now ok... new question
if i manage to be able to control all my fuel... would i be able to boost more then 5 lbs on my SE engine? cuz i know that was my main enemy was leaning out and popping a apex seal... but since i can do anything with fuel now... would i be able to boost more?

Cory

 

I dont know exact numbers, but I wouldnt boost it very high.

 

umm would anyone might know

 

you might wanna try the 2gen forum also

 

for what i can boost at with a GSL SE engine... i dont think they would know... its a first gen right so how would they know

 

hey just a idea dont get all pissy

not like your getting alot of help here

 

Its a 13B, they have 13B'S!

 

sorry dude... didnt mean that in a mean way at all... sorry if you took it that way... my bad...

yes i know its a 13b but its a diff 13b... arent the S4 engines and gsl se's diff... like compression ratios?

 

i dont think there is a big differance between the s3 and s4. theres a few ppl in the 1st gen section that are boosting. try looking up directfreak i know hes running 12 psi on low boost and im not sure on high boost but its dynoed at 385 at the wheels(IIRC)

 

its ok. I have been readin this forum lately like 24/7 and it seems that everyone says for boost questions to ask 2nd gen forums.

 

The question can't really be answered, without posting your mods. You might get a better idea of what you can do by searching the 2nd gen section, for the guys that have boosted thier na's. I don't remember the cr's off the top of my head, but the na's cr's are similiar between the S3 and S4's.

Fuel and tuning is much more critical on the higher cr's. If you are still running the stock injectors and ecu, 5 psi should keep you safe. If you want more, you will probably need to do much more than just bigger injectors.

The manner in which you asked the question leads me to believe you need to do a lot more research for the next level you wish to pursue. My congratulations to you for getting a turboed SE up and running.

 

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/boostin-se-436166/

see here for what the 2nd gen guys have said... and for mods i have done...ect..

 

Much better.

Stock S4 and 5 turbos, with mods, especially exhaust and intake, boost creep, badly. The stock ecu has a fuel cut built into it to prevent this. Dumbest idea Mazda ever came up with. They should have done ignition cut and put up excessive emissions instead.

You will need:

To port your wastegate.
Bigger fuel pump. Walbro 255 external.
A good boost controller. EBC if you can afford it.
550 cc primary injectors, low impedence, pre 87.5. If you have your oem SE injectors, use them for the secondaries and control them with the Megasuirt. Tune with a wideband.
I believe you will also need to do something with the fuel pressure regulator, but I am not sure on that.

Now go forth and search and learn. Happy boosting.

 

why would i need to port my wastegate? i'm only going to be boosting 5 lbs right now... i have a manual boost control for now... but i dont need it just yet i dont think... arent SE injectors high imp? how would that work... like running 2 high imp and 2 low imp? or would i have to convert one set to high or vise versa... how much would that fuel pump cost? and i dont think i'll have boost creep with my set up will i?

 

You asked about boosting above 5 psi, I gave you some of the basics to be able to do that. All pre 87.5 fuel injectors are low impedence.

Now, go search and learn the basics.

 

What ECU are you running?

 

I'm getting ready to boost my GSL-SE soon. I'll be running the following setup:

stock 13B GSL-SE block
S5 intake manifold from N/A
S4 exhaust manifold from TII
Haltech E6x
Tail Blowoff
255lb fuel pump
1000cc and stock injectors for fuel
alot of other parts but you get the jist of it.

It gets under way June 6th so I'll send pics and tell you how it goes along the way.

 

darn newbs. s3 and s4 have the same compression ratio diffrent rotor weights and about 10 degress different port timing. directfreak runs a cosmos engine and is nowhere in any similar to a gslse engine except its a 13b and has rotors. On a serious subject like this one research a little more before giving advice. If you plan on running 5 psi the stock fuel pump and injectors will bareley cut it. First problem is I doubt the Mass airflow sensor will flow engough for 8 psi. not inless you plan on converting the whole injection to s4 injection...

 

and you say i need to research... the megasquirt ELIMINATES the afm... its gone... bye bye... no more... and yes i plan on converting the whole injection to S4...read my posts... i said i was swapping the upper, lower intake, fuel rails, and injectors... 460 primaries and 680 secondaries...

 

I hope you plan on rebuilding and putting in new apex seals. Plan you fuel and timing right or "kabooom". You seem to have picked some good parts with one exception, you need low compression rotors, use s4 if you want lots of boost or s5 if you want less boost but great driveability.

 

dude with 5 lbs... i shouldnt blow anything if i have the fuel... any more then 78 lbs i can kiss my engine good bye...

 

If your gonna rebuild, get lower compression rotors anyway. To get more power later all you do is add boost.

 

Its all in tuning I have seen many use higher compression , to get more power with less boost. But there will be more chance of detonation. The only drawback is your peak power will come sooner. Not sure if you covered the injector debate, the system is designed to use high impedance injectors. The difference between the 2 is the volt range operation of the 2. Least you are doing it the smart way and getting aftermarket fuel computer to bypass the afm. That or I just don't know what I am talking about and make no sense at all.

 

HERE's what i'm runnin
Stock compression (GSL-SE) about 50K on rebuild
3 inch turbo back exhaust
tial waste gate
HKS SSQ BOV
680cc primaries
1100cc secondaries
HKS injector controller
STOCK ECU- LOCKED DIZZY and timing retarted 10deegres
7 PSI low boost
12PSI high boost( Only when needed )
oh and a walbro fuel pump and mallory FPR

 

Oh yeah And I 4got about that S4 turbos w/ aftermarket exhaust= U HAVE TO PORT THE WASTE GATE! If Ur not running aftermarket! If U hollow the cats or get different piping A stock S4 turbo is allways going to get BOOST CREEP!!! So do this or UR engine will go "POP" Soon!