Maybe just do the stroker crank part and not the bore? I haven't looked into what that would bump the displacement too. It might be close to a drop-in... The question would be if you could use your current pistons without any issues.

 

Correct, you beat me to it. Yes the Akra cats are larger and 300 Cel. Currently its not too loud in any mode. I can go the cans with confidence.

 

Thanks, I posted this thread so someone like you, would chime in. I haven't investigated it yet. I want to get the MoTeC fully operational on stock turbo's first. Then decide if I just do a pair of G25-550's on stock motor, or go all out and increase displacement for some larger G30-770's.

 

For your viewing pleasure

 

Keep us updated! I built a 600hp Volvo S60R 15 years ago and loved the hell out of it - even though it was a complete waste of 100K in mods haha.

 

If you are prepared for the possibility of blowing your motor or being in and out of the shop tuning non stop til it gets right then go for it. Just be ok with this when you start, just like you have to accept you may wreck your car on the track you may wreck your engine in the shop. Same thing really I suppose. It could be a long road to get back to a usable car and cost a lot. If you cant handle either of those things then I would not do it. If you can deal with that possibility thats cool and cant wait to see how fast it is!

 

with pockets deep enough for the parts he already has.... no big deal.

 

does it still have that heavy glass sun roof?

 

I’m curious; you are such a track rat, would that power even be usable? I get the “I want to build it if I can” mentality but not sure how you’ll keep that car planted on earth even if you put a big fat wing on there.

 

He's doing drag racing and not just road racing. Drag racing Is where the big power is used.

 

Oh I get that but I just can’t imagine all that power is usable on a track, which it appears he also does quite frequently.

 

I agree and personally would have gone RS or Turbo S - either for less money and simply upgraded the brakes (or started with PCCB) and suspension. That's clearly the more sane fiscal choice.

BUT.... I also can't talk too much as I have way too much $$$ poured into my 991 and 987 vs what I could have just bought. Not at the OP's level but I totally understand the journey of this and can relate to having a one off thing that is truly unique and a sleeping monster performance wise.

 

I did some quick research and the stroke would only increase to 81.5mm from 76.4mm giving almost exactly 200cc more displacement. And you'd most certainly need new custom pistons with the wrist pin location moved higher. So a ton of work for relatively little displacement gain (6-7%) and the extra stroke length would reduce maximum engine rpm though the valvetrain may still be the limiting factor.

 

Funny, but also true.

unfortunately yes. The car was ready to go. You may have noticed I am a little impatient.
But I never paid for the roof. You should have seen the look on the sales guys face when I said, “I’m not paying $6k for that! It raises the centre of gravity. It’s the stupidest thing I could think of to put in a Porsche. “. I never had to pay for it.

As for track performance. You can store 12 maps on MoTeC. You just toggle between them, rather than have to keep loading and flashing like COBB. So a refined track map that gives stock like down low power but dramatically increases top end.

I’m fine with endless tuning. My Son-in-law tunes the car. He loves it and is also a track rat.

A 720S has insane top end. I can stick with it most of the way around a track. It just ever so slowly pulls on my down the longer straights.

I would like to reverse that, where I am pulling on it down the long straights.

last track day, I handed two GT2-RS there ***. But the third one came out in the last session and set a cracker of a lap and just beat me. (That guy just got back from training at the ring. It definitely showed lol. He grew a pair whilst there.)

 

Being pedantic you have 1 map on an M1, but you have user input to allow on the fly adjustment via an additional axis on relevant tables.

The 12 number comes from there being 12 positions on most rotary pots but you can go higher (though CPU starts to become an issue with massive tables).

Good luck if you decide to go for it, for track use swap out the OEM ABS system too for Bosch M5 motorsport ABS, with an after market ECU you’ll have that option