Ran the Cervelli Technical Service built 4.0 Mezger through the gears on the dyno today. We are now in the tuning stage and the engine sounds and runs fantastic with very much a normally aspirated feel to it. Sam and the team of Mitch and John have been great throughout the ongoing tuning process. Thumbs up! I'm also very impressed with the Tial XONA XR980 turbochargers so far. They have immediate spool and simply rip up top. 4th gear pull yielded 678whp/718wtq on a medium boost 1.1bar 91 octane file. Target once all is fine tuned is 1.25 bar on 91 octane. and 1.4 on 100 octane. Three days of flogging and tuning it at the track later this week... Cheers!

Sounds amazing, and seems to rev with ease. Do you have tech specs on those turbos? I have a sneaking suspicion I'll outgrow my 68mm billet k16 turbos.

I mean.....does it get any better?
That pull through the final 3 with the downshifts at the end. Congrats. High watermark.

Have fun at the track!

wow! not it's time to enjoy all the hardwork! go get em!

Now THAT was cool!

what kind of rev/shift light are you using?

It's a Motec dash along with a Motec SLM shift module located above the dashboard at the base of the windshield in your line of sight..

678whp/718wtq with still an additional 4 pounds of boost (and a race gas tune) to go? Going to be a monster!

All I can say is wow...and I envy you taking that car to the track...have fun You have built an incredible car and you have also helped so many people on here, enjoy! It will be great to see some more of your track footage.

I don't Nathan but Tial can provide them. It's a 3073 framed turbo which has a 73mm compressor. I sort of wish I had gone with the 3076 which has a slightly larger 76mm compressor because were are having to reduce the torque output of these turbochargers down low. With the 3076 we wouldn't have had to limit torque down low as much and had the benefit of slightly greater output up top. Tial told me the difference between the 3073 ad 3076 is very minor but I may still swap over to the 3076s this fall and sell these. Based on my experience running these now and K16s hybrids on a 3.6 and 3.8 previously, I believe the 3073s would work wonderfully on a 3.6 or a 3.8 and simply blow K16 hybrids out of the water. Tial also makes a smaller 28 framed turbo (XR770) which has a smaller turbine which will spool harder but have greater back pressure. These have a ton of torque down low but begin to run out of steam up top similar to K16s. The XR770s are sort of K16hybrids on steroids and I have a friend that is running them one a stock block 3.6 and really likes them as he replaced his K16 hybrids with them.

I really like he way the power comes on with the XR980 turbochargers as its nice and progressive, like a very powerful GT3 engine. This will be much easier on the drivetrain all the way around. It remains to be seen how durable these turbos will be long term but running them at 1.2 or 1.3 bar where they are just loafing along instead of the 2 bar they are capable of should bode well long term as they are barely braking a sweat. The good thing is that Tial offers wonderful support and parts are easily available. And yes, I have a suspicion that you will outgrow the K16 hybrids on your Cervelli built 3.8 very quickly..

Damn John those are some great numbers! Sounds fantastic!!!

Interestingly, John's current engine sounds a lot like a 991 GT3 I was unsuccessfully chasing around a racetrack last weekend.

Incredible, and more to come on race gas... What an amazing build John, thanks for sharing!

I should not have watched that...

That is extremely impressive, if you're missing approx. 4lbs of boost, and if my math is correct, you should be 700+ WHP when your tuning is done, on 91? What's your target for 100 OCT?

Dam that is cool, bravo on the build - I have asked Sam to tidy up my maps as well and am hoping to have them installed in the next couple of weeks, it definitely instills confidence in the electronic platform.

Again, bravo!

Wow, nice work John and car sounds great! That's a crazy amount of power for the track and should kill some lap records.