werk96

You Tube v cool seeing ongoing developments for the 996 platform can't wait to see details on this 4.3L engine!

Great start but need more details especially pricing

I believe you can find a review of this car (or at least a similar car from Werk96) on YouTube already. Looks great, and the reviewer was quite impressed. You know how this works with pricing, though. Found it: You Tube

New video from the guys at Werk96…… You Tube Very cool insight into the 4.3L 450hp and 8k rpm motor they cooked up. TLDR is that it successfully is using steel liners with pistons that have DLC coating and some deliberate choices for rings. Not the most common approach we see in the states but looks very well executed with lots of testing and research behind it. Other notables are a roller bearing for ims, compression control through some head work and probably the coolest part of all is the sneak peak of an ITB setup for the M96 motor. Super excited for that. They’re also using the alloy 997 intake manifold which has tested very.

Yeah, I am following their work. Love the whole concept of taking on the 996, from interior to chassi and engine. I live in Sweden so this is actually a viable solution for me should my 3.6 blow up 😅 What I don�t understand is how they manage the oil starvation issue. Saw a FVD deep sump in the engine video. Any ideas?

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As a 996 enthusiast, its just cool to see what these guys are doing in its entirety. To your point, its one thing to rebuild and upgrade the engine components to make it better, faster and stronger for the street. But with any upgraded engine, you still have to solve for oil starvation and AOS failures. I suspect with their attention to detail and the track testing they mentioned, that they have thought about it. We pretty much know the solutions, but there is always something better that hasn't been discovered yet that we all can learn from. I sent them a message asking them the question.

4.3 is pretty darn impressive!

Very cool! I like the detail discussion. It's really hard to show people you are really the top guy without giving away all your secrets. But they've done a really good job of it. Also, they need to discuss the oiling issues. I have to believe these will end up on a track. They did say they've done track work. And given the apparent level of detailed thinking, they must've managed it. I expect it's a trade secret.

Bigger displacement doesn’t make it better but I appreciate and applaud their work on an old Porsche

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It sounds like it is bore/stroke increased. Do we know how Slakker/Hartech/LN/FSI increase their displacement? is it all stroke or a combo

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Quoted for posterity. 🗿

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Our 3.9L and 4.1L builds are based on a 102.7mm bore, using the 3.4L crank (for 3.9L) or the 3.6L crank (for 4.1L). We�ve also done a handful of 4.2L projects using an offset crank grind, yielding an 85mm stroke. Next year, we�ll be building three 4.5L engines using a 90mm billet 4330V-mod crankshaft that�s 30% stronger than the stock crank, along with custom rods and pistons. This combination keeps our rod-to-stroke ratio at 1.61:1 and our compression ratio at 12.5:1. Ballpark cost of $45k for the engine (including custom valves, springs, cams and porting) with a $10k refundable deposit to secure a slot.

4.5L is beefy and should be putting down some impressive torque numbers! I remember watching an old video on DeMan Motorsports and the work they did on the GT4. As they pushed the limits of the displacement, at one point they ended up getting close to the limits of physical dimensions of how big of a bore they could have. Any such concerns here with the 4.5L and will you still work with Hartech on this and Capricorn, who is providing the liners and pistons? Look forward to seeing that dyno session for sure! In that above video, they look to be using the 997 S aluminium intake manifold. I think that was mentioned as a potential bottleneck as you go up in power. I was most excited around the development of the ITB set up and it's something that Porsche has used in their Speedster and GT Cup cars so wondering if that's a potential solution to the problem.

Slakker what are the possible HP numbers on a 4.5 and at what rpm range do you think you’ll get to thanks

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I do have a design for a 4.6L using 104mm bores, but I couldn�t justify the additional machining and case modifications required for only another 0.1L. So the 4.5L uses the same 102.7mm bore as our 4.1L. This build will use a Hartech designed Capricorn sleeve, custom CP pistons, and Pauter rods. Our target is ~450 hp (I�m hopeful we can squeeze out a bit more) with an 8,000 rpm redline. On the intake: the 997S manifold (it�s actually plastic, just painted silver) makes good power, but it�s tuned for peak power around 6,600 rpm. We�ve also started modifying the 996 manifolds to achieve similar peak power, which has been working well. But if we want to take advantage of the higher RPM range and push power further, we need to shorten and reshape the runners � more like the 991 GT3 RS 4.0. That engine makes roughly the same torque as our 4.1L builds, but reaches 500 hp by carrying airflow to 8,400 rpm. As for ITBs � I think the video is solid overall, but I�m skeptical of the horsepower claims being thrown around. ITBs sound great and can improve throttle response, but they also largely negate the VarioRam effect, which is the key to the flat torque curve and wide powerband that makes these engines feel so good. Also worth noting: the 500 hp GT3 uses the same 82mm throttle body, which is rated around 920 CFM � enough airflow capacity to support roughly 700 hp � so the single throttle body itself isn�t a limiting factor.

Thanks for the explanation @SlakkerRacingDev ! At some point you need to check if the juice is worth the squeeze, especially when it comes to compromising durability of the motor. Good call on the manifold being plastic - could have fooled me as it looks like pretty smooth casting in photos! Look forward to seeing what you do with the intake management. Since the air path from the intake box to the head is fairly short, I was curious if intake temps play any role in it and if applying some heat shielding material (like the gold wrap stuff) makes any meaningful difference. I doubt it. I know it's a bigger topic on turbo cars that generate more heat. Another good call out on the ITBs and the VarioRam. It might be a situation of having your cake and eating it too. You can have a better throttle response and sound / driving experience OR a flatter torque / better power but not both. At least yet. Might depend on what you want out of the engine. I also hope that they post some dyno numbers and then again with the ITBs to show the differences. I'm sure getting all of it to play nicely together with throttle by wire will require some serious tuning time.

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Brandon, interesting info. Is this a modification you are doing in combination with head work and the inclusion of the GT3 TB and Plenum? Are you using the factory manifold or are you using an aftermarket manifold with equal length tubes?

Apparently they're using steel sleeves for these builds. I'm curious to see how their builds hold up over time/handle the different heat expansion issue with that recipe.

VarioRam on the 996? I know we have the resonator flap that opens just above 3k rpm. The 993 had the VarioRam, which is a set of tubes in the intake that would move to increase the intake runner length below 5k rpm. Maybe the name VarioRam went away with the VarioCam in the 996. Maybe I'm stuck in semantics. I expect the ITB setup doesn't care about lower RPM torque as those engine will always be running at high revs. Not street monsters like we want.

Its interesting that the builders (FSI, Slakker/Hartech, Werks) are now pushing 450 on a 3.6 rebuild. The questions I would have would be 1. Which build would provide engine durability on the track? 4.1, 4.3, 4.5? Where will the failures come from? 2. Which build would provide more power usability on the track?

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Just a guy speculating here...but it shows that the M96 isn't total junk when in the right hands and can be plenty stout when the weak points are addressed. I have no reason not to believe the claims but the builder from Germany claimed there are some engines running around with 200k km and lots of track time. Track access is a lot more affordable and accessible in Europe so plenty of folks can take advantage. Heck, Nordschleife is basically a toll road! As far as displacement vs durability goes, with more power comes more responsibility. I feel that as long as the known weak points are addressed, there is proper oiling and cooling , there shouldn't be a reason why an engine with a larger displacement can't go the distance. As they are mechanical objects, they will wear no matter what. So it will depend on application and a proper maintenance schedule to make the motor durable. I think you have demonstrated that with your car pretty well. Even then, a hose can burst, a belt brake or a diaphragm in the AOS can fail causing a failure but at least we know pretty well what should be done to prevent it. As far as track usability goes, I'm a noob at this but I would guess it depends on the track. When I met up with a local rennlister, we drove our cars back to back. He does track his 996 GT3 and said that my car would walk on his stock GT3 on a straight - you can't really hide the torque of the 4.1L so I'd only expect more from a 4.3 or 4.5L. Watching some of the dyno sessions from Brandon it's been very interesting to see what they can accomplish as far as the powerband goes by pulling various levers while tuning. There's definitely the aspect of being able to stay in the powerband when shifting so having the down low torque helps. I also think there's something to be said for mechanical sympathy of not hitting the redline at every chance. I'm sure the engine can take it but might decrease the durability long term, potentially.