supporting mods for 20g

[Logue]

wondering i'm will soon be getting a 7cm 20g. i have the safcII, 550's and 190 fuel pump. and greddy 24r.

you guys think those injectors are enough.

i'm at 20psi on b16g right know and there fine.

running maybe 18-20 on street
and 24-25 at the track

 

[Blue92]

I run a Hahn 20G @ 20psi with 550's and it is fine. I haven't tried to turn the boost up yet to experiment, as I just put my car back together. The only way to know for sure is to try it. Get a wideband if you don't already, they are cheap, only ~350. I got an LM-1 and love it. That is the only way you will know for sure if they are enough for you. Check out my mods list, I drive my car to work almost everyday. It runs great and pulls like a mother when I open it up. But, the first thing on your list, in my opinion, should be a wideband.

 

[Ed98GST]

First thoughts for 18-20psi on a daily driver on pump are that 550's aren't enough. But, like Blue mentioned you'll have to give it a shot to see. In addition to looking at your A/F with a wbo2, a good start would be checking injector duty cycle with your logger on the b16g. Would definitely help you to see where you're at currently (with the b16g).
I know you didn't ask about other fuel items, but you may also want to consider an afpr and bigger fuel pump. If you were set on staying with the 550's, that would at least give you the ability to dial in the fuel pressure and more fuel to play with.

 

[Blue92]

Ed, I run all day @ 20psi on 93 oct with 550's at 40psi base. I also have -06 lines and an adj fpr. I have noticed with the installation of the -06AN feed lines that my narrow O2's have gone down. This is why the wideband O2 is crucial, I have it on through my scanmaster and constantly monitor knock and O2. I have had no problems what-so-ever. From my experience, 550's are plenty. His 190 pump should be fine also. Do the math, 190 l/hr * (1/60 hr/min) * 1000 cc/min = 3167 cc/min divide by 4 injectors = 791.75 cc/min per injector. One can run 720cc injectors off a 190 lph pump when it flows 190 lph. Bottom line is, do the math. Math doesn't lie, calculate the equations out and you will save money in the end. Don't waste money on stuff you don't need.

You already have 550's, keep them.
You already have a big enough pump, keep it.
Judging from your profile you don't have a wideband, get it.
Go from there using log data, do the math to determine what you need.

 

[kpt4321]

You need bigger fuel injectors and a bigger fuel pump if you want to be able to take advantage of the turbo.

You can use 450's with a 20g if you want, but that doesn't mean it's safe, makes sense, or is a good idea.

 

[Ed98GST]

Bottom line is, do the math. Math doesn't lie, calculate the equations out and you will save money in the end. Don't waste money on stuff you don't need.

Speaking of math, what's your duty cycle and pulse width? Just curious...

The issue with tuning to the 550's "fullest potential" with a larger turbo setup is that you don't leave much room for hiccoughs, tuning errors, flukes, etc. The flip side of "wasting" money on things like bigger injectors and pump are that you could potentially end up spending money to fix things that were broken by maxing out injectors. Not trying to say you're wrong, just some food for thought.

 

[Logue]

thanks guys,

i am listening to everything your saying.

definitly i'm getting a innovative wideband

I will probly end up upgrading to 650 and a 255lph.

mid 13's was my goal starting out. i really didn't want to go faster. that stage is gone. i would like 12's

o yah how do i check my injector duty on obdII logger i didn't think i could?

JJ

 

[DsMWookie]

If all u want is 12's you can do that on a 14b......a small or large 16g can burry u deep into the 12s if not 11's. Might want to do supporting mods then 20g.

550cc are like 295$ new
650cc are like 310.....spend the extra cpl bucks and go for some big boys and just dial them in....wally pump is like 99$

 

[kpt4321]

Do the math, 190 l/hr * (1/60 hr/min) * 1000 cc/min = 3167 cc/min divide by 4 injectors = 791.75 cc/min per injector. One can run 720cc injectors off a 190 lph pump when it flows 190 lph. Bottom line is, do the math. Math doesn't lie, calculate the equations out and you will save money in the end. Don't waste money on stuff you don't need.

Things like this really make me mad.
No, the math doesn't lie, if you use the right numbers. If you use the wrong numbers, like you did... What you just said isn't correct, at all.

At 20 psi of boost and 40 psi of base fuel pressure, you have 60 psi of absolute fuel pressure being pushed by the pump. At 60 psi fuel pressure, the Walbro 190 flows about 33 gallons per hour, which is 125 liters per hour, NOT the 190 lph that you erroneously quoted.

At 125 liters per hour, you can support 520 cc/min of fuel flow. Interesting, that's not even as much as 4 550 cc/min injectors at 100% duty cycle. If you want to even max out 550's, then you better get a bigger pump.


Like I said before, you can run a 20g on 450's if you want. However, 450's and 550's are going to limit you to a power level you could make on a 16g, and if you're going to do that, why even bother buying the bigger turbo?

 

[kpt4321]

definitly i'm getting a innovative wideband

Good choice.

o yah how do i check my injector duty on obdII logger i didn't think i could?

You can't.:thumbdown

However, the wideband will show you when you run out of fuel.

 

[Logue]

thanks kpt,

u know your stuff. i didn't want to start wars just trying to see how far the 550's will go.

i understand they will get there but there not enough to bring out the full power of the turbo. Which i would like to do.

i know i could get 12's with my b16g. but it seems like i would really be killing it. The 20g would give me alot of power up top end which would be nice it seems that is where alot of the trans ams and crapstangs start to catch up. i would like to put an end to that.

 

[Blue92]

Well, I looked deeper and got "proper" numbers for 18psi w/40 psi base on a 190 pump at 14 volts via pump info
162.78 lph calculates to 678 cc/min injectors. I know my car makes 14 volts when I race. I also came across the FP website that said that pump will be good up to 400 whp.

Ed, I am at 17.41 ms injector pulse width, at its highest value in the pull. I have to check my duty cycle.

Logue, all I am trying to say is that I would get the wideband and do some pulls. Whatever boost your spring is at, should be around 15psi, use those numbers to determine the performance of your current setup. Since you already have an upgraded fuel system, see how it performs and determine upgrades from there. Its up to you, its your money. I put my .02 in, I don't want to turn this into a post about what certain components will and won't do.

 

[kpt4321]

i know i could get 12's with my b16g. but it seems like i would really be killing it. The 20g would give me alot of power up top end which would be nice it seems that is where alot of the trans ams and crapstangs start to catch up. i would like to put an end to that.

You can run 12's on a 14b, so that's not going to be very hard for a 16g. Pushing a 16g is 11's.

 

[kpt4321]

Well, I looked deeper and got "proper" numbers for 18psi w/40 psi base on a 190 pump at 14 volts via pump info
162.78 lph calculates to 678 cc/min injectors.

Now that is VERY interesting!

I got my flow numbers from here:

http://www.vfaq.com/mods/Walbro-specs.html

And they do not match the numbers on the RRE website! I wonder which of them is right?

I also came across the FP website that said that pump will be good up to 400 whp.

Keep in mind that you can make 10-20% more power on race gas than you can on pump, because you run quite a bit leaner.

I agree with you about testing, that's the best advice you can possibly give. While it is good to theorize about what the components are capable of, it is even better to check them yourself.

 

[Blue92]

I agree with you about testing, that's the best advice you can possibly give. While it is good to theorize about what the components are capable of, it is even better to check them yourself.

I am glad we can agree on something. I don't like arguing that much.

And they do not match the numbers on the RRE website! I wonder which of them is right?

Yeah, they aren't even close. I took readings at 14v from the RRE site. I personnally know a guy who has a syclone who runs a 190 with 63 lb/hr injectors without a problem. His truck has gone 10's. I guess that is just one instance of that pump flowing for 6 big injectors. He runs a FAST also, so he knows his shit is good, but he also runs 110.

 

[99MITSUGST]

wow...i dont know shit...i thought i did...i dont...this sucks

can i study under one of you guys? like the kung fu draggon or somthing?

 

[kxc36g]

In my experience, 550s with a 190L pump are enough for about 16lbs on a 20G; I dynoed about 300WHP with this setup on pump gas at base fuel pressure, but 02s were high (12s to even, gulp 13) I probably could have squeezed a little more out with better tuning and fixing some exhaust leaks, but fuel was limiting my control over knock.

I have since upgraded to a 255HP pump, aftermarket fuel filter/feed line and 650 injectors. I am happy to report that I run 20lbs on pump gas with 0 knock. This is at stock fuel pressure.

I like RCs website for injector flow numbers. RRE has good info on pump flow.

If you get 14volts to your pump, "while racing" please let me know what setup you have because I can't get that kind of voltage to my Optima Red top with a 2nd 8gauge wire running from the alt to the battery.

Chris

 

[sweet97]

I've been following this post and would like to ask a couple of quesions, LOGUE I apologize and thank you for barging in. If 550's are not enough for a big 16G but 660's are great for a 20G I am lacking both the knowlege (no arguement there ) or info. I have a 50 trim which I believe would flow 710CFM at 15 PSI. I ran an EVO with 550's 18PSI which was about max on those injectors. When I got injectors for the 50 trim I used a 30% increase in airflow so I got 30% larger inj's, 720's which are apparently too large. What CFM does a TD 06 cold side with an 06 hot wheel in a stock hot housing flow?
What injectors should a big 16G run to stay at an 80% duty cycle? It seems that 660's are the best for a big 16G, up to a 20G and including a 50 trim. Finally I bought a 255lph Walbro but never installed it because I can easily run lower than a 10:1 A/F on my wideband with the 550's with both the 16G and the 50 trim though at 13 PSI with that! please comments?
PS: the previous owner(s) left signs of having modded the car so the pump may not be stock. Mark

 

[kxc36g]

You don't know if you have an upgraded fuel pump?

 

[sweet97]

Nope, don't know what's in there. funny thing, it's the first thing I bought along with an MBC. With the wideband and scanmaster I can monitor. I can run i rich off the scale. Volune is there. When I go to an AFPR th pump goes in. Mark