i just had a idea about using 2 spfi throtle bodys like a duel carb set up and 2 computers and 2 o2 sensor or if one computer could triger 2 throtle bodys or injectors and custom intake manifolds and water crossover set up

Many cars run on dual ECUs, Until the late 90's practical ECUs did not exist that could run a V8 at high RPMs so some manufacturers used two ECUs to run it as separate 4 cyl engines. I had a 348 that had dual ECUs. Sometimes the ECUs were linked and sometimes not, and sometimes when they were linked they talked, and sometimes not. So the short answer is yes you can, but also, why? Your SPFI TB is not really the bottleneck in flow, and your going to have to deal with the built in maps that may not play well with low CFMs for a given RPM, it could have driveability issues. And you don't have any of the problems that a dual ECU setup was used to solve (ability to run at XXXX RPM). You could do it just to do it, but don't expect any gain.

the air wouldent have to make 2 90º turns it would be a straight shot and have gravity on its side as for the rest i dont know im in the process of quick and dirty rebuilding a basicly junk motor just for fun for a back burner project i have floating it would never see the street or smog and reliability isent a factor but would make a good test platform all i need is another throttle body and computer

From what I have read from MANY past threads about modding these engines for performance, the bottle neck is the intake port and size and lift of the valves.  The best way to get a significant power increase is to adapt an EJ engine into the car.  Similar amount of work, and something like 40% power boost, with all of the reliability of the EJ engine.

i dont have 4 ej motors laying around to play with only ej i have is in a different project

I understand, not having an EJ.  You wouldn't need 4.  Only 1 working one for what I suggested.  Plus the harness & computer for the EJ, which, yes, would be stuff you have to find / buy.

 

It depends on the end point of the project.  If you want to make a 1 off custom, with stuff you have, I get that.  If you want a big power increase, EJ.  Both are big projects time wise. 

 

For experimental FI projects, look at Megasquirt.  Open source FI engine control system.

by the time they got around to "fixing" the ea...they made the EJ. the heads are going to hold up the flow long before you see benefits from two TBs

It should be doable with one ECU. You would need to find injectors that would fit the TB, but with half the flow rating as the single original. You're still going to have flow issues in the heads as pointed out before, so on a stock engine, you won't see much if any, of a gain. It'd be interesting to try, but I don't see it working well.

ahhh the ol' "do an EJ swap" instead of a simple answer. hes asking a question and getting no answers.

 

YES, do it, you may get killer throttle responce and a few HP up high, maybe some torque gains down low. Plus it sounds cool! Try it with one ECU just wire them TB's together.!

ahhh the ol' "do an EJ swap" instead of a simple answer. hes asking a question and getting no answers.

 

YES, do it, you may get killer throttle responce and a few HP up high, maybe some torque gains down low. Plus it sounds cool! Try it with one ECU just wire them TB's together.!

 

The ECU will be monitoring O2 sensor for mixture......so you'd just get 2 TB's pumping half the amount of gas they normally would.

 

Nightmare of a Fab project......The intake boot would have to "T" toghether so both would pull through the MAF.

 

IF you were to do this it would require custom fuel management or it will never run right.

 

 

So....in this case.....the EJ swap IS the "simple answer"

Edited November 17, 201411 yr by Gloyale

Yeah, but I was trying to give the guy a little hope. lol Oh, and dual ECU's? Not in American cars at all, and only high end Euro models like Ferarri and the likes. Aftermarket world seems to like them. Why I don't know...

just wondering............who said ej it? all i said was two TBs wont getcha to shakeys pizza

a better idea would be to pay someone to make you sime billet adapters and dual weber that sucka. who needs ecus then youve got a weber on each head?

the fab nightmere is the most apeelinng part of it for me i have a full metel fab shop to play in and im retiered so ive got the time and material and tools and lots and lots of scrap metal i was thinking of duel carbs but then had the duel tbs idea instead the problem as i see it is the ecu is fireing for 4 clyders not 2 and i know these motors dont like the extra gas but maybe port the hell out of the exaust and polish them up it might be able to burn the extra gas maybe not i dought it would last long but might be a fun build im thinking duel ecus because i dont think one computer can moniter 2 o2 sencors i dont see a problem with sharing a maf signal other than it wouldent read the air flow right it would be reading air for 4 cylinders not 2 so it would probably need 2 of everythin to even run i know this is in the catagory of why the F would any one want to do this but hay its just a idea

Interesting idea. The eg33 had dual throttle bodies but they are combined into 1 part/mani. Both Porsche and Ferrari had split throttle body boxers, makes more sense with 6/8/12 cylinders for sure..

But for a split dual spfi setup.. megasquirt and dual map sensors would probably be the most (cost) effective. I can't say you will see much of a performance increase but it would be a cool project.

 

Or something ridiculously custom like this could be cool too: (bmw m60 with some superbike tb's)

 

Edited November 18, 201411 yr by Ibreakstuff