Questions regarding ECU upgrade

[loudstealthGT-Four]

Well have decided to upgrade from my factory ECU, to a Link G4. Won't be purchasing ECU until end of Jan/start of Feb, have just been thinking about it for abit, and am abit unsure on somethings.

First off I will give you a run down on my plans, basically looking to make a few more HP from my current setup (only upgrading the essentials), keeping in mind of the future, when I will potentially be looking at upgrading serious parts i.e turbo, cams. Will be looking at around 300-400hp atw.

One thing is Injectors, I need to upgrade them. What I need to know is;
What CC should I go with?
What is the difference between low and high impedence?
Should I just stay with Low Impedence? (Same as Factory)
Are there any advantages between side feed and top feed injectors?

Have many more questions, but will hold off for now

Many Thanks in Advance
Tyler

[Al]

Top feed injectors are a heap cheaper than side feeds. You can get a set of large (720cc, 850cc, 1000cc, 1200cc) top feeds plus the new fuel rail and fittings for less than a set of 800cc side feeds.

[gt4dude]

i think were in the same boat as far as injectors go, we got a side feed rail, so our options are limited as far as injectors go, i think sard make an 800cc drop in 3sgte injector,

or we have to get a top feed rail kit and then we can use almost any injector

the low impedence, high impedence shi t has to do with how much current the ecu injector drives can put out and the resistor pack in our factory loom, some people i guess when they deloom their car also remove those stupid alloy heatsink looking things from their cars and just get high impedence injectors

the other resistor pack is for the fuel pump for idle and decel which i think is a good thing to leave in as it extends the life of your fuel pump

[Heylin]

Been there with the MR2.

Ended up going with SARD 800cc side feed and dual feeding the factory rail, plenty of fuel for 205 rwkw, injectors were running low duty cycle with plenty left in them.

Look out on eBay for good deals on SARD side feeds, WolfKatz also do injector packages and rail options for the 3SGTE, could be good value with the current USD.

AN fittings fuel hoses and custom work can push up the price of a custom dual feed rail.

[gt4dude]

i never got a chance to look at the factory rail,

ive heard theres some casting crap around the inlet and outlet that can be bored out, but whats the bore like inside the rail ?? is it not very wide in there either?

also, dual feeding the rail does this mean you tapped in a new return port between 2&3 or did you just put a T-piece somewhere on the fuel line?

[strx7]

if you changed your inlet manifold (maybe not required) you can use a 3SGE top feed rail and top feed injectors. i used 720cc 12a turbo injectors in a 3sge rail on my 3sgte stroker and an msd external pump, had plenty of fuel in reserve at 270awhp @ 15psi.

[evil_si]

From memory on levinguys i Bored out the factory rail to 3/8, and welded -6 fittings on each end, with a -6 return off the center

[loudstealthGT-Four]

Top feed injectors are a heap cheaper than side feeds. You can get a set of large (720cc, 850cc, 1000cc, 1200cc) top feeds plus the new fuel rail and fittings for less than a set of 800cc side feeds.

I guess it depends on how carried away you get with buying the parts needed, there are some quite spendy items avaliable

i think were in the same boat as far as injectors go, we got a side feed rail, so our options are limited as far as injectors go, i think sard make an 800cc drop in 3sgte injector

Yip not alot of options to choose from.

the low impedence, high impedence shi t has to do with how much current the ecu injector drives can put out and the resistor pack in our factory loom, some people i guess when they deloom their car also remove those stupid alloy heatsink looking things from their cars and just get high impedence injectors

Interesting so to run high impedence injectors I woud need to bypass the resistor??

Ended up going with SARD 800cc side feed and dual feeding the factory rail, plenty of fuel for 205 rwkw, injectors were running low duty cycle with plenty left in them.

Look out on eBay for good deals on SARD side feeds, WolfKatz also do injector packages and rail options for the 3SGTE, could be good value with the current USD.

Awesome thanks for that website, could be quite handy with sorting out everything fuel wise

Will keep an eye out on Ebay over the next couple of weeks, but would definitely prefer new parts.

i never got a chance to look at the factory rail,

ive heard theres some casting crap around the inlet and outlet that can be bored out, but whats the bore like inside the rail ?? is it not very wide in there either?

also, dual feeding the rail does this mean you tapped in a new return port between 2&3 or did you just put a T-piece somewhere on the fuel line?

the bore on the Gen 2 and 3 fuel rail is machined after the rails are cast, I've read (on the interwebs) that it is possible to bore the rail out abit to allow more fuel to sit in the rail.

As for the dual feed, on a Gen 2 fuel rail there is a outlet for a cold start injector, which can possibly be used as a return port. Would need to custom make something up for a Gen 3 rail.

if you changed your inlet manifold (maybe not required) you can use a 3SGE top feed rail and top feed injectors. i used 720cc 12a turbo injectors in a 3sge rail on my 3sgte stroker and an msd external pump, had plenty of fuel in reserve at 270awhp @ 15psi.

Am currently running a sidefeed intake manifold off a ST162 3SGE, so have plenty of room to fit any rail setup in there.

I actually have a complete ST182 3SGE, so might have to do a test fitment on a 3SGTE head to see what I'm able to do, this is probably at the top of list, as it will be cheaper and with abit of research, could possibly have enough flow.

[loudstealthGT-Four]

From memory on levinguys i Bored out the factory rail to 3/8, and welded -6 fittings on each end, with a -6 return off the center

What was involved in doing that, cost wise?

[gt4dude]

just did some googling, it appears you need the same gen the non-turbo fuel rail so for me its currens and celicas, for you its st182s

this is awesome, i never knew about this

[loudstealthGT-Four]

just did some googling, it appears you need the same gen the non-turbo fuel rail so for me its currens and celicas, for you its st182s

this is awesome, i never knew about this

Will make life abit easier/cheaper



In terms of injector size, will 1000/1200cc be to much just to power the engine for now, with plans/an option to run alternative fuels (E85) in the future?

[levinguy]

From memory on levinguys i Bored out the factory rail to 3/8, and welded -6 fittings on each end, with a -6 return off the center

What was involved in doing that, cost wise?

i went for this after seeing what the guys over on mr2oc.com were doing, the alternative was a new aftermarket fuel rail which at the time was 400+

the factory rail only becomes a problem at higher power levels, have a look on the forum and see, i can't remember when, but i was looking for 300kw+ atw when i had my fuel setup done. so it may not be an issue for what you're going for.

i think the biggest thing for you is planning what end result you want, because if you do it bit by bit, changing the tune as you do things, it will work out a lot more expensive then doing it all at once

[loudstealthGT-Four]

From memory on levinguys i Bored out the factory rail to 3/8, and welded -6 fittings on each end, with a -6 return off the center

What was involved in doing that, cost wise?

i went for this after seeing what the guys over on mr2oc.com were doing, the alternative was a new aftermarket fuel rail which at the time was 400+

the factory rail only becomes a problem at higher power levels, have a look on the forum and see, i can't remember when, but i was looking for 300kw+ atw when i had my fuel setup done. so it may not be an issue for what you're going for.

i think the biggest thing for you is planning what end result you want, because if you do it bit by bit, changing the tune as you do things, it will work out a lot more expensive then doing it all at once

Yip I understand that its not the cheapest way to do it in the long run, but I don't think it will work out too bad. This time around I will be upgrading the ECU, fuel pump, fuel injectors and associated parts, and maybe a few other small things. It will then be getting tuned, will then most likely be a long time before I do any other big mods. As the GF and I are looking at buying our first home, so will be tying alot of our funds up in that.

Plan is to get all first round of mods done before we buy the house, which will keep me happy for another while..... maybe