to speak to your original question, i think u will find that a .2l bump is all u want to do in a non-metz motor. Engine builders that have been doing this for years struggle to get 40-50 hp more out if a base motor. Some of this is done by using x51 build logic so im not even sure those gains r available in your motor.

i say if u have the funds go for it. Remember that the brighter the candle burns the shorter it lasts.

 

Actually it's rated at 345 engine HP. At least that's what the book says.
Most people on this forum would be happy with a reliable 345HP, it seems.

 

so you would say just going to a 3.8L would be better than doing a 4.0L and then whatever that gets me just leave it as it is? just looking to make it a better street car with more life in it, but i also want it to last so that bit was helpful @De Jeeper 3.8L and take whatever i can get from that.

would anyone say i'm better off just buying another car at a certain point with how much money i would be putting into it, i.e. a turbo or gt3, something along those lines that come with more powerful motors to begin with?

 

You might try stuffing a Chevy smallblock in there if you want 600HP. I wouldn’t want a 996 engine to have anything close to that. Even the 996tt guys aren’t pushing too much beyond 480 without serious mods. But then 600+ is possible if you with that engine combination.

 

The Flat 6 Innovations boys can up it 4.0 liters and suggest, with their supporting mods, that's worth 100 hp +/- over stock. That is probably the closest you will come to a reliable "500" HP M96.

It's simple to get 480 HP from a 3.6 Mezger powered Turbo. 550 is not unreasonable. From there, bring truckloads of money and you can have anything you want, 1200 hp is doable.

Have you driven the car with it's 345 HP? I'm pretty sure it is fast as-is.

 

just joined today, looking at doing the same thing on mine but was debating between 3.8 and 4.0, moral of the story is if you want to do engine work on a 3.6 x51 go with a 3.8L over a 4.0L for reliability and longevity? and what numbers should i expect to be making from that?

 

oh yeah it is pretty quick as is, was just looking for something different than just turboing or supercharging it because i wanted to keep it n/a

 

A bump to 3.8 or 3.9 from a 3.6 generally requires no additional head work or flashing, however, if you up displacement you can take more advantage of tune and exhaust mods. A well-executed 4.0+ will use ported heads, bigger TB and exhaust exit, mapping and internal upgrades to push the curve where you want it. Bazillions of posts/threads going back over a decade on this subject. Enjoy the research!

 

how about the R-Series from F6 innovations? heard anything good with that you've heard

 

was about to say what the best option from F6 i know @theprf said something about that earlier

 

Perhaps my grammar let me down there. I mean porsche and every other manufacturer rate their horsepower at the crank, not the wheels. I was not referring to the number but rather the units

 

If your 996 C4S is a “forever” car...sure! If not, sell it and buy a 997 turbo for the same money.

 

Over the past 7 years I’ve probably watched 30-40 m96 race-prepped engines go across the dyno (my racing club, POC, is power/weight so we’re always interested in other competitors numbers ). X51 m96’s pop 315-325 consistently. No, your motor is not making 400bhp. It’s probably around 310 w the GT3 throttle body.

Vision has built a ton of 4.0 m96/97 engines. They put down 385bhp.

 

 

we're all just beating a dead horse at this point lol, but F6I seems to be the best way to go to make solid power, nice touch they make the case red too