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Thanks, both of you, I appreciate the honest pushback. I know a rear-engine layout isn't the "optimal" choice on paper, and I've looked at front-engine and mid-engine versions of this car. I chose rear-engine on purpose because I want the car to feel 911-like: lots of traction out of corners and under braking, with the character that comes with that. A mid-engine layout would also eat the 2+2's rear seats, which is part of why I bought a 2+2. To keep the weight bias under control, the plan is to mount the VR30 as low as possible on a dry sump, push it as far forward as the transaxle allows, and put the radiators, battery and fuel cell up front. I'm also expecting to need wider rear tires and a suspension setup that's tuned for it. If anyone has real corner-weight numbers from rear-engine swaps, or tips on suspension geometry for a tail-heavy car, I'd love to hear them. And if I'm missing a showstopper, please tell me now before I start cutting.

I am trying to get out one more time this year but the weather here in New England may say otherwise. Car has been good. a few minor tweaks here and there. I have about 650 street miles on it. Did get a tire puncture which is rough because the tire had 400 miles on it, I plugged it but I think I need to replace it if I'm going to race it because the internet says a plug wont hold with the heat of racing. I did get some photos sent to me from the event i did in September that i wanted to share.

I'll just add some things to consider. At the end of the day. if its what you really want and you have the facts and still follow thru then more power to you. A Porsche transaxle usually puts the axles 5-10" behind the bellhousing. so take that measurement into account and add any adapters needed to attach to the VR. Axles shouldn't really be more than 15º at the joints. so looking at the wheel centerline the trans outputs can be a max of ~3" forward the wheel centerline. Overall length of a VR is probably 30" (measure yours). My Z is about 32" from axle centerline to tail lights. So my math is showing the accessory drive/engine will be sticking out the back of the car by several inches to line the transmission up with the wheels with the MAX angle of the axles. Now to take that placement into consideration even if you build something around the back of the car to encapsulate the engine or extend the rear, the entire engine, accessories, bellhousing, flywheel, clutch, headers, exhaust, Turbos, intercoolers, etc will be BEHIND the rear axle. Google says a bar VR weighs 430 and almost 500 with turbos and intercoolers. so id estimate 600 behind the rear wheels that a normal Z doesn't have. Comparing to a front engine Z. The factory engine is mostly behind the front axle toward the center of the car. a 4 cyl or v6 would probably be completely behind the front axle. Porsche engine is probably 6-10 inches shorter than the VR. A well handing Porsche target 60% rear bias. stock z is around 50 to 52% on the nose Mid engine GT40 is 55-58% rear. C8 corvette is roughly 60% rear.

The show stopper is that it's a terrible idea. The Z simply is not meant to be rear-engined. It also sounds like you intend to keep a lot of the factory chassis (as opposed to a space frame and custom suspension) and make use of the rear seats. Well, you're going to have some 400-500 extra pounds way out in the rear of the car, and the factory suspension setup is not designed to cope with that, certainly not the relatively flimsy structure they're attached to. You're likely going to need a full roll cage to stiffen the chassis, at which point you lose the use of the seats. I think you'd be better off buying a 996/7 with a blown engine and engine swapping that. They've spent 50 years refining the chassis to suit the typically poor rear-engine layout, and it has excellent suspension on top of that, plus rear seats. You're basically trying to reinvent the wheel here. On the other hand, a VR30 in a Z would likely be just about a front-mid engine layout and would perform well if set up correctly. Those are your two realistic paths to a successful outcome, depending upon whether you prefer to have a Z or rear-engined 911. I strongly suggest you rethink your intended project here. It doesn't sound like you've thought through all the problems you're going to create by relocating the engine, and it is going to be very difficult to get it to work correctly. jhm also brings up a good point. What is your budget?

A front engine Z is pretty easy to get 50/50. An aluminum 4 cylinder swap Z is very easy to produce a rear heavy bias. Id expect the VR to also be ale to be rear bias. I can't see without adding a bunch of weight to the front, a real rear engine Z car would be like 70% or more on the rear which would not perform well in any discipline. Mid Engine has a fighting chance of being decent balance if you can engineer it to be.

Okay, don't do it. There are zero rear engined vehicles being produced today, other than the 911, which engineers at Porsche have stubbornly but successfully managed to develop into a good car. It would be one thing if you were wanting to do a mid engine swap, which the 2+2 chassis would give you more room for, but there is not a single reason I can think of why you would do this. You want the weight in the middle of the car, not at the very ends - research polar moment of inertia. I think you should stick to a front engine layout, as that is what the car was designed as. IMO, trying to turn a front engined car into a mid or rear-engined car makes no sense, and you're better off buying something rear-engined to begin with, and doing so it will likely produce a better result. Better to work with the factory design than against it. That said, if you want to reengineer the car, at least do something that makes sense, like a mid-engine. There's a good reason practically every modern super car is mid-engined and not rear-engined. You might provide some detail as to why you decided on a rear-engined swap to begin with, and what motivates you to take on such an extreme project. FYI, in the 20 years I've been on this site, I think I've come across exactly one mid-engine swap, which should tell you something about the nature of the project you want to take on. I think you might be better off building a car from scratch if you want a big fabrication and engineering project.

That's unfortunate. Glad to hear that the new shafts are better quality, though.

I had to buy them. If I had more time I would have gone an alternate route. Visibly they are heat treated differently and the spline cuts are cleaner. so I would suspect they had an issue with a supplier along the way and changed them. but I couldn't get any information from the guy on the phone. to put it nicely, the guy I dealt with was a "challenge" to deal with. took 5 phone calls and 4 emails to even get him to send an invoice.

not a great photo but i have an array of turn buckets hanging from the front tubular support I built. I do think it may get a little bit of a revision at some point as it comes off easy but its tricky to get back on.