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16G Set-up Questions

Muskrat

Well-known member
Joined
Jun 13, 2004
Messages
2,107
Location
Lexington, KY
So I'm planning for my EvoIII 16G Setup, and have run into a couple of questions.

My original plan was to target about 350 bHp running about 20 psi boost pressure.

My planned Mods were:
Full 2.5" turbo back exhaust
MBC
ETS Intercooler kit
Rewired Walboro 190 fuel pump
650 injectors
EvoIII 16G turbo w/ 2g Manifold and O2 Housing
DSM Link and a wide-band to tune

I was running the numbers using estimates for Peak VE = .95 Intake Temp = 130*F, BSFC = .6 and assuming an AFR = 12.

With these numbers I reach my goal, with a Airflow of about 550 cfm and a Pressure Ratio of about 2.7.

The problem comes when sizing my injectors.

I keep reading about people running an EvoIII 16G with 550 injectors. This must be running stock, or maybe 15 psi boost levels?

I have a Walboro 190 fuel pump which I was planning to use. Based on flow data gathered by RRE The max injector size this can support with 20 psi boost is 660 cc/min.

Based on my injector calculations I should be running 690 injectors to be at 80% duty cycle, which my fuel pump can't support. Running 650's I'd be at about 85% duty cycle.

What my interpretation for all this is that I can achieve my goals with these parts, but I'd be just about maxing out my fuel system, leaving no room for error.

I guess my question is what are other people running with similar goals and set-up for their fuel systems? Should I be rethinking my set-up?
 

NARF

Well-known member
Joined
Jan 27, 2006
Messages
296
Location
Vernon ,CT
Bigger fuel pump.
walbro 310 will give you room to make those 650s bigger if need be..... plus you can go bigger than a 16g with it. The 255hp is tried and true as well
 

2of9

Well-known member
Joined
Aug 29, 2007
Messages
869
Location
IGH, MN
Currently, I'm running 550s, 190, and a 2g mas and the e316g, stock fpr(if it matters). Supposedly, I'm still running rich from the black smoke I see from doing some runs at about 18 psi. I'm not tuned though and I do not have a afr gauge to tell me where I'm at /ubbthreads/images/graemlins/banghead.gif /ubbthreads/images/graemlins/banghead.gif. For me, I'm still getting decent gas mileage 19ish city and 24 highway. just wondering if this information helps at all. With a dynotune, I'm guessing I should be at the 240-250awhp on a dyno jet and that is putting a smile on my face and is good enough for me to have fun in a car like this.
 

Rausch

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Joined
Dec 21, 2004
Messages
12,049
Location
Cleveland, OH
I ran 21-23psi on the Evo III with 550's. Injectors were essentially maxxed out though. 90+% duty cycle, which is more than the injector should see consistently... 660's should give you a bit more room than that, but ideally 750s would be better.


Target AFR should really be something safer though maybe low to mid 11's?
 

Polish

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Joined
Jan 10, 2005
Messages
8,936
Location
NE, IN
I'd step up to 3" Exhaust, just my .02. /ubbthreads/images/graemlins/cool.gif
 

NateCrisman

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Joined
Nov 22, 2008
Messages
2,054
Location
Blairstown, NJ
I would suggest you up the pump to a walbro 255hp or a toyota supra TT pump (higher quality than walbro). Also plan for an adjustable fuel pressure regulator, I go with Aeromotive brand and aeroquip -6 pushlock line/fittings to connect it to the rail.

Are you planning to run a MAF or speed density with DSMlink?
 

Muskrat

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Joined
Jun 13, 2004
Messages
2,107
Location
Lexington, KY
I was on the edge of running a FPR with the 190 but decided to see how it goes w/o before I commit.

I will either be running the stock MAS, or an EVO/3G MAS if I can find one.

Seems like most people suggest changing the fuel system. This is what I was thinking as well. Of course, if I upgrade the fuel system, I could throw together a completely different set-up/aim higher. Which is tempting.

The other option is to go ahead with my plans and just make sure I tune the car and adjust the boost to a safe level.
 

Polish

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Joined
Jan 10, 2005
Messages
8,936
Location
NE, IN
Quoting Muskrat:
^^Good god no. The thing is loud enough as it is, lol.



I've had 3" a Turboback with only a single muffler (no cat either) that was easily 2-3x quieter than two previous 2.5" systems I've used. Increased pipe sizing doesn't mean it will be loud. It's all about muffler choice, tip size, and exit point. I can however understand where you are coming from, I too don't like loud exhaust. Just wanted to mention though that with some luck and a proper muffler choice I bet a 3" system could be quieter than your current 2.5" while also freeing up quite a bit of power in the process, even on a lower Hp setup. /ubbthreads/images/graemlins/smile.gif
 
Last edited:

prove_it

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Joined
Jul 3, 2008
Messages
4,201
Location
Sioux Falls, SD
With the goals you have in mind I would no use a stock MAS. They tend to read poorly after 2k hertz. You will most likely exceed that threshold under full boost.
 

kartorium

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Joined
Jan 14, 2002
Messages
2,962
Location
ellensburg,wa
although it was long ago, I do remember at one point, I had 550's and a 16g. I replaced the 16 with an evo, went to 21psi, and needed injectors. I purchased and installed 680's IIRC and all was well. obviously more to it than that, but this is an influenced post.
 

chrisb33

Well-known member
Joined
May 3, 2007
Messages
363
Location
Manila, Philippines
Quoting Polish:
I'd step up to 3" Exhaust, just my .02. /ubbthreads/images/graemlins/cool.gif



+1 on the 3" exhaust. just get a quieter muffler if youre worried about the noise.

and get a walbro 255.
 
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CarRacer

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Joined
Jun 28, 2007
Messages
4,371
Location
Shakopee, MN
Anyone have an demonstrable proof of gain going to a 3" exhaust? I have a 2.5" turbo back system with a test pipe and a very similar setup to what Muskrat is planning.

I'd also shy away from the stock MAS. I run a 3G one for my setup.
 

CutlassJim

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Joined
Jul 17, 2006
Messages
1,694
Location
Manchester, NH
A single 2.5" exhaust pipe is good for around 50 lbs/min of airflow through an engine. 3" exhausts are just a DSM fad where ZOMG I need a 3" exhaust. Kind of like adjustable fuel pressure regulators. Let me get one and set it at stock fuel pressure, I'm so cool! That and my adjustable cam gears set at 0. Might as well put a shocker sticker on your car while your at it.


/rant
 

jb4

Well-known member
Joined
Sep 7, 2009
Messages
46
Location
Hampton Roads
I had a similar set up on a 1g. The 550's were maxed out quick above 22 psi. Ended up getting 1050's and an external wastegate. The external wastegate made the horrible boost creep dissappear. I would get a 255 hp and as big as you can afford injectors since you will be running Dsmlink.
 

turbowop

Well-known member
Joined
Apr 29, 2001
Messages
11,971
Location
Yakima, WA
Quoting CutlassJim:
A single 2.5" exhaust pipe is good for around 50 lbs/min of airflow through an engine. 3" exhausts are just a DSM fad where ZOMG I need a 3" exhaust. Kind of like adjustable fuel pressure regulators. Let me get one and set it at stock fuel pressure, I'm so cool! That and my adjustable cam gears set at 0. Might as well put a shocker sticker on your car while your at it.


/rant



AFPR's are a DSM fad? /ubbthreads/images/graemlins/uhh.gif
 

^Saying they are mandatory (which they aren't) and then never using them for their purpose is definitely something I see DSM people doing more than other folks.
 

Muskrat

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Joined
Jun 13, 2004
Messages
2,107
Location
Lexington, KY
Quoting CutlassJim:
A single 2.5" exhaust pipe is good for around 50 lbs/min of airflow through an engine. 3" exhausts are just a DSM fad where ZOMG I need a 3" exhaust. Kind of like adjustable fuel pressure regulators. Let me get one and set it at stock fuel pressure, I'm so cool! That and my adjustable cam gears set at 0. Might as well put a shocker sticker on your car while your at it.
/rant



Do you have a source for that number? I'm inclined to agree with you (aka 3" isn't necessary) just wonder where the number came from.

BTW: To get 350hp you're flowing about 40 lb/min. 400 hp = 46 lb/min according to my calculations. If CutlassJim's number is correct a 2.5" exhaust is more than sufficient for almost everyone on here. Granted a Cat, Glass packs, and mufflers will reduce this. The question is how much?

I think the AFPR "fad" is more because of overrun with a bigger fuel pump because the stock fpr's return orifice can't flow enough. I know it's possible to get around it, but IMO its easier to just buy a part that does the job properly.

I'm still on the fence about what to do. My rational side says just go with the 190 and 650's and tune for it. My problem is upgrading the fuel pump and injectors means adding a fpr. And also at that point I open myself up to other possibilities, higher power builds, which then bring more mods, and more $$ spent. I kinda want to get to a point where I'm happy with this car, and move onto the next project in a few years.

Also, 350 hp is basically the end of where you want to push a 16G. At about the 400 Hp mark you're running really close to the choke line. (all based on my calculations and assumptions of course). Which means even if I do go with a bigger fuel pump and injectors, I'll still be running at the limit of the turbo, which means if I do that, maybe I should run a larger turbo, which again, means more supporting mods and more $$ spent...

On the other hand, settling for the 190 and 650's probably means I wont be meeting me goal. By how much I'm not sure. Since I already have the pump, all I really need are the injectors. If at a later time I decide I want more I can always sell them and get some of my money back, and then buy everything I'd have to have bought anyway. I'll have to keep thinging about it. And decide what I really want.
 
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Polish

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Joined
Jan 10, 2005
Messages
8,936
Location
NE, IN
Quoting CutlassJim:
A single 2.5" exhaust pipe is good for around 50 lbs/min of airflow through an engine. 3" exhausts are just a DSM fad where ZOMG I need a 3" exhaust.

/rant



2.5 *will* flow enough to make that power, perhaps.

BUT 3" would make more. Guaranteed.

Someone in the Midwest had a Apex'i or similar type muffler (That necks down to 2.5" inside) on their car and were making around 450whp or so on the dyno. They cut *JUST* the muffler off on the dyno and the car picked up around 50whp. I forget who it was but the car was sold long ago and has been for sale a time or two since then. But to me that is more than enough proof. You can believe what you want.
 
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