utkinpol

as usual with such projects - if you have to ask - you cannot afford it.
it will be in same area as cup car engine rebuild or 3.9 sharky work.

imho if you are after such fun it is worth to buy your own lift and do most of work in your own garage. will probably save you $10-$15k this way.

Serge944

I would not call these builds "DIY" unless you have support from an experienced Porsche engine builder.

lopro

its too bad there isnt more info online on how to get your hands dirty with porsche gt3's

RSRanger

Interesting how Koro's power #'s seem rather conservative.
A thought come to mind, how do they get such larger displscements without having an issue with the oil pump?

Oh btw, thank you 911slow for posting the pics.

Ranger (Sua Sponte)

911SLOW

You are welcome.

I think that Koro is out of business.

BTW their numbers were not conservative. A better word is "realistic".

TTurbine

Whats the expected power output of your project?

And did Capricorn do any porting on the heads etc?

silverboy

I am using stock heads/cams. Put in new connecting rod bearings and ARP connecting rod bolts and GMG headers with high flow cats.

I would be happy with 400HP at the wheel or 485HP at the crank = +50WHP and 70HP (crank).

deputydog95

Don't the 997 3.6's normally make around 380 to the wheels? They always seem to make more hp than porsche advertises. I would expect much more out of it considering the expense.

Serge944

The 485 crank hp is a realistic figure that I think you will achieve. But that's not what you should be focusing on. The most pronounced change you'll feel will be in the low end/mid range!

Drivetrain losses are typically <10%, so figure more like 435-440 to the wheels.

TTurbine

Since your tearing your engine apart , why not just do it right with ported heads and cams?
I dont think the head porting or new modified cams will cost you as much as the engine assembley?

Serge944

GT3 heads are already a work of art - they are nothing like what is found in turbo Porsches. I don't think there's anything to port on a 997 gt3 head.

All cams have tradeoffs.

TTurbine

Thanks for clarfying i thought they were similar to turbo mezgers

silverboy

Serge is right. 7GT3 heads are a work of art but his 7GT3 Cup heads are truly desirable!

Anyway, my last Dynojet reading was 350WHP so I'll be using that as a reference point. It's useless IMO to compare HP ratings across various dyno's used.

Cheers,

silverboy

Just spoke to my Japanese engine builder who used to work for TRD Japan. He said the pistons I got from Capricorn are apparently made by Cosworth. He will also make sure they are blueprinted so there are no disparities in weight. :-)

lopro

amazing, sound like your on the right track. cant wait to see some pics and hear more. Good luck silverboy - this is going to be off the wall with goodness