Power increase questions

Fozzy

Petrolheads
Hi folks,

I’ve been collecting parts for the Foz as of late and at the moment, I have the handling pretty much sorted and am close enough to start upping the power. Currently it’s a JDM ej205 block with a vf28 and standard injectors. Still running stock factory settings. I’m looking to go to about 300bhp. I have the ECU sorted and am waiting on a hks knock/AFR sensor will be getting a decat downpipe fabbed up for this (may go the whole way to the back box) and will be changing the belt and water pump, plugs etc just to be sure.

I’m looking to source a boost controller now but have two questions;

1) will I need a 3 port solenoid for this level of power with the vf28

2) will I need to upgrade the injectors - if so, which would be best suited and who supplies at a good price?


Thanks lads
 
Probably best to ask all those questions your mapper of choice. As much as l gather 3 port is not needed. As about injectors l don't know what you have but sti pink could be gotten very cheap and they are good for high 300's :54:
Anyway if you looking l should have brand new 3 port somewhere
 
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not all cars will perform well on the 2port though - I would normally advise if your swapping the turbo to swap to a 3port as well so that the best results can be had. Any car with a 2port will benefit from a quality 3port once it's all setup, the 3ports ability to prevent pressure getting to the wastegate (vs a 2port only able to bleed an amount of pressure off the line) will always help the spool up and improve the top end response (assuming of course the turbo is capable of meeting the demand).

You say "I have the ECU sorted" - what did you end up going with?
 
not all cars will perform well on the 2port though - I would normally advise if your swapping the turbo to swap to a 3port as well so that the best results can be had. Any car with a 2port will benefit from a quality 3port once it's all setup, the 3ports ability to prevent pressure getting to the wastegate (vs a 2port only able to bleed an amount of pressure off the line) will always help the spool up and improve the top end response (assuming of course the turbo is capable of meeting the demand).

You say "I have the ECU sorted" - what did you end up going with?

I’m not changing the turbo at this point (though will be later) but there’s a vf28 in there since before my ownership. I think I may as well go with the three port for future proofing anyway. As for the ECU - the one in the car can’t be mapped in Ireland as no-one with a 4w dyno hasn’t the software - Aonghus Power tried his best but no go.

I have acquired a mapped Forester STI ECU from Japan and also an Apexi P-NBC piggyback unit so the plan is to add my AFR/knock setup, boost controller and do the exhaust work, then get it mapped with either the stock ECU tweaked by the Apexi or, if it’s better the mapped ECU again tweaked by the Apexi unit

After speaking to a few guys in Oz I think I’ll Alison upgrade to 550cc side feed injectors - when I change the turbo later on I will do a top feed conversion but no need to do that at this stage I think
 
I’m not changing the turbo at this point (though will be later) but there’s a vf28 in there since before my ownership. I think I may as well go with the three port for future proofing anyway. As for the ECU - the one in the car can’t be mapped in Ireland as no-one with a 4w dyno hasn’t the software - Aonghus Power tried his best but no go.

I have acquired a mapped Forester STI ECU from Japan and also an Apexi P-NBC piggyback unit so the plan is to add my AFR/knock setup, boost controller and do the exhaust work, then get it mapped with either the stock ECU tweaked by the Apexi or, if it’s better the mapped ECU again tweaked by the Apexi unit

After speaking to a few guys in Oz I think I’ll Alison upgrade to 550cc side feed injectors - when I change the turbo later on I will do a top feed conversion but no need to do that at this stage I think
I think your over-thinking things and making issues that you dont have.

If early 2001 on Jecs ECU then can be mapped with Ecutek no issues

If late 2001 then on Denso and also can be mapped without issue.


If someone has installed a jdm board prior to import likes of prova or mines etc. Then may be an issue accessing but just another 2nd hand ecu and map away.

Imo the Apexi road have went is wrong way about it when have likes of the latest Link G4 ECU with anti lag and launch control available for €999.00

Injectors. 440cc be fine with vf28. No need to change to top feed for an original engine.

Sent from my SM-N910T using Tapatalk
 
I think your over-thinking things and making issues that you dont have.

If early 2001 on Jecs ECU then can be mapped with Ecutek no issues

If late 2001 then on Denso and also can be mapped without issue.


If someone has installed a jdm board prior to import likes of prova or mines etc. Then may be an issue accessing but just another 2nd hand ecu and map away.

Imo the Apexi road have went is wrong way about it when have likes of the latest Link G4 ECU with anti lag and launch control available for €999.00

Injectors. 440cc be fine with vf28. No need to change to top feed for an original engine.

Sent from my SM-N910T using Tapatalk


Can’t find anyone with a 4w dyno and an ekutek license - no one wants to pay for one as they’re not used widely.

I got the Apexi for €80 delivered from Japan so it’ll do for now anyway - wasn’t really looking to spend big for an aftermarket ECU at this point.

Also, one of the Oz lads with the same car maxed his injectors at 270bhp so it’s for safety more than anything and they’re not expensive.

As said, won’t go top feed at the moment but maybe in future if I change turbos go for more power and need different injectors
 
Can’t find anyone with a 4w dyno and an ekutek license - no one wants to pay for one as they’re not used widely.

I got the Apexi for €80 delivered from Japan so it’ll do for now anyway - wasn’t really looking to spend big for an aftermarket ECU at this point.

Also, one of the Oz lads with the same car maxed his injectors at 270bhp so it’s for safety more than anything and they’re not expensive.

As said, won’t go top feed at the moment but maybe in future if I change turbos go for more power and need different injectors
440cc wont be maxed at 270bhp.

Sent from my SM-N910T using Tapatalk
 
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