MAPerformance: Ultimate R&D Thread | Air, Fuel, & Turbo Upgrades

[Herr_Poopschitz]

Adam, do you think the head is restricting even with the stock turbo? I'm wondering if we could approach that 400/400 mark on 93 with just ported heads, your tune and maybe a downpipe?

Not Adam, but I would say the benefits would be negligible. While not trying to get more boost to make more power and therefore superheating it, there may be some gains in the midrange, but you'll still be pushing the turbo out of its efficiency range w/ some rpm. On a compressor map what's been happening is moving the point upward, just making heat. Porting the head would simply move the point to the right, eventually choking the turbo.

This car was designed for everything to fall off a cliff at the same time...5500ish rpm it seems. A bigger turbo, imo, is a much more effective way to spend $. All of it needs to change to see GREAT gains.

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[Bomicino]

Why do you feel gains will only be in the midrange, and not every where else, as well as pushing power to the right? That's what cams will do, but with stock cams I'm not following the logic. Not trying to be argumentive, just trying to see what I may be missing. Doesn't VE show gains throughout the powerband? This is going to be an expensive car to properly make good power on.

 

[Herr_Poopschitz]

Why do you feel gains will only be in the midrange, and not every where else, as well as pushing power to the right? That's what cams will do, but with stock cams I'm not following the logic. Not trying to be argumentive, just trying to see what I may be missing. Doesn't VE show gains throughout the powerband? This is going to be an expensive car to properly make good power on.

Increased cylinder head flow 'will' increase power everywhere, but more efficient port designs rarely show drastic gains at low rpm (and the stock combo is torque limited due to rotating assy anyhow, not cyl head flow), and upper rpm will not be as dramatic an improvement due to stock compressor mass flow limitations, primarily. Ergo, fat midrange.

Anyone have a compressor map for the stock turdbo? I'll admit I am making assumptions (I'd like to think somewhat educated) about what I think it may look like.

 

[dragonacc]

I've seen it mentioned that our turbo is GT22 based several times. Here is the map for one of those that matches the trim and exducer that Adam listed as the stock measurements for our turbo -

 

[mtpavelka]

I don't know how to understand the compressor map :shrug:

 

[cosmo]

I don't know how to understand the compressor map :shrug:

The ovals in the map are the efficiency range of the turbo, so the best turbo efficiency range (76%) is the oval at around 1.75 pressure ratio and 15 lb/min. The pressure ratio is regarding the ratio of the pressure at the compressor outlet divided by the pressure at the compressor inlet (atmospheric at that sea level). The lb/min is a mass flow rate, but you typically use the volumetric flow you're using and then use air density to convert. Go too far to the left off the ovals and you surge the turbo, too far too the right and you choke the turbo.

 

[s550ecostang]

Replace the turbo and call it a day. I've been down this road on my VW's, Mazda MSP, Nissan and Subaru. The stock turbo is a small twin scroll great for a quick kick and low/mid range power and that's it. Its the same story here.

 

[Juben]

I don't know how to understand the compressor map :shrug:

Here's an excellent write-up on how to read compressor maps and some other info to take into consideration.

http://www.superstreetonline.com/how-to/engine/0304-turp-compressor-map/


Edit: It's worth noting that they seem to have their axis references flopped. The y-axis is the vertical axis representing pressure ratio while the x-axis is the horizontal axis representing airflow. Otherwise, everything else looks correct.

 

[LStillman]

I've seen it mentioned that our turbo is GT22 based several times. Here is the map for one of those that matches the trim and exducer that Adam listed as the stock measurements for our turbo -

The measurements might match but there is no way this is the compressor map for the stock turbo. From the factory stock form is operating out of the range for flow let alone modding it.

 

[dragonacc]

The measurements might match but there is no way this is the compressor map for the stock turbo. From the factory stock form is operating out of the range for flow let alone modding it.

Admittedly it was a quick and dirty search this morning.

Maybe when Adam checks in he'll have better info.

 

[LStillman]

Needing some custom software changes from Cobb before we can go any further with the bigger turbo as it is flowing some serious air.

I don't think we are going to get much further without putting our ported cylinder head on. The factory head is KILLING this car up top, no matter how big of a turbo you put on it the head is only going to allow so much air through the engine.

Just for a comparison on this cylinder head, a stock ford escort head from a 1994 GT flows 25% more CFM than the ecoboost mustang head. It's terrible!

Details please those of us using ATR and self tuning would benefit from knowing ahead of time where the road blocks are currently.

 

[MAPerformance]

Details please those of us using ATR and self tuning would benefit from knowing ahead of time where the road blocks are currently.

They won't be a concern with an update that is rolling out soon, so there is no need to discuss in my opinion. If you have ATR you will get a pop up when you open it with an update when it is released, as long as you are connected to the internet.

Regarding the factory turbo being out of efficiency range factory, it is closer to efficiency based on that compressor map but still "out". The A/R on the compressor map posted is a little low, I believe ours is closer to .68 if I remember correctly. The factory turbo's sweet spot is about 1.625bar, which is 76% on the compressor map posted on the previous page.

 

[MAPerformance]

We are looking to throw a rod today boys! 500whp or bust...

 

[Ron@cp-e]

We are looking to throw a rod today boys! 500whp or bust...

hurry up already!:lol:

waiting patiently!
:frusty:

 

[MAPerformance]

hurry up already!:lol:

waiting patiently!
:frusty:

Hey, there is a lot to take in when making this power haha. I like to cover all my bases when it comes to tuning, with Cobb's assistance we should be able to get some new numbers today.

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