Honda stock injectors with Turbo

[stevharr]

Hi,
I have recently purchased the kit outlined below for my S2000 and have seen people saying on other threads that the stock injectors should be upgraded when turboing Hondas. This kit specifies that the stock injectors can be used with this kit. Should I UG the injectors for an S2000 or can I "trust" the kit supplier?

Rev Hard Stage 2 Turbo Kit
Honda S2000
Use: Street/Track
Part #: RHSTGII
MSRP: $4,999.00 Boost Level: 7psi
Injector Size: Stock
Horsepower/Torque: +120 / 285 ft/lbs

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Product Overview: Rev Hard Cast Iron Manifold
T3/T04E Hybrid Turbo
Turbo efficient to 450hp
Rev Hard Intercooler 28x6.5x3
TiAL 38mm External Wastegate
Vortech Blow Off Valve
2.25" Aluminized Mandrel Bent Piping
2.5" Downpipe
Billet Map Diffuser (check valve)
Rev Hard FC (Fuel Controller)
Silicone Hoses & Clamps
Steel Braided -3 Oil Line
Oil Return Line
Oil Filter Relocation Kit
High Pressure Fuel Line
High Pressure Silicon Hose
Necessary Vacuum Tee's
Necessary Vacuum Lines

[pornstar]

it always depends on ur fuel u "require", ie does ur engine need more fuel than the injectors/pump system can give. If u want no mess no fuss no bull**** answers, go to speak to adrian at toda racing

[Weq]

out of the box, ur kit is made for stock injectors at stock boost levels. It comes with a FMU device which increase fuel pressure dependant on boost. Its not the best solution, but it works. these kits are reliable. They dont produce the biggest HP, but will meet ur goals i suspect.

I say next port of call for u is to look at larger injectors and an aftermarket ecu of some description when u get sick of the power.

[saxman]

fmu's are VERY poor devices. Yes, it will work, however, it is far from a safe and reliable set up. I certainly wouldn't under any circumstances turn up the boost.

Frankly, I think running a turbo set up without upgrading injectors and a tuned ecu is a dumb thing to do.

[yourfather]

yet another 'can i run xyz turbo' with stock fuel system thread, mr saxman.

[stevharr]

yet another 'can i run xyz turbo' with stock fuel system thread, mr saxman.

Well, I did search for this particular subject for S2000 before posting, but found none. I thought that was the purpose of the forum... to ask questions.

[stevharr]

fmu's are VERY poor devices. Yes, it will work, however, it is far from a safe and reliable set up. I certainly wouldn't under any circumstances turn up the boost.

Frankly, I think running a turbo set up without upgrading injectors and a tuned ecu is a dumb thing to do.

ok I have taken this on board. Is it simply a case of upgrading the injectors when fitting the kit? Don't have the budget for the ECU at the moment, but could add this down the track. I want to make this as simple as possible - but obviously don't want to cut corners and ruin a perfectly good car, which is why I am asking these questions that I'm sure you are sick of answering.

[saxman]

the ecu and the injectors need to happen at the same time.
If you run much larger injectors with the stock ecu, you're just going to be dumping a lot of extra fuel and the car will barely run.

I wouldn't put the turbo and stuff on until you can afford the ecu, personally.

Will it run with the fmu? sure.
Will it not blow up? probably, at least for a little while.
Is it a good thing to do? no.

There are lots of people out there running fmus on low boost set ups without a problem. There are also lots of people out there with blown engines as a result. With an engine as expensive as the f20c, with that high of compression, etc, I personally wouldn't chance turboing it without proper fuel tuning and some sort of ignition control.

[stevharr]

the ecu and the injectors need to happen at the same time.
If you run much larger injectors with the stock ecu, you're just going to be dumping a lot of extra fuel and the car will barely run.

I wouldn't put the turbo and stuff on until you can afford the ecu, personally.

Will it run with the fmu? sure.
Will it not blow up? probably, at least for a little while.
Is it a good thing to do? no.

There are lots of people out there running fmus on low boost set ups without a problem. There are also lots of people out there with blown engines as a result. With an engine as expensive as the f20c, with that high of compression, etc, I personally wouldn't chance turboing it without proper fuel tuning and some sort of ignition control.

I see. New injectors and ECU will be about an extra $2000-$2500 right?

Would someone with basic mechanical knowledge be able to replace the injectors, or is it not that simple? AEM make an ECU for the S2000 and the windows based sw seems like it would be fairly easy to use, even for a layman, like myself. Although I have read somewhere else that tuning should be done by someone that knows what they are doing.
I am keen to get the kit fitted because I have paid a lot of money for it, but by the same token, I don't want to be forking out for an new engine. So if the consensus is that ECU and UD'd injectors are the way to go, the kit will have to gather dust until I can get the other parts.
What is the problem with FMUs? do they have a low MTBF? What would happen if one were to fail?

[saxman]

I don't really know the cost of an ecu for the s2000... I do most of my work with the lower model hondas That, and I'm in the USA, so everything is different


Injectors are fairly easy to replace. Certainly not a difficult task.


The probablem with fmus are that basically it's just a boost dependent fuel pressure regulator. For every psi of boost, it boosts fuel pressure by a given amount. A 10:1 fmu will boost fuel pressure 10 psi per psi of boost, a 12:1 12 psi, etc. This has a couple major problems. One, being that you have no control over fueling. A psi of boost at 3000 rpm is going to require different fueling than a psi of boost at 6000 rpm.(and while it will get different fueling, because it's adding fuel pressure to a base injector setting for 0 psi/whatever rpm, it's still very innacurate.) You can't go adjusting as needed either, so it's pretty much a point and shoot and hope all is well scenario. Then there's the whole problem of using a 10:1 fmu for example, at 7 psi, you're running 70 additional psi, on top of the 40 or so psi that's ran stock. 110 psi on a system designed for 40 or so psi has lots of problems. Can lead to catastrophic injector failure, which means no more motor. Then there's the whole lack of timing control. To safely run a turbo, you need to retard the timing during boost. Running stock timing under boost is just begging for detonation, and as such, no more motor. Personally, I'd just sell the fmu(and the map diffuser, as you only need that with the fmu to keep the ecu from seeing boost), and put the money towards injectors/ecu.

[stevharr]

I don't really know the cost of an ecu for the s2000... I do most of my work with the lower model hondas That, and I'm in the USA, so everything is different


Injectors are fairly easy to replace. Certainly not a difficult task.


The probablem with fmus are that basically it's just a boost dependent fuel pressure regulator. For every psi of boost, it boosts fuel pressure by a given amount. A 10:1 fmu will boost fuel pressure 10 psi per psi of boost, a 12:1 12 psi, etc. This has a couple major problems. One, being that you have no control over fueling. A psi of boost at 3000 rpm is going to require different fueling than a psi of boost at 6000 rpm.(and while it will get different fueling, because it's adding fuel pressure to a base injector setting for 0 psi/whatever rpm, it's still very innacurate.) You can't go adjusting as needed either, so it's pretty much a point and shoot and hope all is well scenario. Then there's the whole problem of using a 10:1 fmu for example, at 7 psi, you're running 70 additional psi, on top of the 40 or so psi that's ran stock. 110 psi on a system designed for 40 or so psi has lots of problems. Can lead to catastrophic injector failure, which means no more motor. Then there's the whole lack of timing control. To safely run a turbo, you need to retard the timing during boost. Running stock timing under boost is just begging for detonation, and as such, no more motor. Personally, I'd just sell the fmu(and the map diffuser, as you only need that with the fmu to keep the ecu from seeing boost), and put the money towards injectors/ecu.

just reading that paragraph made me quite nervous. I really like my car, and being alive. So I think that I will do the lot in one go and the Mrs will have to have her moan about the extra money and how will we feed the fish blah, blah.

So just to make sure I've got this straight:

1) Purchase new injectors (What size and make)
2) Purchace ECU for S2000
3) Have Turbo kit fitted with new Injectors and ECU
4) Have the car tuned (by myself or someone who knows what they are doing?)
5) Sell the bits that I don't need on Ebay
6) Enjoy the ride

[tinkerbell]

just reading that paragraph made me quite nervous. I really like my car, and being alive. So I think that I will do the lot in one go and the Mrs will have to have her moan about the extra money and how will we feed the fish blah, blah.

So just to make sure I've got this straight:

1) Purchase new injectors (What size and make)
2) Purchace ECU for S2000
3) Have Turbo kit fitted with new Injectors and ECU
4) Have the car tuned (by myself or someone who knows what they are doing?)
5) Sell the bits that I don't need on Ebay
6) Enjoy the ride

you could change the order and add a step (3):

1) Have Turbo kit fitted
2) Have the car tuned
-3) ask tuner if the fueling is adequate/what opinion on improving

if improvements required:
4) Purchase new injectors (if recomended by tuner (ask tuner what brand)
5) Purchace ECU for S2000
6) Sell the bits that I don't need on Ebay
7) Enjoy the ride

i recommend you speak with Adrian at Toda Racing Australia about the install and tuning, he has done a few turbo S2000's i think...

http://www.ozhonda.com/forum/member.php?u=83