Board logo

Turbo R1: Which inkectors?
JoaoCaldeira - 21/10/09 at 07:22 PM

Those of you having already a turboed R1, which injectors have you used? Stock ones? Aftermarket? with which turbo? and how much boost?

I'm thinking about TD04HL-16T (Volvo S70 T5) with 5 psi, but I'm unsure if the stock injectors (2003 R1) can cope with that...

Thanks in advance,

hobbsy - 21/10/09 at 10:30 PM

I'm also interested in the reply to this as I have the same turbo (from memory) and the same 2003 R1 engine.

You can get a bit more flow out of them by cheating with an adjustable fuel pressure regulator (whether it be 1:1 or rising rate). This takes a vacuum feed from the plenum / throttle bodies and ups the pressure with boost. You can also change the base pressure.

But equally if anyone knows of larger injectors or the right size/type/impedance that are suitable I'd be happy to know.

afj - 22/10/09 at 10:49 AM

All i know is that they are nippon, around 14ohms and possibly flow around 210cc/hour maybe but ive got someone on the case so ill report back soon (cant you tell i have a desire for booooooost)

T66 - 22/10/09 at 07:39 PM

My old saab aero injectors (brown) flowed 210cc....

cheap as chips on ebay, as the Saab tuners replace them with green giants or 630cc dekas.

T66 - 22/10/09 at 08:19 PM

took a while to find, this one is a carb R1

hobbsy - 22/10/09 at 10:13 PM

Took a while to find ?

Its the first hit when you google "turbo r1"

That site's been around for years - useful to know what power figures are attainable at what boost with what turbo etc. But as said its carbed so not much help WRT injectors...

JoaoCaldeira - 22/10/09 at 11:30 PM

Found this (untrusted) information:
Operating pressure is 42.6 psi with a max of 73.5 PSI

T66 - 23/10/09 at 02:06 AM

Originally posted by hobbsy
Took a while to find ?

Its the first hit when you google "turbo r1"

That site's been around for years - useful to know what power figures are attainable at what boost with what turbo etc. But as said its carbed so not much help WRT injectors...

It was recovered from my mess of "favourites", hence it took a while, then I realised it was a carby R1 and posted it anyway.

If that helps at all, should of goggled it....


JoaoCaldeira - 23/10/09 at 01:33 PM

Ok... some more info taken here...

they are

They also got some # on the side of the injectors , CDH210 .

Fuel pressure 284 kPa (2.84 kg/cm2, 40.4 psi)( fuel rail pressure )

Injectors resistace = 14.7 ohm .

Yamaha part# 5PW-13761-00-00

Dimensions here


hobbsy - 23/10/09 at 01:49 PM

Hmm, whacked "nippon injectors cdh" into google, check out the first few links, eg:

Points to CDH275's (allegedly 318cc/min - seems the 275 bit doesn't map directly to the flow rate but its probably proportional) here:,-OEM-Numbers/Detail

at 55USD each, there are also slightly cheaper places selling lots of different ones but they don't have CDH part numbers listed next to them (neither does that link above tbh - I'm sure they can be looked up but I'm at work at the mo!).

It looks like it might fit as this is the stock injector:

and this is the ~30% higher flow part:

Edited to say - clearly if you go this route to getting more fuel in you're going to need to cut back the fuelling by ~30% from idle up to where you start making more power than stock in the map.

Another edit to say its worth double checking that MD319792 part number does equate to CDH275 - that rswarrior website is a forum for the Yamaha Roadstar which makes a far chunk less power than an R1. Bit strange then that its got 30% bigger injectors but maybe they aren't using them at anywhere near 85% duty cycle. I thought it was always best to fit injectors that matched the max fuel requirement fairly closely so you get the best atomisation at lower fuel demand levels.

Its a starting point and as injector prices go generally seems cheap enough. Certainly as soon as they are labelled "uprated injectors" for an application the price seems to rise a lot!

[Edited on 23/10/09 by hobbsy]

JoaoCaldeira - 23/10/09 at 03:01 PM

How come I'm at work in Lisbon, Portugal, currently benchmarking an IBM machine in Monpellier, France, talking to a few locostbuilders in UK, and receiving information of injectors from US????


Never the less:

I have 3 injectors that will be a drop in replacement for the CDH210, they offer a higher flow. they are listed below. I sell any of the listed injectors for $34.99 each plus S&H

what size injector do you need?

the CDH210 flows 240cc/min

1. CDH240E......256cc/min
2. CDH275........284cc/min
3 HDB305F......308cc/min



How much boost do you plan to run?
How much cc will you need?

Did anyone used the stock injectros with low boost?


afj - 23/10/09 at 03:27 PM

it seems that most companys selling turbo kits for the 2002/3 r1 dont list different or addional injectors if your running 250bhp but the stage 2 kits offering 300bhp list up rated injectors

hobbsy - 23/10/09 at 03:27 PM

Nice find - Joao.

T'interweb is great isn't it

Are these injectors new or reconditioned as I see that site sells a lot of recon's.

Power wise if you assume the std ECU runs them at 85% duty cycle then and it makes say 150bhp (conservative) then just divide new size by old size and multiple by the bhp.

So CDH275's = 284/240 * 150 = 177.5 (18% increase)

HDB305F (are these definitely the same impedance?) = 305/240 = 190bhp (27% increase).

You can also get more out of them by increasing the duty cycle (via a PowerCommander) or upping the base pressure via an adjustable fuel pressure regulator (or a combination or both). But both have limits (you don't want to run too close to 100% duty cycle nor too much pressure on the injectors).

I seem to remember someone (with some amount of turbo'ing experience) complaining that the injected R1's (or 5PW at least) were a pain to turbo charge as the injectors were too small. It seems we may have found part of the solution...

To give some car related figures for reference my 200SX SR20 had 370cc injectors as standard (and makes 200bhp as standard - this can be upped to probably 300bhp ish on standard injectors). I changed them for 480cc injectors (from memory) from the S15 (JDM only) and ran ~370bhp.

I only intend to run enough boost to get a decent increase in power and not require uprated internals.

I'd be happy with anywhere from 220 to 250bhp. Looking at and other peoples experiences I'm hoping this is achievable with just a compression drop (two headgaskets or a single thicker one) and 10psi or less. Hopefully 7 or so.

I do have the option of ignition timing control with my earlier (but better out of the box) PC3R - this may help ward off detonation when on boost etc.

I spoke to someone recently how suggested that a compression drop may not be necessary if keeping the boost low and retarding the ignition on boost. I wonder how that would pan out. Would be ideal as means its a completely stock engine with just bolt on turbo and bigger injectors with a PC3R...

Did consider an aftermarket ECU for more control (but now I'm going waaaay off topic)

JoaoCaldeira - 23/10/09 at 03:56 PM

Hi all

They don't state new injectors, but include a new fuel pump and regulator... probably they are raising pressure instead of using new injectors.

As I already have a PCIIIUSB, and as I was thinking about just 5 -7 psi, I thought that current injectors could do, but I'd rather stay on the safe side. At the dollar value, it will be quite inexpensive to buy 4 injectors.
I'm going to the Commet gasket or 2 gaskets to drop compression.
I won't change any engine internals.

As I have the turbo, the main components required are just intercooler and manifold.
I intend to build my own manifold, though that idea may (really) drpo into pieces...


JoaoCaldeira - 23/10/09 at 06:51 PM

The question was:

The engine currently does around 150 hp, and we are aiming to 200 - 220 hp, so I think the correct ones would be the HDB305F.
These are prices for reconditioned ones, right?

And the answer was:

yes this price is for 1 Reconditioned Injector. new filters, orings, and grommets are included with the injector


It looks like prety good value to me.

One thing that remains to be checked is if the fuel circuit is able to feed these injectors...


hobbsy - 23/10/09 at 11:08 PM

I think the fuel circuit will be man enough (in terms of the rail and lines) for sure.

Whats probably worth doing is if you're using the standard R1 pump replacing it with an uprated item. Walbro do a cheap inline jobbie thats about the same size but will *definitely* flow enough fuel. All its got to do it keep the rail at the desired pressure - any extra goes back down the return line. From memory I went for a 180litre per hour version (the 255litre per hour ones are just overkill as they'll do enough fuel for 500bhp!).

Its tricky whether to know if you could just get away with more pressure and save the expense of the injectors.

I'm away from home so I don't know what the standard fuel pressure is, an adjustable FPR that raises the pressure with boost may still be a good idea as it will follow the boost level. The standard FPR only ever sees a vacuum or an equal pressure (or atmosphere). Will it raise the pressure if it sees boost?

JoaoCaldeira - 24/10/09 at 08:20 AM

I'm using a Bosh fuel pump...
I''m going to the garage to look better at the stock furl regulator, but I'm not hopping it having any adjustment / beeing able to deal with boost.

stock pressure is 40 psi, IIRC.

I don't understant the need of a raising fuel pump, due to the fact that the injection map is already changed via PCIII


afj - 24/10/09 at 08:25 AM

the standard r1 fpr is not rising rate so it just maintains 46ish psi all the time nomatter what rpm/speed/boost, im think all you have to do is fit a rising rate fpr AFTER the standard one, then when the std one blows and the fuel heads back to the tank its stoped by the rising rate one which will be set for 46ish psi off boost rising to 60ish psi on boost, then just map the powercommander to suit.
is this correct? can someone correct me if im wrong?
anyway 12psi boost is going to be 250hp at the flywheel so 6psi im guessing will be close to 200 210hp at the fly??

joao im guessing you need the rising rate as the injecters are not quite man enough at 40psi even with the pc111

[Edited on 24/10/09 by afj]

hobbsy - 24/10/09 at 02:53 PM

afj - I think you're confused about what I rising rate regulator is.

I thought all FPR's take a feed from the throttle bodies / plenum (which could be vac or boost) and alter the fuel pressure from the "baseline" pressure set at idle.

What happens with an FPR in forced induction applications is that it raises the fuel pressure by the same amount as the boost it sees from its feed from the plenum. So if std fuel pressure is 40psi and you're running 10psi of boost (pressure over atmospheric) then you'll get 50psi. This is a 1:1 *rate* FPR. (I might be off on the numbers but its the rate theory I'm trying to explain!)

What you also get (often marketed as "power boost valves" is *rising* rate FPR's, the FSE ones are often 1:1.7 (i.e. they raise the fuel pressure at a higher rate than the boost seen). Eg if the boost is 10psi they will raise the fuel pressure by 17psi not 10.

So depending on what you're trying to achieve a rising rate might suit things better (especially if you're running out of duty cycle adjustment in the ECU/PowerCommander).

However clearly it throws the fuel map out quite nicely if you decide to change between the two.

Also I don't think the setup you described would work. You only ever need one FPR (unless you've got two rails or similar!)

The first FPR would restrict the ability of the second one if it was trying to supply a higher pressure etc.

You just whip the old one of the end of the rail and fit the new one. Often you get an adaptor which allows you to remote mount it. And you can even fit a little gauge quite cheaply so you can adjust the base pressure quickly without having to connect a big gauge.

afj - 24/10/09 at 03:28 PM

ah didnt realise the yamaha one comes of the rail, thought is was a one piece design thanks

JoaoCaldeira - 27/10/09 at 10:00 AM

highjaking my own thread... and what tube diameter will you run from turbo to manifold / intercooler?

Actually, I've been reading too much on detonation, so it will definetly have an intercooler...


hobbsy - 28/10/09 at 01:36 PM

I haven't really got to the stage where I am determining pipework sizes etc.

I've got a good book at home (Forced Induction by A G Bell) which I'm sure has some guidelines for induction pipework and exhausts vs expected power.

I too would be running some kind of intercooler but due to packaging constraints I may go for a chargecooler instead.

I'm still at the gathering parts stage - I'm not in a major rush to turbo it just yet. Doing some weight saving / better brakes / suspension setup and more practice driving the thing first More power will come last.

JoaoCaldeira - 28/10/09 at 02:49 PM

Yeap... not in a hurry too.
It will be 2010 Winter project...
For now I'm just getting used after the crash rebuild.
I've got to have a good book on forced induction. How do you rate that book?


cossiebri - 28/10/09 at 08:29 PM

I've got a R1 turbo (4xv-carb'd) that now has gsxr1000 throttle bodies on it (very tight fit so should have no probs with them blowing off)have been told the injectors are large enough with a 1.1 fpr. Running stand alone ecu (kms) for the fueling and ign.Using a cosworth fuel pump (will prob replace with a new one as don't know age) for the intercooler was using a rs turbo one as they are a perfect size but now got a pace custom made jobbie, using 50 mm boost pipes also using a boost controller from a vw as it's got a stepper motor for more control(?)should be running around 15 psi but it's capable of 30+ already running JE low comp pistons and carrillo rods so should be strong enough! Not running yet but VERY close (funds permitting of course)Then just got to find the 400 odd quid to get it all mapped, hoping for around 280 bhp
But if not just whack up the boost
in hindsight should have just gone zx12/hayabusa would have been cheaper!

hobbsy - 28/10/09 at 11:57 PM

Yeah but when you're done your engine package incl turbo will weigh less than a zx12 or busa (remember the dry sump etc) and will make more power and a LOT more torque. Plus its more unique! God knows whats happened to my formmating on this posot

hobbsy - 1/7/10 at 03:10 PM

Sorry to resurrect an old thread but I've finally just ordered a set of HBD305F's (~320cc/min).

I'm starting to collect the misses pieces to my turbo kit.

Just wondering if the PC3R I have will give me enough control on the fuelling (and ignition!)

Joao - did you order any injectors? How are you getting on?

INDY BIRD - 1/7/10 at 09:28 PM

std injectors should be fine for 6 psi prob safe upto 8-10 psi,

run a begi rising rate fuel press reg and piggy back power comander,

prob only get away with 6 psi on std rods pistons long term any way?

if run a intercooler i ran 2" pipe to intercooler 6 psi may not even need it?

i got 260+ bhp on my zx10r turbo @ 8psi,

but had falicon rods and forged pistons in there and ran a 4x4 cossie intercooler modified, all was pretty safe at afr 11-11.5 good luck with the boost


hobbsy - 2/7/10 at 07:15 AM

At lot of the stuff I've read seems to imply that the 5PW injectors are already quite small for the task. I did rig up datalogging on duty cycle on my engine but I had gearbox issues before I actually logged any data (doh!).

For some reason I'd rather fit larger injectors than a rising rate FPR as I at least know the effect will be pretty much linear across the map.

I.e. I can take my existing NA map and in theory apply a correction factor of (old injector size / new injector size) to each of the cells and it will put the fuelling back to where it was before but then I'll have more "headroom" for the parts of the map where boost is made.

That's the theory anyway!

Its still not a whopping jump as the HDB305F's are only 320cc/min and the std ones are 240cc/min so call the NA engine 160bhp that means at the same duty cycle they are good for 320/240 = 1.3333 x 160 = 213.3 bhp.

Which isn't a millon miles away from my initial target I suppose.

They still seem like small injectors when compared to a std turbo car as I've said before (e.g. S14a 200sx runs 370cc/min injectors to make 200bhp as std).

Edited to say I have got some H beam rods from maximill666 so I will throw those in. I believe those are the first component you need to uprate on the R1. I could be tempted to put pistons in as well but before you know if you've spent a lot.

My original plan was just a stock engine with a thicker head gasket.

I think I'll run an intercooler (or charge cooler for easier packaging and shorter intake pipe runs) in any case as even at low boost they help look after the engine and make more power.

[Edited on 2/7/10 by hobbsy]

matt_gsxr - 2/7/10 at 09:02 PM

zx10r injectors are massive show-head designs and flow about 1.5x what gsxr1000 injectors flow (milk-bottle and stop-watch testing).

On my normally aspirated gsxr1100 I have maxed out the gsxr1000 injectors at 13=AFR (these are rated at 270cc/min* and are common to gsxr600 and gsxr1300) so I think that I wouldn't trust them with a turbo on an R1.

Lots of useful injector information and calculators here

Once you have got past the cheeky pictures.


*many think these are 240cc/min, my milk bottle wasn't precise enough to determine the difference between 270 and 240.

[Edited on 2/7/10 by matt_gsxr]

hobbsy - 14/7/10 at 01:20 AM

As a follow on to turbo R1 fuelling my main current concern is that using my PowerCommander PC3R (older serial version than the USB one but does ignition control as standard) will only allow be to map against TPS and not MAP.

I suppose if I were to use a BEGI rising rate FPR that might mean the fuelling is related to boost as this FPR is boost referenced.

I guess the "proper" but more expensive and time consuming way is a standalone ECU that uses a MAP sensor.

Anyone who has built an injected turbo BEC care to comment?

INDY BIRD - what did you fuelling correction figures look like in your PowerCommander? As I understand it the BEGI FPR lets you change both when it becomes rising rate and also the ratio (and the standard pressure)?

hobbsy - 14/7/10 at 02:46 AM

Hmm, just had another thought. I've got a megasquirt kicking around in the garage but don't quite fancy using it to run everything.

How using this in a limited fashion just to control a secondary set of injectors in the plenum runners or similar that only kick in when I am making boost (or just before)?

It would mean the off boost running of the car was still off the stock ECU (and PowerCommander) then when on boost it can whack the extra fuel in using a MAP sensor to know whats going on.

I can keep the original clocks (and very useful error codes) etc etc unlike if I go for a standalone. Also it *should* be simpler to map, no cold start etc etc just do the on boost bits.

I've already got a juicy enough Walbro pump to feed both sets of injectors.


[Edited on 14/7/10 by hobbsy]

matt_gsxr - 14/7/10 at 10:12 AM

I think the "piggy back" MS is an interesting idea. Would you run Alpha-N or MAP? You need both. This is possible with MS1 but is a bit messy to do.

The only problem is that the day your MS fails, is the day that you blow up your engine, as you get no warning at the low RPM sites (like you would normally if running an MS for everything).

I have some cbr600rr secondary injectors with the fuel rail and all the bits. These are nice as they direct air right into the trumpets. If you are interested. Like the ones in this air box mock-up.

Staged injection like this is great in a turbo as it takes some heat out of the mixture.

From what I have read, in turbo applications you want to be running lower AFR than NA. So you will want to have a bit more fuel than your simple flow-rate proportional to BHP calculation.


hobbsy - 14/7/10 at 01:52 PM

I think the MS I have is a V2 but I need to check.

I've not read up properly on the MS but surely I want to use just speed-density (using a MAP sensor, RPM and an intake temp sensor) for the secondary injectors.

I'm going to leave the primary injectors to the stock ECU (and existing power commander) I think.

Are you running secondary injectors on your NA GSXR1100?

If those secondaries are from a 600 aren't they going to be very small (for my application at least!)

Take your point WRT injector sizing but my initial thought on the secondaries was maybe to use the rail and injectors from a spare set of R1 TB's that I have lying around.

I seem to recall some issues with their impedance when used with megasquirt? Will need to do more research.

After doing more research last night I came across a US site (predominately turbo busa's I think) and it seems what they deem as stage 2 onwards is all about running secondary injectors controller by either MS or Microtech. Stage 1 is the only one that does it the slightly dirty way of using an "FMU" (rising rate adjustable FPR).

hobbsy - 14/7/10 at 02:51 PM

Originally posted by matt_gsxr
The only problem is that the day your MS fails, is the day that you blow up your engine, as you get no warning at the low RPM sites (like you would normally if running an MS for everything).

Just re-read your post and this bit concerns me a bit! I wonder if there is anything I can do to counter this? Having a quick think about it I don't know that there is...

Hmm. No-one said it was going to be easy (or maybe I did? )

johnny chimpo - 11/6/13 at 12:36 PM

dragging up a mega old thread.....

Hobbsy, did you ever get your turbo'd r1 finished?