which may be over kill but it's hard to imagine too much power :-)

[Topless]

Originally Posted by JRL

I'm leaning towards the LS 525 which may be over kill but it's hard to imagine too much power :-)

Just remember you still gotta get all that power to the ground through the clutch, trans, and axles that were engineered and designed for 250hp. Powerful cars are great. Powerful cars that always break... not so much. Choose wisely.

[Qmulus]

This is great! The engine sounds like a great deal for what you get.

I saw the Kennedy Engineering flywheel and adapter plate setup, and they look like very nice pieces. A local guy is building what he calls "street rails" using a tube chassis with various engines and Boxster transmissions. He just got an LS1 from a Corvette and a Boxster S six speed transmission to put in his latest "car". From what I can see, the LSx + adapter is significantly longer than the M96. I was a bit surprised to see how thick the adapter plate was to accommodate the starter. It looks like some clever engineering or notching of the bell housing could save an inch there. It will be interesting to see how that all bolts up.

I can't wait to see more!

[Pdwight]

I thought the S 6 speed was good to about 450hp

[JRL]

The Boxster S gearbox is plenty stout. This one is handling over 600 HP.

LS V8 Boxster Conversion From Renegade Hybrids! - YouTube

[JRL]

Originally Posted by Topless

Just remember you still gotta get all that power to the ground through the clutch, trans, and axles that were engineered and designed for 250hp. Powerful cars are great. Powerful cars that always break... not so much. Choose wisely.

The flywheel, clutch and pressure plate are replaced with stronger components.

Sorry but the Boxster S transmission was designed for far more than 250 HP. It is essentially the same box as the 996 series cars internally.

Renegade has a running car with over 600 HP and the transmission is fine.

And FWIW I know all about getting the power to the ground.

[Boxster 50]

Looking forward to the pics. I do have experience with fabrication and welding and have the tools. Plasma and welder. It does make me weak in the knees to think about cutting up a perfectly running and driving car.... I am hoping the kit comes with a template for alignment purposes. I would think alignment would be key to keep unnecessary bind off the axles and of course for fitment. This is the first I have heard of tampering with the e brake. Will it be unsightly ?

[Boxster 50]

Originally Posted by Topless View Post
Just remember you still gotta get all that power to the ground through the clutch, trans, and axles that were engineered and designed for 250hp. Powerful cars are great. Powerful cars that always break... not so much. Choose wisely.

When I spoke with Renegade they said the trans was holding the power from a LS7 but the axles were the weak link. He also said the car with the LS7 was a track car so you know it has been ran hard with many hours. He did say they have a fix coming for this by the way of after market axles.