Larger fuel pump, Would i need fires with that. Options

[urbandork]

If i get a larger fuel pump and larger injectors will i need to get a fuel presure regulator or n e thing else? I figured that since its a larger out put pump it might need some other things to suport it.

thanks.

[jgreening]

You will need something to control the fuel. Preferably a standalone EMS but a fuel controller will work. A regulator may be needed for high horsepower applications or if you wanted to bump up your pressure to maximize power on injectors that were not big enough. There are limits to running higher pressures though.

[urbandork]

so i cant just run larger injectors and a larger fuel pump?

[jgreening]

so i cant just run larger injectors and a larger fuel pump?
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Re-read my first post. You can run just a larger pump. However, you CANNOT run larger injectors without something to control them - at least without it running poorly from an overly rich condition. There are a few guys on the MR2 board that claim to run 550's on the stock 3s ECU with no problems but they are definitely the exception. Running excessively rich causes problems over the long run.

The stock ECU has been programmed to run stock injectors. It is set up to open the injector for a certain duration under various RPM, temperature, and load conditions. If you use larger injectors and a stock ECU, you will get too much fuel.

The whole point of running larger injectors is to maximize performance. It just doesn't make sense why someone would want to put larger injectors in and then not utilize them properly by tuning the A/F ratio correctly.

[urbandork]

humm. well would it made a diffrence if im boosting and using an msd btm? Ive been reading at it seems that when running a 5sfte larger injectors and a larger fuel pump so it wont run lean. But what i havent seen are ppl talking about the a/f mixutre and how to change it?

This post has been edited by urbandork: Mar 11, 2005 - 2:11 AM

[Newbie]

I thought the 3rd generation of 3SGTE's used the 550cc injectors stock?

[Hanyo]

it would be best to control the fuel mixture. because the stock fuel mixture map is designed for no boost. So even with the upgraded fuel pump and injectors. The ecu will still dump fuel where it is not needed, and lean out where it needs fuel.

People talk about changing fuel mixture all the time with the apexi fuel controler, and greddy emanagment.

[jgreening]

I thought the 3rd generation of 3SGTE's used the 550cc injectors stock?
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Actually 540's but close enough. But the 2nd gens come with 440's so thats what I meant by "upgrading" to 550's.

This post has been edited by jgreening: Mar 11, 2005 - 8:57 AM

[lagos]

if you have a 3sgte and want to upgrade to 550s, you would need an fpr and some type of piggy back ecu controller to tune the car with.

a btm works by retarding the timing of the car based on boost. you dont need to do that on the 3sgte because its a facotry turbo car.

[urbandork]

so on a 5sfte set up what do i need?

225 lph fuel pump
330cc injectors
BTM to retard timing
and
a piggy back ecu

????

i