16g air flow at 20psi?

[jbark]

so i came across this awesome post

http://www.dsmtuners.com/forums/tuning-engine-management/244522-injectors-fuel-pumps.html

and i was curious what the flow ratings on the evo 16g are at different boost levels. i want to see what size injectors would be best at 20-22 psi to keep idc's under 100%. i will have a rewired fuel pump and it can support

20psi = 43.32lbs/min
21psi = 41.55lbs/min
22psi = 40.67lbs/min

so i think im fine there. if any one has the flow of the turbo in lbs/min that would be sweet. thanks, jeremy

ps im tuning with safc and maft. so i can compensate bigger than 650cc's but i dont think i need that big.

 

[viperlp01]

according to this map of the big 16g which is very similar to the evo 3 at 20 psi about 1.4 bar your getting 400ish cfms

http://www.stealth316.com/images/td05-16glarge-raw.gif

every 10 lb/min is equal to 144.7178 cfm

so 27.64 lbs a minute... at 1.4 bar which is like 20.5 psi...

at 1.6 bar you flowing 30.4 lb/min but your starting to push the limits of effiecency and starting to blow some hot air...

BTW im tuning soley with a maf-t and im running 21 ish psi on 3 gallons of e85 for full tank with 680 PTEs and seeing some suprising lower idcs then expected... ###### gonna turn the boost up for the 4th and see if fireworks happen ..

 

[delta448]

...i was curious what the flow ratings on the evo 16g are at different boost levels. i want to see what size injectors would be best at 20-22 psi to keep idc's under 100%.

This all depends on your engine and the mods. Someone with a 4" bumper exit exhaust, 280 cams, port work, oversized valves, stroker bottom end and running speed density will see a shitload more lbs/min on the same turbo than someone who's car is completely stock except for an air intake and injectors.

i will have a rewired fuel pump and it can support

20psi = 43.32lbs/min
21psi = 41.55lbs/min
22psi = 40.67lbs/min

These are rewired Evo 8 pump values... I'll assume you know that and it's the pump you actually do have.

ps im tuning with safc and maft. so i can compensate bigger than 650cc's but i dont think i need that big.

Actually, the regular MAFT and SAFC compensate for the injectors the same way, so unless you have the MAFT Pro or whatever it's called, you can't really go much bigger than 650's when running straight gasoline fuel.

Both devices lower the airflow signal to lower the IPW for the larger flowing injectors. This affects the timing values that the engine tries to use and the timing advance is usually too much to compensate for anything more than 650's when on 93 octane and not run into lots of knock.

 

[viperlp01]

Im sure he will be fine with 650s running 25 psi or less tuning with those two devises on an engine that is not built like the heavens

 

[delta448]

I agree, he should be fine.

Datalogging is still necessary though, and that was what I was trying to incinuate when I mentioned the airflow differences in different engines and the part about knock.

 

[jbark]

It will be an evo 8 pump. And I am getting my cable soon in the mail to run evoscan. So running stock motor and 650s I won't push the idc too high. I have 550s now and wonder if I need to upgrade.

 

[jeffo]

I would run the 550's first, and see what your injector DC's are like. You will have to remove much less airflow with 550's than you would with 650's, so you will have less chance of having too much timing advance. I'm never in favor of removing 30% of the airflow signal with a MAFT or AFC, because of the extra timing, but fortunately the 2G maps are very conservative, and some extra advance on 93 octane is actually beneficial.
Have you checked to see if your ECU is an EPROM? Its much easier to tune the larger injectors with a chip. 650's are fine for 20-22psi, but I generally recommend 750's so you don't need to worry about upgrading again.
keydiver

 

[jbark]

actually to tell you the truth i never checked to see if its eprom. i will check. i guess that would give me the best tune .

 

[jbark]

well it is an eprom so how do these chips work. i have seen people use tham and is it hard. i guess you need to socket the ecu. but i cant not drive my car as it is my dd as well, jeremy

 

[delta448]

You should send jeffo a PM to discuss prices and such. Or you might just place your order on his website, DSMchips.com.

 

[->PrOjEcTGS<-]

You'll need to socket the ECU so that you can plug in a different chip. If you're good with a soldering iron then you can do it yourself. It will take about an hour to do. Or you can find an electronics repair shop and they can do it. I've done both. The first ECU I socketed I had a local TV/VCR shop socket it for $50. Gave it to them and came back in about 3 hours and it was done.

My current ECU I did myself. Get some desolder braid and a soldering iron. Some good quality solder and a socket and go at it. The hardest part is getting it desoldered and getting the old chip out undamaged.

Then once you have a socket you can plug the stock chip back in till you get either an aftermarket chip from DSMchips.com or buy a chip burner and some chips to play with and do it yourself. Download TunerPRO. Then get the 2g ECU Bin and XDF files off of the DSM-ECU Yahoo! Group. Load it up and start playing around with your tune. A logger and a wideband would be a great investment before any tuning is done.

650's will be fine for a 16g.

General Rule of thumb:
Small 16g - max of 36lb/min
Big 16g - max of 38lb/min
EVO 3 16g - max of 42lb/min (Some have seen 44lb/min!!!)