lol. Good thing there are adult diapers.

As I approach the dark side of my 40s I think more of self preservation than thrills.

 

for me, gmg springs and sways and the tpc module transformed the car at high speed. And low speed

 

curious which Xona? I had considered the a28 vs the a30 series. From the old area under the curve thread it looked like the a28 had excellent boost response and area under the curve. Todd from Proto had suggested a28s for tip cars but a30s for stick. Worst case, if my xonas are too laggy for my needs I will swap to a28s. Anyone know offhand the lbs per min for the a2871 or a2873?

 

Bogg I think they only offer the 28s using a 71mm compressor not 73mm. The compressor flow would be the same as we spec the compressor and turbine flow independent. This turbine will not enjoy having a 71mm on it. It gets released in aftermarket but we would never couple this wheels in a OEM production setting because of penalty you will have on turbine efficiency (also thrust loads in standard bearings setups). You will see it in pumping work across the engine or backpressure ratio as it is referred to. The 71mm is better mates to a GT30 turbine wheel.

Again if I recall my old specs on xonas correctly, lol, I think they typically couple a 68mm to the 28s. So the HTZ version of your currently HTA in your champions

 

K24F has some data posted, you can see his results using the 73mm xona GT30 version. This is a 3.8L so take that into account however looks plenty responsive. If you are really concerned I would use the 71mm version. I have thought of those for myself but not much data around to know how much top end you are trading off.

There is another thread on here with looks of info on the older generation alphas on a stock engine with the 76mm. I would look at those results and how the boost comes on to see if that is acceptable for your needs.

 

Oh man BOGG!! Here I just convinced myself over the past 2 years to not upgrade to Alpha's and then this year I said my excuse is my daughter started university.......I am bursting at the seams to 991 or do Alpha's / build ......and now your going to push me over the edge!!


Next problem, how do I tell my daughter to drop private university and tell her it is for a worth while cause !


Can't wait to see how it will shape up!

 

Hey Bobby, I thought you were a bit younger than me and my 3 girls are under 10. But then again I am a slow learner lol.

your car on e85 is already redonculous and if you went to xonas with e85 I think you'd have to build your engine. 991 is awesome but I'm not ready to part with a 6 speed yet so it's not on the radar.

I'm just hoping to get on pumpgas what the vtgs do on e85 without sacrificing driveability. The 3071 was a good spooler and the 3076 was a highway pulling champ. I'm hoping that the 3073 is the best of both.

 

It’s a natural progression for some. I don’t think you’re going to sleep if you don’t do it! It’s not costing you much and I got your back I think it’s gonna be a good thing for you!

 

I really appreciate it.

 

How about pump and meth injection? I know for some it may seem risky but when done with fail safes it may be a solution. Look at the success the 997.2 have with it. Something to consider.

 

iirc, you run lower boost on pumpgas as you were interested in reliable top speed runs. I ran with 1.55bar on pump with decent datalogs and did consistent 3.0 to 3.1s 60-100. Wouldn't be the best tune for top speed runs though.

I had considered meth. Would be a relatively easy install since engine is coming down but I have zero experience with it and based on some of the potential downsides I just decided to pass on it.

 

@IMI A: You would be amazed how good and fast the stock ecu will adapt. Race fuel burns slower by nature and "needs" the extra timing to make the extra power at the correct crank angle, when you use racefuel timing with regular gasoline (assuming it doesn't knock first) max load pressure will happen at the wrong angle, the ecu detects that and corrects timing to make the load targets.

This is why you will not make power (even lose some) with higher octane fuels without tuning, higher the octane more this is true.

 

I just finished rereading K24s turbo build thread - he has turbos which are very similar if not identical to what I'm getting. Rather than asking questions in his thread I thought I'd keep the info in this thread because I suspect there are a few newbs like me looking for info on what's involved with upgrading from vtgs.

What I'm wondering is: if you optimize the ecu tune for a given boost level, say 1bar on the HKS ebc, do you have to get a different tune each time you increase the boost on the ebc? Or does the ecu adjust to the higher boost with the same optimized parameters?

I must confess that this stuff is quite intimidating to me. There was something reassuring about swapping files on vtgs. Just sit in the car, press a few buttons, sip on a coffee while the upgrade occurred and bob's your uncle. I'm not worried about the additional complexity just the possibility for error and the consequences.

I guess that's why it's important to get hooked up with a tuner that will keep on top of things. Sam is my man. I know Todd from Proto has hooked up many of the guys on this forum too.

 

Tuning with a stock ECU is a little different than standalones - the factory setup is calibrated extremely well by some of the best engineers in the world. With mass airflow sensors (MAF) it doesn't matter what the boost is, it's reading airflow and injecting the proper amount of fuel. Any relatively well setup MAF car doesn't really need much tuning to turn the boost up/down.

 

There a few ways we can do it Bogg and there’s no wrong or right really. We can get the turbochargers set at a nice boost level and then tune the rest and have different maps for you on the access port. Or sometimes a better way to do it is to just have two settings (or more depending on what you’re doing) that coincide with each other in the controller and the access port. I know it’s a lot to swallow but I will have the hardware really organized for you and work with the shop on the install part. After that I won’t be as intimidating because all we have to do is calibrate and you’ll see it lines up pretty nicely. When you step back and look at the whole thing it’s a little bit much. Tod’s line kit that I got you is really clean and simple and the controller is pretty capable but we won’t go to crazy. We won’t need to.