I couldn't agree more. My brother and I both have the 3" catless race version from speedtech. The sound is intoxicating and sounds very exotic. There is a howl that starts between 3-3500 rpm that is like no other regardless of throttle position. We couldn't possibly be happier with both of our systems. Anyone that hears it comments on how exotic it sounds. Will try to get sound clips up one day.

 

It will be hard for anyone in North America to get you that result unless it is at a speed event or something.


There is no doubt that the 63s on e85 approach the performance of the 68s on e85 on a non-built engine. But on pump gas the 68s still offer a worthwhile upgrade over the 63s. I'm speaking from experience - started with stock, then stock plus tune, then 63s and now 68s. For day to day driving with bursts of speed, the butt dyno and the pbox show a worthwhile improvement. From a highway roll at 75mph the 68s pull away from the 63s easily. I logged all of the pbox results in my other thread.


The 68s need the larger air inlet pipes and larger than stock injectors to get the performance from them and the value proposition may be questionable. i.e. for a little more money you could get the a2873 plus the parts to make them work, or even the a3076. But the power doesn't start to build until 4-4.5k rpm with the a3076 and that made the 68s a better choice for me. The 68s vs a2873 is 47 vs 48lb per minute of air. The 68s let me avoid oil and coolant lines, boost controllers, etc... That may not matter to some but it mattered to me.


The 200-300kph times may suffer with vtgs but that is largely irrelevant in North America. If you are a drag racer or roll racer (at sanctioned events) then it may be worthwhile going alpha or bigger.


I see that you are in the UK. I can only assume you go to specific events to get to 300kph because the roads there are busy, there are traffic cams everywhere, and I don't imagine there are many opportunities to get close to 300kph. I doubt I will ever see 300kph so I won't be able to give you the results you want to see.


Before my dynotune I hit 6.9s 60-130 on pump gas. The car has a bit more power now and I suspect it has knocked a few ticks off that time. I will try to get results at some point...

 

Hi There,

My cars at VMAX today although I cannot be there. She'll be VBOX and data logged as we are trying a new map. I also have VTGS albeit GT2 hybrids with larger compressor wheels. They measure 66.5mm if measured the same way the 68mm. I also have stock engine and am running very similar times to you at every increment. 0-300kph I'm running 26.5 secs and I run 1.3 bar of boost. I'm intrigued to know if the monster build 68 mm VTGS on forged built engines can hold on to their 800 whp all the way to 300 kph and beyond. At the same event which is a pretty crappy track on an incline I've managed 325kph in 1.3 miles. A friend with exactly the same set up as mine but with a catless exhaust has managed 330kph over same distance at same event. Its not ones better than the other as for 1/2 mile and 1/4 miles events I'm sure the 68mm beat the other VTGS. I'm looking forward to see what the 68mm do over the longer distance.

As an aside the VMAX record is held by a pal who who runs 9e which is tuner in UK at 369 kph over 1.3 miles. They're shooting for 386kph today so can't wait to see if the manage it. Amazing that built turbos can blow the doors off 918, Buggati, P1 , La F etc!

 

nice! what is the compressor inducer size on your turbos? I believe it is 49mm on the Champion 68s. They make them with the GT2 hotsides too and I debated getting those but I had heard there is a little more lag. Since I'm more interested in daily driving with short bursts rather than vmax I decided to stick with the stock hotside.

 

Like many people I waited with baited breath for the Champion 68 results on the guy's GT2 with built engine. As you know, no results were ever posted and the guy apparently sold the car. I got tired of waiting for other people to post their results so I just bought a pair and posted whatever results I could personally get.

 

They're OEM GT2 turbos so I expect they're stock GT2 hotside - I do not believe you can go bigger. Yes mines a little laggy. In fact the lagginess is why we have tried different map. We're trying to wake the turbos up a bit quicker. Trade off is whether it can still hold on to the power later on in the run without everything getting hot and ECU pulling ignition timing.

 

At least you have slightly larger hotsides to compliment you larger 66.5mm wheel. You would have better results/efficiency especially up top then having a standard 997 hotside with a larger cold side wheel.


I was in the same situation with my 996 EPL BILLET k16's and to me was a killer street package. I had couple runs with a friend 711RWHP Mustang up to 280+kmh! But once in 5th gear I could feel (especially after a 2nd pull) power dropping and the ECU altered timing etc to keep the motor alive with all the heat from the small pee-shooters.


For a great affordable street set up, you can't beat a re-wheels VTG's, it was like my EPL BILLET K16 package (but with more power)...that is what you call killer power under the curve, killer spool and damn good out right power for the $$$$!!!

Can't wait to hear what your car does in the event!


BOGG: I most likely would be getting intercoolers soon and would love to go for a friendly PUMP gas pull to see real world differences. I am still good to go with my stock intercoolers, but I feel you would pull pretty good up top with you 997.2 intercoolers as I am guessing my car pulls timing from high IAT's(hence one of the big reasons I drop from 7.2 to 6.0 with E85).....either way we need to at least go for a cruise if anything! Seasons coming to an end lets get a little meet going.






Thanks


Bobby Ali


ba

 

I was wondering about the inducer size on the "cold" side of your turbos. I'm sure it's stock hotside, wouldn't make $$ sense to change that. For example, my Champion 68s have a cold side inducer size of 49mm. I believe that is the part of the compressor that determines flow capability.


No complaints with lag with mine. boost threshold is a couple hundred rpm later than the 63s iirc. Perfectly fine for the street/highway driving I do. Not enough opportunity here to really open it up on long pulls to justify more lag.

 

Yeah let's do it! I don't recall my iat numbers on the stock I/cs with those turbos. But the 68s have quite a bit more torque in the midrange. At the very top I think the difference narrows.

 

9e runs 217.xx on tip 997tt ( lower boost ) yesterday. Just read it FB

 

I was out last night and was thinking of calling you, but I didn't know how late you roll.


I had a good couple runs with my brothers friends 01 Gixer 1000, stretched, pipe and power commander , also one of my brothers friend wanted to run me with his 2015 Camaro ZL1....hey don't look down at me like I beat up little helpless children HE called me out!! Actually both of them were stand up guys!


I will be posting a thread with vids soon!

 

The inducers are stock GT2 which are 45mm from memory. Hotside as mentioned before slightly larger on GT2 turbos and this contributes to lagginess with the larger compressor wheel. Top end on these turbos are fantastic but we need to find a way of waking them up more quickly.

Apparently the new map was working well on my car but we ran into some mechanical issues with overboosting in 5th gear so never ran her over 150mph to be on the safe side. If we can fix whatever is causing the issue we might be onto something with this new map but we can't be sure until we have data logged and vboxed her above 150mph.

Here's a few vids of a 9e 28 against some pretty quick cars. The video against the Macca (if we had 2 miles the 9e 28 would have passed the Macca 650S) and 991 Turbo S with 650bhp show well that it takes a bit of time for the turbos to wake up but when they do these cars fly. If we can wake them up quicker for a stock engined VTG 997.1 we'll have a pretty sweet all round street car.

 

How is Toby 997 gt2 runs?

 

not sure if he was there yesterday but he's 12th in the all time fastest

http://www.vmax200.com/results/

The 9e 28 in the vid above ran 205mph over same distance i.e. 1.3 miles. Its decat so a bit quicker than mine but hopefully my new map will take care of that lol

 

Nice runs! I thought you would do better against the 650S. You are right about your top end pulling harder then your lower end.


Any plan of action to get some more low/mid performance?


All the runs were nice pulls and some pretty close!