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Dutatec injectors on throttle bodys
ceebmoj - 7/1/14 at 10:58 PM

I have been looking at a number of throttle body setups for the Duratec. and they seem to that seam to have the TBs drilled to take injectors as well as the direct to head injectors in the Duratec. So where is the best location for the injectors in the head or out by the TB? or do people run 2 sets of 4 injectors?


http://www.raceline.co.uk/products/part_section.asp?SectionID=13&CategoryID=1

edthedrummer - 7/1/14 at 11:04 PM

the standard duratec has the injectors in the head, aftermarket throttle body set ups usually mount the injectors in the throttle bodies and come with blanking plugs for the head mounted injector ports.

I would guess that the injectors mounted in the throttle bodies are the way foward, considering most throttle body kits, designed to release more power, have them mounted there. Look at SBDevelopments very own Taper throttle kits for example, which has had countless hours and money spent developing it, the fuel rail mounts underneath, near the actual butterfly.

peter030371 - 8/1/14 at 08:50 AM

I had the same question recently.

Omex have told me that they find injectors in the TB more 'reliable' than head mounted. I am off to Autosport tomorrow to see them and getting more details on this is one of my questions to ask

This is also an interesting read linky

The angle and position of the injectors on my GSXR TB looks very similar to the SBD setup so I am going to try and get as close to this as I can Info sheet

MikeRJ - 8/1/14 at 06:44 PM

In general you want the injector as close to the valve as possible for the best emissions performance, and as far away as possible for best power. This is why the injectors are mounted outside the throttle body, spraying into the ends of the trumpets on high performance applications (e.g. some modern superbikes, formula 1 engines etc.).

Mr C - 8/1/14 at 07:10 PM

I've also been looking for TB's for a Duratec, so am particulary interested in this discussion. I understand that longer trumpets also increase power particulary torque. For installation reasons (space) I'm favouring the DTH bodies from raceline, be interested to see what you go for.

edthedrummer - 8/1/14 at 07:18 PM

A downside to mounting the injectors further away from the valves is the time taken to re-establish the mixture upon application of the throttle, presuming deceleration fuel is turned off. Whilst this takes only a moment, it can provide a small noticeable hesitation when you get back on the gas. It's fairly simple to get around this however, by only cutting fuel for a small section of the rpm whilst off throttle, and re instating it before you actually accelerate. All this is map work though.

Also, on a side note... If the injectors aren't in the head, and are at the end of the throttles, don't use a fuel cut as a limiter... You will hit the limiter, the injectors will turn off, but the fuel mixture remaining inside your throttle bodies will still enter the chamber as normal and the revs will still rise, perhaps only, but back in the day, when fuel injection trickery was new to Motorsport, there was a fair few blown engines on the start line at one event...

edthedrummer - 8/1/14 at 10:05 PM

quote:
Originally posted by Mr C
I've also been looking for TB's for a Duratec, so am particulary interested in this discussion. I understand that longer trumpets also increase power particulary torque. For installation reasons (space) I'm favouring the DTH bodies from raceline, be interested to see what you go for.


Longer trumpets don't really increase power. Its a bit of a grey statement to be honest, and there is quite a lot of misunderstanding.

Both the inlet and exhaust length can be tuned to the engine, by shortening the inlet tract, the power curve is lifted upwards generally, but at the sacrifice of torque lower down. The opposite is true for lengthening the inlet, a long inlet tends to bring the power curve down at the top end, promoting a bit more torque lower down the rev range.

Ed.

ceebmoj - 8/1/14 at 10:22 PM

Thanks for all the information guys does any body know how much the SBD throttle body kit for the duratec is? I suspect I cant afford it by a long shot but would be interested to know.

[Edited on 8/1/14 by ceebmoj]

edthedrummer - 8/1/14 at 10:25 PM

I think the taper throttle bodies themselves are £1300 ish for just the inlet, if you want the loom, injectors, ecu and inlet kit then its about £3k.

Mr C - 9/1/14 at 03:21 AM

Advanced Automotive do a Jenvey/Omex kit for just under £2k, (straight not tapered) I'll probably go for the raceline bodies, emerald ecu from retroford and wiring loom from emerald themselves, works out a tad cheaper and the loom is literally plug and play. Not sure about an airbox as I'm doing a mid engined install and access/room is tight.