TinyFC87

i have a 90 TII with 45k miles on new motor. i want to upgrade for more boost. i have been working on replacing vac lines and stuff all weekend, and have removed injectors. i am going to get them cleaned and tested to make sure they are in perfect running condition.

now i want to know whats the best way to go here, should i just put in some 720 secondaries and get SAFC to tune them? or do i really need those injectors at all, i only want to run about 10-11psi daily driven. i would need boost controller to up to 10 PSI correct?

do i need to get any thing else like an Adjustable Fuel Pressure Regulator or upgrade my fuel rails?

Thanks

RotaryEvolution

iTrader: (30)

you won't need to go with 720's for 10-11 psi on a stock turbo but i would suggest upgrading the fuel pump.

you will definitely need a way of tuning the fuel to add more so an SAFC or something similar is needed.

you will need a manual or electronic boost controller to up the boost, yes.

no you don't need a fuel pressure regulator, changing the fuel pump will raise the flow and pressure slightly to pump more fuel through the injectors, it is like upgrading to a slightly larger injector. you can install a FPR to lower the pressure to stock though so you won't have to lean out the injectors for the higher pressure/flow pump but that is personal preference and i tend to want to leave the fuel delivery system as it is until you really need to modify it.

if you have stock exhaust you won't see those kind of boost numbers so that is something to take into consideration, if you don't have free flowing exhaust you will need it and if you do go free flowing then you will want to port the wastegate or you will have to restrict the exhaust with a high flow cat or tapering down the diamter of the piping to keep the boost down. too much boost is not a good thing without supporting mods.

TinyFC87

well here are my mods i forgot that part.

- 3" downpipe
- 3" Apexi N1 Exhaust
- No cats
- Walbro 255
- FCD
- BOV
- Autometer Boost Gauge
- Fluidyne radiator

bigdv519

iTrader: (3)

How much boost are you at now, with the mods listed???

TinyFC87

yah thats the thing. when i installed the boost gauge it was reading 10psi all the tme.so thats why i wanted to upgrade the fuel to compensate for extra boost. but after i installed the FCD and walbro its at like 6-8psi now.\

i have also heard about porting my wastegate or getting bigger one. is this a must or what? am i good without it? i just want to run low 14s high 13s daily till i save up more money for turbo upgrade.

bigdv519

iTrader: (3)

10 psi all the time???...like at idle, at part throttle, at WOT, and in ever gear. What about at cruising speeds, 65, 70 mph, were you at 10 psi.

Get a manual boost controller, set it to 10-11 psi, and take it to the track. Then before anyone flames you for starting a thread on How-to-install-a-MBC, search for MBC.

TinyFC87

no it was just 10psi at WOT and only in 2nd gear and up. 1st gear only ahd like 7 psi

RotaryEvolution

iTrader: (30)

install a SAFC and a boost controller, porting the wastgate is a good idea but if you are holding at less than 10 psi right now your intake/exhaust might not be flowing as well as it could so it is limiting it so porting the wastegate would be an anticipation mod.

TinyFC87

i have a cone filter on the intake, would the TID mod help a little with air flow or should i just get a hard pipe?

and is the wastegate porting DIY or should i go have it done elsewere? if not would replacing it with aftermarket wastegate be easier or cheaper? and what size, if its actually needed

gingenhagen

check the thread in the archives on wastegate porting. You can do it yourself. Aaroncake also had a recent thread with pictures of a ported wastegate.

TinyFC87

thanks guys for the information. i would have an rx7 guy around here help me out but they are all FD guys and everytime i ask them questions tehy are like i dont know i have FD. lol