legacycentral bbs

checking to see if anyone is running 18g turbo with stock ss injectors.

still going to be running wastegate pressure (9psi or so). any issues with this setup?

i got 06 intercooler mod and walbro fuel pump installed.

thanks in advance

Are you running any kind of engine management? If not I would be running a wideband at the very least.

An 18G will flow more air at 9psi than a VF11 will at 12psi. Driving the car without knowing what your fuel situation looks like is a bad idea.

i think you could do it but run an mbc at like 5ish psi. your not really gaining any power without a tune though

RJ93SS wrote:i think you could do it but run an mbc at like 5ish psi. your not really gaining any power without a tune though

I didn't think it was possible to run under waste gate pressure?

Skruyd wrote:

RJ93SS wrote:i think you could do it but run an mbc at like 5ish psi. your not really gaining any power without a tune though

I didn't think it was possible to run under waste gate pressure?

You can't.

thanks. looks like an mbc with low boost for now.

my dad is running wastegate on his td05

is he running wastegate on a 18g?

RJ93SS wrote:my dad is running wastegate on his td05

so would running the 18g with 440 grey top injector work?

how many psi can i run on this setup?

i really wouldnt. when revtronix has there chip done then have at her. i would go sti 550's with the turbo and a tune. that will really boost your horsepower

I max out my MAF at 12psi on a VF-11 with a 3" TBE.

Once you max the MAF your injectors go to full 100% duty cycle. This is bad for them. This is bad for power generation.

Most guys running 440's are using some sort of RRFPR or even an airflow management system of some sort. The ECU can trim the 440's at idle and low power levels, but once your MAF maxes out, you're just dumping fuel.

Another question, why are you wanting to use an 18g to begin with? Admittably, I do not know your full setup, but you may very well be putting the cart before the horse here. In order to really utilize an 18g you need to be running a tuned setup and keeping the rev's high. The 18g is going to spool up slower than most other turbos that will max out the ability of the 440's anyways.

skid542 (lee) - you are absolutely right. looks like when i rebuilt the turbo, i didn't look into the consequences of going from a 16g to 18g.

what options do i have now with it installed?

thanks.

apex'i afc, JECS MAF and get it tuned for whatever boost. If you need bigger fuel injectors, you can use the legacy n/a fuel rails to fit larger and more common injectors. It's really not a bad mistake.

JECS MAF - early 90's n/a legacy 20 dollars junkyard
Apex'i afc - about 200 dollars
n/a fuel rails junkyard - 10-15 dollars maybe?
injectors might be a bit more but you can always find used injectors on nasioc if you need them.

I don't know your setup but if you don't have an intercooler get one and do the exhaust if you havent.

dumb question but what is special about the JECS maf from the early 90's legacy? does it not read fuel cut above 12psi?

94legacy2.2 wrote:dumb question but what is special about the JECS maf from the early 90's legacy? does it not read fuel cut above 12psi?

I think it was tunable for more pressure "boost" than the stock MAF which I think Nico or somebody else on the forum posted that the stock one can be tuned for more if you take the back plate off. If I find the link I'll put it in this post.

http://bbs.legacycentral.org/viewtopic.php?t=26571


The MAF doesn't read the fuel cut. The MAP does

It doesn't max out as quick so if you have something to tune with, you can run more boost without throwing the injectors wide open.