660's or 720's.....Hmmmmm?

[92GSXBaltimore]

ok so, after i fix my afpr prob, i am buying either 660's or 720's but i dont know which ones. i know 660's can take you into the 10's on a stripped down car, but i dont want a stripped down car.
http://www.dsmtuners.com/forums/showthread.php?t=177021
basically, i dont want to be reaching the max duty cycle and i also dont want to be rough at idle.
does anyone know where that horsepower calculator is online, i cant find it

 

[andymoraitis]

If you're staying with the Big 16G, 720's would be overkill since the turbo will be well out of it's efficiency range before it needed injectors that large. If the Big 16G is a keeper, then go with 660's. Keep in mind that if you opt for the 720's, a better tuning device like DSMLink is recommended to trigger the injectors so that the motor will idle like stock and not run pig rich.

RC Engineering's HP Calculator can be found here:

http://www.rceng.com (go under technical and scroll down the page)

Hope that helps,

Andy

 

[92GSXBaltimore]

i plan on keeping the b16g no longer than summer time. thanks for the info man

 

[andymoraitis]

No problem. If you're going with a 50 Trim or something along those lines, go big with the injectors and then tune with DSMLink. It's a great package and you'll be able to run the car they way it was meant to be run.

Good luck!

Andy

 

[92GSXBaltimore]

i already have a SAFC2

 

[andymoraitis]

I'd sell the SAFC and go with DSMLink since the control is much better and it's not "lying" to the ECU regarding airflow maps. I think if you were to stick with the SAFC and were determined to do so, you should at least get an EPROM ECU and custom chip from DSMChips that would compensate for your injector size and require minimal tuning on the AFC, Just my two cents, but I don't think AFC's are the best option when it's the only tool used to correct for larger injectors.

Andy

 

[oldman]

i already have a SAFC2

680 is about the max range on the safc, it would be pretty hard to tune the 720s with just a safc.

 

[DSMTalonAWD51]

720's are fine for an safc

 

[oldman]

720's are fine for an safc

And this is based on your own experience?

 

[DSMTalonAWD51]

based on a few people I know using safc 720s and pocketlogger, no problems. I know for a fact dsmlink is a much better option but it can be done with an safc.

 

[DSMTalonAWD51]

based on a few people I know using safc 720s and pocketlogger, no problems. I know for a fact dsmlink is a much better option but it can be done with an safc. he's already got the safc anyway

 

[oldman]

based on a few people I know using safc 720s and pocketlogger, no problems. I know for a fact dsmlink is a much better option but it can be done with an safc. he's already got the safc anyway

Like I mentioned before, it can be done but very hard to tune. Just because you know some one who is doing it doesn't mean, 1. every one can do it. (every car is different) 2. that your friends car is tune perfectly. I know he has a safc already, that's why I suggested 680s instead of dsmlink.

 

[DSMTalonAWD51]

ah, i cant read. wasnt tryin to contradict you i just have seen that it can be done

 

[oldman]

ah, i cant read. wasnt tryin to contradict you i just have seen that it can be done

Healthy and respectfull discussions are always good.

 

[GPTourer]

I would go with the 720s if I knew I was going to be upgrading to a bigger turbo then a b16g. Just so you don't have to upgrade twice. I never tried 720s with a SAFC2, but my 660's were a pain without an AFPR. Maybe you can get by until you get something better to tune with, but you'll have to play around with the fuel pressure to get it to idel good, but I'm guessing you won't get max performance out of your turbo until you get something better then an SAFC2.


In short, I would do DSMlink and 720s first and the turbo later.

 

[92GSXBaltimore]

i am totally aware that the dsmlink is way better, but i am simply not shelling out the loot for it, especially since people have gone 10's with an safc. i might just get the 660's and raise the base pressure to around 45psi

 

[PSiedTSi]

People use way too big of injectors...there was a thread on a 3/s board that talked about the problems of buying way to big of injectors(ill look for it again) it explained that its not even worth it to get bigger injectors even if "your buying to upgrade later"...it kills your pump gas mileage...660s will be plenty for a 50trim...theres no reason to go with 720s here at all...


Tony

edit: heres the thread http://www.3si.org/forum/showthread.php?t=262353&page=1&pp=10 these numbers may not be the ones for 4G63s but you can find that out if you do a little math...keep reading through the thread too it can be explained more throughout

 

[ShapeGSX]

Frankly, the 3S guys are behind the times. I'd take everything in that thread with a grain of salt.

If you get DSMLink and larger injectors, your gas milage should stay the same. You just have to compensate for the larger injectors inside the ECU.

I wouldn't use a huge injector with an AFC. Sure, people do it, but chances are your timing advance will be so high that the only way to get rid of knock will be to run lower boost.

 

[andymoraitis]

I agree with ShapeGSX. Trying to tune big injectors on an AFC is like trying to hammer a nail with a tree stump. It's downright barbaric. Spend the money and do it right, or don't do it at all.

Just my two cents.

 

[boostedinaz]

at least get an EPROM ECU and custom chip from DSMChips that would compensate for your injector size and require minimal tuning on the AFC,
Andy

Good advice ^^^
If you are going to keep the AFC then get one of these chips. It will make tunning a ton easier. It wont be nearly as ideal as DSMlink, but it will work just fine and you wont get crazy timming. It is only an extra 100.00 or so and has alot fo good options that are very usable.

I also agree with the original poster about everyone having to get the nicest and most amazing thing when its not needed. There are a ton of 50 trim, DSMlink, and everyother crazy part on cars that run maybe low 13's. That is horrible. My car will only get a 20G, AFC, chip and of course fuel mods and I will easily get low 12's on pump.

 

[DSM90AWD]

ok so, after i fix my afpr prob, i am buying either 660's or 720's but i dont know which ones.

If you buy Denso660s, they flow 710cc/min at 43psi (check with FIC if you dont' believe me). Denso720s flow slightly more (720-750) so really not much difference btw the two.

FYI.. I'm running ~350WHP on pump with ND660s @21psi on my 50-trim and seeing 85% DC max (DSMChip stg3 of course ).

 

[Mackzero]

I can vouch for the Denso 660s flowing more than rated. Jeff did my chip and even with his injector compensation, I still needed to lean out the base a bit more. I just turned the base fuel pressure up from 36.6 to 45 and I have plenty of fuel now. I was hitting 107% IDC but now I am in the low 90s to high 80s. I am thinking about upgrading to the larger injectors, but don't want to go overkill....

 

[PSiedTSi]

I was hitting 107% IDC but now I am in the low 90s to high 80s. I am thinking about upgrading to the larger injectors, but don't want to go overkill....

107% IDC is impossible but your datalogger will read it higher than normal...and the 2nd part about overkill thats what i got for you...overkill is too common

 

[Mackzero]

Yes, I know that is impossible, the datalogger will say over 100% though as you stated. I know what you mean about it being very common. I will not upgrade until I hit around 95% or so.