So on Sept 30 you had "5. FVD Exhaust, 200 cell cats, FVD Headers, IPD Plenum and Custom Cobb Tune -- 524whp and 651ftlb tq"

After adding Y-pipe and IC you never really got the same torque numbers. Any idea why? Clearly the COBB provided more HP and TQ than FVD module. And clearly the Y-pipe and IC helped get more HP. But why did the TQ decrease?

 

At this point we have to back off on the torque John. But I am pretty sure his next run was going to be "the one" if it wasn't for that damn hose. Hopefully soon he'll get back on and verify. But it was headed in that direction before Eric let off.

 

Are we reaching the PDK's limits at those torque numbers? Or is it driveability? The torque numbers from that tune are clearly very very strong. The added intercooling allows you tuners to unleash the beast inside.

 

I have seen even stage 2's need to be tamed when custom tuned. Th IPD stuff makes them come on hard. We stay under 670-680 wheel.

 

looks like the nitrous car stopped at 700ft/lbs and no problem

 

As one who is considering the VTG upgrade when it debuts if we are reaching the PDK's limits with full bolt ons, what benefit will upgrading the VTGs offer without doing a full PDK build? Is the advantage more whee horsepower even if we cannot safely increase the wheel torque beyond 670-680? I suppose if we can get wheel hp way up over FBO numbers the car would definitely go faster especially on top which is the car's weak point with the OEM VTGs.

A PDK build is something I won't do -- just too much cash.

 

With higher flowing VTGs you can choose to do one of two things. One is to get more power at the same boost or two is to get the same power at less boost.

 

+1, turbos will be more efficient.


SDG, expensive is relevant

 

Relevant or relative? A PDK build is a lot of cash from what I have been told.

What is the performance advantage if the bigger turbos end up putting out the same power as an FBO car with OEM VTGs?

Seems to me, however, that the upgraded VTGs will add horsepower beyond what the FBO/stock turbo cars can do even if the torque has to be capped at levels the FBO cars can achieve (absent a PDK build).

 

Arggh relative. Typing from my phone and I guess it autocorrected


You really don't need a PDK build unless you are going nuts, but I was busting chops. If you want that much power out of the car you'd prob want to do rods and PDK, which is a whole other ballgame. Now using meth you will be fine doing upgraded VTGs and not running into PDK issues

 

I get it. No interest at all in water meth. I like my full sized frunk and don't want to run the risks that can arise from a failure of the water meth system.

Definitely do not want to spring for rods/PFK build.

I will stop at upgraded VTGs and am only interested in them if they confer a performance advantage over an FBO/stock turbo set up. If they can get us another 50-75 wheel hp that would work for me. That would get the car into the nines for sure.

 

The advantage is that when the turbos aren't working as hard the IATs stay down. If you look at some of the 1,000 hp mustangs they are only running 17-19 psi because the bigger turbos flow more total air mass but at a lower pressure. You also get a better margin of safety on your engine internals because they aren't as stressed. You don't have to run as rich, you don't have to pull as much timing, etc. The downside is slightly more spool time but with VTGs it will just be slight.

Of course, you can get all those benefits of bigger VTGs without tuning for the moon. Nothing says you HAVE to build a rocket. You could just tune at a lower boost and get much better safety margins at the same power level.

- Patrick

 

That is the Porsche ECU only if that is what you mean. I had Eric uninstall the Cobb tune that was on there so that we could see how the boltons did all by themselves. I was afraid that might not be clear. To me, that is damn impressive results for boltons and no tuning at all. Of course the custom tune brings out the torque and gets 10% more hp and the car is insane running that way. I drove it over to Cobb with the previous Custom tune on and those new boltons and it felt stronger but with this third map we put on, it's insane. I am going to have to be very careful exiting corners at COTA on Sunday but I am going to have at it on the back stretch to see what it can do. I plan to start my braking at 300 first and then back down from there. Don't want to overheat my PCCBs and ruin the rotors sooner than Karls went out but I do want to test this beast so I will be looking for a high speed run in that 3/4 mile back stretch.

 

Thanks. Great explanation. I want to stay within the limits of the OEM engine and PDK. Not going to do a full build.

 

COTA Cancelled, it flooded like hell out there this morning and the track said no way for Sunday. They are giving us a makeup date by Tuesday. Oh well............

If it's clear I am going out to my favorite county road on Sunday with the Vbox.