Newbie with some not so FAQs

[Brucelee]

I say go for it. I for one would love to be kept up to date on this.

Imagine an engine swap for the Box that doesn't cost $15G!

I have to admit that I like the fact that it will annoy the Porche intelligensia!

Imagine open the bonnet at a PCA meeting?


Hee hee!

[Finallygottaporsche]

post a pic of the mullet please

[chrisg]

Boostiality,
look what you started, you've opened up the 914club's box of motor swap debates !

Hell, unlike the teener, at least with the Box you don't have to mess with plumbing rads and you already have a tranny that can take some extra power.

[boostiality]

-986Jim

Hmm I think your looking at it the wrong way. I'm not trying to swap the t56 here along with the rear, its merely the motor alone. When we do it to the 914s, the only foreign thing that creates more length besides the motor is the adapter plate. which is only several inches. As for its orientation, the motor isnt horizontally mounted like the GSX, its just longitudinally mounted like say most of the worlds supercars. This is actually one of the big reasons why I like the chassis.

-Dr. Kill & BruceLee
I appreciate the support. I have alot of faith that it can be totally done under 10k actually. If you guys' want to check out some of the prices the Rx7/LS1 guys are paying for their swaps (also note we spend less b/c we're not going to buy and support the t56) check out www.hinsonsupercars.com. They even use the stock motor cradle, merely just modifying it with GM mounts and there you have it.

-Finallygottaporsche
Lol I dont have one now, but ironically I already did have the fau-hawk until recently

chrisg
Well great to see someone else with teener knowledge. And your right about the cooling part which just solves alot of headaches and would make the swap alot less complicated. If the 70s teener trannys can take basically 3x the amount of power and torque stock, I wonder what a late 90s boxster tranny can do

LS1 dimensions


Old SBC dimensions

[986Jim]

Okkk.. I wasn't sure how you were going to do the trans/rear end.

An adaptor plate with a custom clutch will work good. I made an adaptor plate for an Miata to run a full RX7 tranny rear end and drive shaft shop axels. We cut it from 1/2" aluminum and used threaded ARP bolts to each point.

THe clutch was a Miata flywheel and pressure plate with an RX7 spline in the miata disc. It was a pretty trick setup and held together well. The Miata made 476whp with a 50trim and spray, on 110octane. Pretty cool setup and the RX7 trans and rear end with a Kazz diff held up for 200+ passes down the track ~ 11.2-11.4.

My question would be then, I wonder how a 2.5L trans / axel setup would handle an LS1. The LS1 makes a lot of torque where the trans on the boxster is only technically designed for 200-220ft/lbs vs say 400. If you were to dump in a Quaife or Kazz it might work, then half shafts would become the next problem.

Another problem is the limited bellhousing size on the Boxster, again you will be stuck with a small sized clutch (whats the boxster? 225mm or so ish.. vs say 300? in an ls1?) which will take a lot of abuse from that motor.

[boostiality]

Originally Posted by 986Jim

Okkk.. I wasn't sure how you were going to do the trans/rear end.

An adaptor plate with a custom clutch will work good. I made an adaptor plate for an Miata to run a full RX7 tranny rear end and drive shaft shop axels. We cut it from 1/2" aluminum and used threaded ARP bolts to each point.

THe clutch was a Miata flywheel and pressure plate with an RX7 spline in the miata disc. It was a pretty trick setup and held together well. The Miata made 476whp with a 50trim and spray, on 110octane. Pretty cool setup and the RX7 trans and rear end with a Kazz diff held up for 200+ passes down the track ~ 11.2-11.4.

My question would be then, I wonder how a 2.5L trans / axel setup would handle an LS1. The LS1 makes a lot of torque where the trans on the boxster is only technically designed for 200-220ft/lbs vs say 400. If you were to dump in a Quaife or Kazz it might work, then half shafts would become the next problem.

Another problem is the limited bellhousing size on the Boxster, again you will be stuck with a small sized clutch (whats the boxster? 225mm or so ish.. vs say 300? in an ls1?) which will take a lot of abuse from that motor.

Daymn that miata must've been flyin'

The part about the tranny holding up is where its just going to be shot in the dark. I'm only going under the assumption that if porsche could engineer a tranny 3 decades ago that handled 3x the power/torque, we can atleast hope that the boxster tranny has the same strength behind it. Torque is what actually kills the 914 trannys and subsequently dsm trannys , hence forth why many owners use 283, 302, 327s etc instead of 350s. Wish I could have the funds to destroke the LS1 just so I could cheat around that torque issue or find other means of destroying low end torque without loosing too much hp in the process. I'll tell you something though, my 914s clutch was only 215mm lol. Again though I believe its all up to the driver. Many people have destroyed their 914s very quickly while others have the same tranny for years, its merely a matter of driving style.

[NNH]

Originally Posted by boostiality

Daymn that miata must've been flyin'

The part about the tranny holding up is where its just going to be shot in the dark. I'm only going under the assumption that if porsche could engineer a tranny 3 decades ago that handled 3x the power/torque, we can atleast hope that the boxster tranny has the same strength behind it. Torque is what actually kills the 914 trannys and subsequently dsm trannys , hence forth why many owners use 283, 302, 327s etc instead of 350s. Wish I could have the funds to destroke the LS1 just so I could cheat around that torque issue or find other means of destroying low end torque without loosing too much hp in the process. I'll tell you something though, my 914s clutch was only 215mm lol. Again though I believe its all up to the driver. Many people have destroyed their 914s very quickly while others have the same tranny for years, its merely a matter of driving style.

The gearbox should only be a problem in 1st gear because that's when the torque multiplication is trying its hardest to send the mainshaft ballistically out the side of the 'box. A few people in Britain have set lower boost limits in 1st gear when they've upgraded turbocharged cars, so you may be able to do something equivalent with either a modified EFI map or a simple adjustable thottle-stop operated by the gadget that does the stupid 1-4 forced shift on the LT1 Corvette.

As for the clutch, you can just run it till you kill it - it's not like there's any shortage of uprated Porsche clutch kits out there!

Good luck, it sounds like a very cool project. I'd love to see the whole car rock sideways when you blip the gas!

Simon

[BigBoxster]

[QUOTE=boostiality]"Can someone please tell me why you would put an American engine a PORSCHE?

Yes. Torque. An LS7 has twice the HP, but three times the torque. Also, Boxster is a great, balanced car and having more power is just mo better. It's really that simple. Everytime you jab the accelerator you get a thrill.

Putting a v8 in a Boxster isn't what Porsche is about.

That's a very nice opinion, but tell me why you have that opinion.

Porsche has used smaller engines and created amazing out put out of them,they are the whores of engines.

What are the whores of engines? Chevys?

Keep it in the family,put a 3.4 in there.

Well, I have one in my Boxster. And yeah, it's nice, but...

I had a TPC supercharger on it - and it had a very nice V8 like push to it. But I wanted more. I put in the 3.4 (oh, I might add that the very NIGHT BEFORE I did the swap, I burned a hole in a piston in the 2.5). The supercharged car felt faster because of the low end torque (like how an early '70 Porsche 911T felt faster than the 911S ) but when you stand on it and shift at the redline, well, it is faster.

But 427 aluminum block V8? Whoah Black Betty Bam-a-lam!

If you put in the American engine you would also as well lose the Porsche whine, there is no substitute.

You really need to make a good point here. Maybe something about weight. Becuase instead of a nice shredding whine (and my 3.4 with some aftermarket exhaust/headers sounds pretty great) - bu tthe V8 would give you a nice rumbling growl. I grew in the San Fernando Valley. I've always been into sports cards, but some of my buddies had hot rods with all manners of v8s.

"There is no substitute". Well there's another saying, there's no replacement for displacement.

See thats the thing, I dont posses this brand loyalty thing at all...

It really sounds like you do. I don't. I pays me money, I get what I want. I am no purist, but I am a pig for power.

"if joe dirt wants a LS1 or a 350 in his boxster, let him. who are you to tell him what he should park in front of his trailer home. .......i think i just used my first warning." I'll tell you this, when I get it done I'll drive around in a mullet just to show ppl that you can redneck anything including a porsche even if you are asian [/

Joe Dirt? Mullet? Like I'm unsophisticated because I like SBC in a Boxster? Buddy boy - I've got a cellar full of aging Bordeaux. You might prefer a grenace, or a chianti or something, but I like muscle. And finesse.

[cvhs18472]

I hope that you suceed in your adventure. It is because of people like you that allowed a High Performance 289 to be regularly put into an MGB. When the suspension was slightly tuned it was a monster. It was with great pleasure that I used to embarris just about anything that tried to play. Good Luck. The world needs people like you. Ed

[Mike_Yi]

Man, I would love to see you do this. My other car is an LS1 car, and that is one incredible engine. Though the Boxster sounds cool, it doesn't sound anywhere near as cool as an LS1 (even with the quiet exhaust I've got). The thing would be a beast!

Have you considered whether or not the chassis is strong enough to take all that torque?