Hello there, i just buught a low milage EJ207 block that im about to send to a machine shop to let it have a CDB conversion.

The car i drive right now is a Type-R 1997 (ver3) GC8, so i have no idea how the AVCS works, so now when i have a AVCS ready block do i need 207 heads aswell or is any EJ20 heads fine?

Is it only the Cams that is AVCS or is it the heads aswell?

I wont use Subaru cams, and nothing in the heads will be OEM so i wonder is there aftermarket AVCS cams or what should i do here?

And if i dont use the AVCS functions what should i do with the block then?
Basicly some general tips to what to do

 

V3 heads will fit straight onto the EJ207 block, Just get the right head gasket to make sure you get the correct compression ratio, In order to have the AVCS heads funtioning properly you would need the STi ecu or an aftermarket one that is capable of controlling it plus some addition wiring, Far easier to fit the GC8 heads IMO.

 

Hi there

As above Gaz said,you will need different ECU which can allow you control AVCS.About the cams,depends on the yours bhp target,if you are not going above 500bhp I would say they're OK

Technically you can use too JDM AVCS heads too without the plugging them to ECU,just they're will be in retarded position

Aftermarket AVCS cams you can use Kelford,GSC,Cosworth etc.We are using Kelford

Jura

 

Don't forget the avcs heads are a differnt bolt pattern to the V3 heads, sounds a minor thing but takes alot of work to convert to the correct inlet manifold.

 

Thanks for the answers guys,
So basicly if i use AVCS heads without having it used in the ECU it will basicly work as NON AVCS heads?

I will go for more than 500bhp, my goal is around 600bhp prefer 500ish WHP,

About the bolt pattern for the intake manifold, couldent i just get the intake manifold from a 04 for example with the AVCS heads stock if i go for AVCS heads?

Because i rather not take parts from my current engine as i will drive it until the other engine is 100% complete and ready to get droped into the engine bay

 

It's not that simple, you would need to re-wire the engine wiring to match your ecu, if your not going to use the avcs, then I would put the effort into your V3 heads, get them ported with some good cams, valves etc.

 

I see, So any GC8 heads without AVCS it is then , i guess no GC8 had AVCS?

At what year did AVCS come?

best regards!

 

The choice is yours, avcs does help spool, but you will have alot of work to change to this setup in your car. No GC8 had avcs, they came with the new age STI from 2001. There is nothing wrong with the STI V3/4 heads at all, they are used on alot of high power engines.

 

Hi there

If you are putting effort adding cams etc I would invest the money to the ECU which can control AVCS in first place(have look on the Syvecs S6)

At 600hp I would go down the route of the AVCS just due you will gain on spool,going with non AVCS at 600hp not sure if I would go down this route

Second point,if you are thinking again to run 600hp on 2.0L not sure if I would go down this route,just due will be laggy like with AVCS or non AVCS,with 2.1L or 2.35L can be different story

Jura

 

Ahh sorry, to be clear it will be running a 2,1 liters and the heads will be rebuilt with everything, valves springs retainers cams etc, im just unexperianced when it comes to AVCS i will probably do my own Engine wiring so the AVCS could maybie be worth a shot anyways!

So what more ECUS do we have out there that can controll the AVCS?
And im aware that even a 2,1 liters will be a bit laggy with a turbo of the size needed to reach 600ish but i love reving!

Best regards!

 

Another thing i wonder, is there any difference between the EJ20 heads? i mean lets say the heads from a EJ205 and EJ207 more than the internals in the head?

Got one more question about the AVCS heads aswell, if i decide to go AVCS do in need some special cam sensors / other stuff? or are they 100% guided by the ECU? i mean installation is just the oil thing and then to the ECU who support AVCS?

 

Hi there

Have look on Syvecs S6PnP,this ECU can control AVCS and have few features which you can use on yours like full knock control,wideband and datalogging plus is available on yours model and all those features are free for no extra fees

If you are looking to do your own engine loom I would go down the route of the Syvecs S6GP,usually is cheaper than S6PnP

Others ECU which can control AVCS are like MoTeC,SimTek(AlcaTek),Hydra and few others,but you must know on some those ECU's are those features for extra


Jura



About the EJ205 heads,if they're JDM in this case are Big Port AVCS(just cams and other bits are not as good as on the JDM STi heads or even UK STi),if they're UK/USDM in this case are non-AVCS

EJ207 are different in most cases,JDM Big port heads are regarded as best heads,about the internals in the heads,cams are better in the JDM,plus rev limit is 8250RPM etc.

About the sensors(solenoids),they're should be same for EJ207,for EJ257 are different

Have look on this,there is threads with I/O pinouts

http://www.syvecs.com/forum/viewtopic.php?f=6&t=137

http://www.syvecs.com/forum/viewtopic.php?f=6&t=401


Just sign in on the Syvecs forum and I'm sure people will able to help you with wiring etc



Jura

 

Thanks again Jura very helpfull! now things is starting to get clear to me

So all EJ207/205 etc have same cam sensors regardless if they are AVCS or not?

 

Yes are same if they're AVCS,only JDM EJ205 has have AVCS and not sure if UK Blobeye WRX has have AVCS,but I'm sure someone this will confirm in later stages

Regarding the sensors,you can buy them cheaply from breakers,but when we are bought our JDM heads,sensors has been there and plus all oil feeds/banjo etc


Jura

 

Okay i see by the way do you have any idea of how much better the JDM Ej207 heads V(7) also known as JDm big port head is?

Any flowcharts that one compared to others?

 

Hi there

As you are seen on few big hp builds,there are only used JDM Big port heads(in most cases),although on on 2.35L(stroker'd EJ22T) some people prefer 2.5L heads(like WRX or STI)

No flow charts,but you can have look on the Nasioc there should be few threads on that


About the cam gears,they're different,you will need AVCS cam pulleys/cam gear pulleys


Jura