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hey...im knew on the site and i was wondering if im doing modifications..like td06 turbo injectors and other fuel components......will it be best to use 550cc or 650cc because i will be maxing the 550cc out.....??? appreciate it if u guy slet me kno...
 

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...you haven't given any information about your setup ...but it seems like it's common sense. if you're maxing out the 550cc, why WOULDn't you get bigger ones? post your plans here so we can see.
 

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It actually depends on how you plan on controlling them. Bigger injectors have difficulty idling with some EMSes.

If you are going the cheap route (SAFC), then don't get anything bigger than 550s.

Where are there 650 cc/min. side-feed injectors? The next step up that I know of is 800 SARDs from Wolfkatz.com.
 

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mr2secret said:
hey...im knew on the site and i was wondering if im doing modifications..like td06 turbo injectors and other fuel components......will it be best to use 550cc or 650cc because i will be maxing the 550cc out.....??? appreciate it if u guy slet me kno...
stock injectors run out at about 270rwhp to be on the safe side. stock injectors are also 440cc, and a common upgrade is 550cc from the mkIV supra.
 

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flyboy said:
It actually depends on how you plan on controlling them. Bigger injectors have difficulty idling with some EMSes.

If you are going the cheap route (SAFC), then don't get anything bigger than 550s.

Where are there 650 cc/min. side-feed injectors? The next step up that I know of is 800 SARDs from Wolfkatz.com.
Back in the day, some people looking for enough fuel for much more than stock output used to use secondary injector(s) that came on at a certain boost, etc. Greddy used to sell a injector controller called a Rebic III that allowed you to do aftermarket fuel management this way.

What is the disadvantage to this increased fuel supply scenario? Seems logical enough, and when the additional injector(s) are off-line, you've got normal idle/pulsewidth, but seeing as how it's gone the way of the dinosaurs, must be some reason.
 

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The drawbacks would be 4 more injectors, a new fuel rail, fuel system wyes, new injector bosses in the manifold and a regulator that handles 2 inputs.

I reserve judgement on the controller and its transition point until I get to tune such a system. I would imagine the transition wouldn't be smooth. The controller likely doesn't adjust for air temp and such, making it a one-season controller.

Since modern EMSes can now control HUGE injectors, there's little reason to go the staged injection route. New injectors/pump, an EMS and you are for the most part, done.
 

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I would imagine the transition wouldn't be smooth.
That would be my guess as well. The chance for things to go tragically wrong if one set of injectors stopped working and the others didn't would keep me awake at night.

Besides if I can get a great idle on 850's on a modern EMS any one can.
 

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flyboy said:
The drawbacks would be 4 more injectors, a new fuel rail, fuel system wyes, new injector bosses in the manifold and a regulator that handles 2 inputs.

I reserve judgement on the controller and its transition point until I get to tune such a system. I would imagine the transition wouldn't be smooth. The controller likely doesn't adjust for air temp and such, making it a one-season controller.

Since modern EMSes can now control HUGE injectors, there's little reason to go the staged injection route. New injectors/pump, an EMS and you are for the most part, done.
Good answer. Although you wouldn't necessarily have FOUR more injectors; Greddy's old IC kit had piping that had only two bungs, so you would have used one or two big injectors instead of four.

So that is probably another downside - improper enrichment due to the somewhat random amounts of additional fuel that goes tumbling through the throttle body on its way to the individual combustion chambers.

Of course, that's exactly how my water injection system is set up, and I would assume most other people's as well - is anyone running a water injection system with four individual sprayers, going directly into all four cylinders?

I doubt it. I know, proper fuel metering is a lot more crucial than water injection, esp. seeing as how my water doesn't even turn on until around 14 psi.

I'm just talking in circles now. Ignore me. :p

flyboy, in case you're up early on a Sunday, have nothing planned for Superbowl, I was thinking about going for a quick drive up to Estes Park in the MR2 to test the car. Call me if you're interested in coming along.
 

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Dry manifold designs (like ours) have a very hard time with a single-point injector. With our manifold, the entrained fuel can't round the same tight corners that the air can, and you get AFR variations cylinder-to-cylinder.

I designed a port injection system but didn't have the guts to carve up my manifold like that, so I didn't fabricate it. I'm still tossing it around, for grins. My Nemesis has PWM outputs that can be setup to run port water injection like it's another injector.

I can't come along today, I'm feeling sick. I'm sorry. Thanks for the invite, though!
 
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