legacycentral bbs

I'm wondering how flexible the factory ECU is. Here is what I was thinking of...

Swapping on my VF24 from my STi. Swapping in it's injectors and MAF sensor.

I haven't checked compatibility on the parts and I am assuming that I can get a tight enough right angle for the turbo inlet. Right now I don't have the time to sit down and figure out the Subaru engine triggering system to install a psitech ECU.

I assume at some horspower number the factory MAF runs out of capacity. So I was thinking that the larger capacity STi v4 MAF sensor should have this needed space. Unfortunately this would mean running lean on the factory injectors so I think I would need to do the injector swap at the same time. Many carmakers will scale these parts in unison to cut down on R&D time for cold startup and driveability.

If I do all this I will obviously be sticking a wideband on to make sure the mixtures are good but I wonder if anyone has tried a combination like this.

-Michael

Well, I as well as quite a few others are running 16g's on oem engine management and injectors. So yes it can be done. The MAF will hit the rail very quickly (around 12 psi on the 16G) so that is an issue.

Your STI injectors will work but you'll need to drop them into 92-94 N/A rails because they won't fit the EJ22T rails.

Wait a second, I just reread your post and now I'm wondering, where are you from? NZ or AUS maybe? We never got the early STI's that came with the VF24 here in the States so that's what I'm assuming. I'm really not familiar with the Liberty RS ECU or anything so I couldn't say if guys are running big turbos on the OEM ECU. If you are from over there and have the RS I would suggest asking the guys on LibertyRS.com or whatever.

Actually the STi engine was probably the 2nd STi swap in Canada. Done long before the 2002 WRX hit our shores and it definitely collected its fair share of V8 kills.

Times have changed and now the once rare STi swaps can be found at any importer. My Impreza was crashed into a new driver who forgot to look for oncoming cars before making a turn. Some of the engine parts survived and this put a turbo, MAF and fuel rails in my spare parts box.

The 1998 STi injectors were 580cc (approx) and they were side feed. I will dig up the MAF and see if its plug and markings are similar.

-Michael

STi is also a drive-by-wire system, electronically. Wouldn't the MAF be incompatible because of this?

Ah, Canada, OK. There would be less confusion if you had you location filled in.

It also sounded like you actually had an early STI when reading your post, not just the motor from a swap.

Not sure about the injectors but I know that the real old side fed and new side fed both fit in the 92-94 EJ22 N/A rails but not the EJ22T rails.

I don't think the MAF will work with the EJ22T's OEM ECU but you can try, it's worth a shot.

The older STi engines had normal throttles. I wasn't planning to swap the throttle over but I may port the heads and then swap them on with new pistons. I am not prepared to do that yet as all the pulleys and covers were smashed in the crash.

I wasn't aware that the STi sidefeeds wouldn't swap in. Maybe if that is the case then I can swap the fuel rails and everything. If that's still not an option then I guess I could machine some new fuel rails and go with a DSM type injector. Too much work! Getting that rusted VF11 off will be enough trouble.

Where do you guys usually shop for used 16G's? This would be easier than my VF24 as it already has the 90 degree inlet.

-Michael

The fuel rails from the 92-94 NAs accept nissan 370, 440 500 and 820 cc injectors.

I don't know if the rails will fit but the injectors should fit in the 92-94 N/A rails.

I don't think the MAF will work, the Legacy SS ECU and MAF are a good bit different than the JDM stuff. Still I'd give it a try and see.

If I ever get my car running right I'm going to try and make a restrictor for the MAF to scale for bigger injectors and get more range out of it.

where you at in canada? also you need the rails from a n/a and they will drop right in. also your going to need to tune the injectors cuz your car will bog, i used a greddy-e-manage. it ask you do you have bigger injectors you put the size in an boom it % them for you.

91legacy_sleeper wrote:STi is also a drive-by-wire system, electronically. Wouldn't the MAF be incompatible because of this?

Why do you say that?

The Maf won't work just swapping it as is, the STi uses a Denso Sensor.

Ran some dissapointing times at the strip tonight. Now I'm more anxious to make more power. 15.43 best time

I guess I may just skip all the stock subie management and go directly to my standalone. My MAF is getting a little dodgy even after cleaning it.

For those who wonder I'm in Gatineau Quebec.

-Michael