I've just started looking at fitting a set of Triumph throttle bodies to my AJ-V6, and the good news appears to be that the Jag injectors fit:


The bad news is that a bit of googling shows that the code on them (XW4E-A5C) is for an injector which only flows 153cc/min... can this be right?!? The stock car is meant to have 240hp, and the injector calculators on Witch Hunter show it should be closer to 260cc/min...

Have I got some duff information, is the Jag seriously under fuelled, or is the calculator wrong? Or the bonus option, am I being a numpty and missing something obvious?

Answers please on the back of a postcard....

[Edited on 16/2/15 by Badger_McLetcher]

I could be wrong but figures probably for a 4 cylinder engine so multiply by 1.5 to get 6 cylinder that brings the figure close.
probably total rubish but I tried

Triumph TBs are too small for your engine.
We mapped a Cosworth 2.9 v6 the other day, six triumph bodies, slightly up on standard power but not much, looked to me the TBs where holding it back.

Your right, the Injectors are on small side. We found the same on this engine.

www.facebook.com/baileyperformance

[Edited on 16/2/15 by BaileyPerformance]

Interesting about the Cosworth v6 not making much over stock (190hp IIRC), these have been used on quite a few mazda 2.5 KLDE v6's and these make around 205hp from a smaller volume flow. Not sure if there is different throttle bodies in the triumph range but I have a set of 955i RS once and these are 42mm inlet/butterfly bore. According to the jevey website a 42mm throttle body on a v6 should be good for 300hp.


here's a link to the jenvey Jag v6 TBs - 45mm and there is a westie with this engine in running around 300hp, nice kit if you have the deep pockets - http://www.jenvey.co.uk/home/throttle-body-kits/jenvey-dynamics/jaguar-v6-sf45-throttle-body-kit-ckjr02

[Edited on 16/2/15 by Ugg10]

[Edited on 16/2/15 by Ugg10]

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Originally posted by Ugg10
Interesting about the Cosworth v6 not making much over stock (190hp IIRC), these have been used on quite a few mazda 2.5 KLDE v6's and these make around 205hp from a smaller volume flow. Not sure if there is different throttle bodies in the triumph range but I have a set of 955i RS once and these are 42mm inlet/butterfly bore. According to the jevey website a 42mm throttle body on a v6 should be good for 300hp.

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I think that is when they moved from the traditional looking separate tbs (look a bit like jenvey duiect to head ones) to the three joined together slimline ones with no injector port (injectirs were in the head I think). A quick eBay search for "triumph rs sprint throttle bodies" will show you both types.

If you want pictures and dimensions I have them on my anglia build blog, these are for a 2001 955i rs sprint - http://anglia1968.weebly.com/engine--gearbox.html

Worth also noting that the 3.2l vauxhall omega v6 injectors fit these tbs. You will need to make up a fuel rail or chop and sleeve the original.

Hmmm... may have done some duff research on the throttle bodies, I'll have to measure them when I get back on the weekend. The injectors still seem a bit small for the engine though!

The later Triumph bodies have a 46mm butterfly & air filter side diameter.

The head side is oval, 44 x 39mm.

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Originally posted by Badger_McLetcher
Hmmm... may have done some duff research on the throttle bodies, I'll have to measure them when I get back on the weekend. The injectors still seem a bit small for the engine though!

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Ah, thanks mate - those look like the buggers. I was going off the code on the side of them (can kind of see it here) though it appears that there's more than one code. Makes sense now!

As for the throttle bodies I'll have to double check, I've been going over the notes I made when I was doing the research and I think I got myself confused between the 42 and 46mm versions at some point. Unfortunately the sales have dropped off my Ebay so I can't check, and I'm not back around the workshop until Friday so I can't go out and double check!

I'm not sure what to do if they are the 42mm versions, as you say the Jenvey website show's that size as OK, but I'd imagine that's with the nicely flowing adapter manifold and stacks. They don't match up with the Jag ports exactly, but I think they're not too far off in area terms.

[Edited on 16/2/15 by Badger_McLetcher]

If you do a bit of searching on the net there is a build thread for a lotus esprit running thus engine, he eventually went for a mondeo st220 inlet as he had clearance issues.

http://www.thelotusforums.com/forums/topic/8126-30-v6-conversion/

I akso have a friend that is looking at this setup in his scimitar, if he comes up with anything I will let you know, he has requested an account on here, waiting for it to be validated.

The 46mm tbs are a totally different design to the ones in the picture in the first post. Those are like mine as far as I can tell.

Having looked at this, and if bonnet clearance is nit too much of an issue I woukd look into an exhaust manifold type connector with gsxr tbs and the jag injectors in their original position, something like this alfa v6 in a lotus europa (half way down the page)

http://www.alfagtv6.com/discus/messages/199/1988.html?1099096020


[Edited on 16/2/15 by Ugg10]

[Edited on 16/2/15 by Ugg10]

[Edited on 16/2/15 by Ugg10]

Aye, I saw that! Was one of the reasons I chose this engine in the end. However if I kind of want ITB's as this engine isn't the most responsive of lumps, especially since my cunning lightened flywheel plan fell through! If I end up having to go for one then I'll probably just fabricate up a system from scratch with a big single or duel smaller TB's.
I did look at Aprilia RSV throttle bodies but they were just too wide to fit three pairs on, also pretty large in bore!

And thanks for the help, it's appreciated!

[Edited on 16/2/15 by Badger_McLetcher]

How far off port matching are they? I use the same ITbs on my KLDE engine, but my 1/2" adaptor plate is enough to port match them fairly well. The only issue I have is the original injector recess in the heads could be with being welded/filled up to give me a really smooth shape. My adaptors didn't take all that long to make and only required my pillar drill, an M7 tap and a half round file. Oh and the usual amount of time, sweat, swearing etc!

It's also worth bearing in mind that a slightly undersized throttle body is better than an oversized one. The Jenvey figures, IIRC, are the point at which the throttle body present no restriction. Above those power levels, the engine will still work just fine as the small(er) size aids throttle response to the slight detriment of top end/all out power.

There two other version of the triumph ITBs as it goes, but only one set is respacable. They also have the bolt on mount on the upper side so they'd need a mounting rubber on the bottom.

They're not too far off port matching from my casual mock up on Sunday, the TB oval is a bit shorter but wider IIRC. I've got to use a 20mm or so adapter plate to clear some of the bits in between the cylinder heads and ensure clearance for the throttle bodies. I've got the aluminium on order, was planning on making them in the same manner as you I think.

[Edited on 16/2/15 by Badger_McLetcher]

With a 20mm plate you'll have loads of metal to re-shape the ports. Thankfully, mine weren't too far off and I can now see the inlet valves with the throttles open. Pointless, but cool!



If you're mostly keeping the oval shape, I can recommend using the nearest size hole saw you can get. I tried chain drilling the plates at an angle, and it was a waste of time. The hole saw did 80-90% of the work for me, just leaving the final shaping and smoothing to do by hand. The rest of the photos are here, if they'll be of help to you.

Awesome, thanks for that. I'm probably going to chain drill my exhaust flanges (304 stainless), but I've got a couple of hole saws that will hopefully be good for doing the inlet plates. It looks like I'm planning the same approach as you - get the core hole common to both drilled and then open it out with the die grinder... that's the plan at any rate!

Nice work

Back to the original question, as the original injectors were sized to the engine they will have some additional headroom so should be perfect.

My car runs 100% opening at WOT, it's not an issue and only is required for short bursts, using an adjustable fuel regulator you can always Jack up the pressure slightly if it's an issue.

Get it running, log it then decide is my advice.

Can't assume that mark. I am aware of at least on car that has injectors at 100% duty from the factory!

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Originally posted by Badger_McLetcher
I'm probably going to chain drill my exhaust flanges (304 stainless)

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Aye, funnily enough I was tempted by the same route! However part of doing this build is to try to teach myself how to do stuff, so I figure I may as well start from scratch and get the experience. Also I wasn't entirely certain they'd clear my steering shaft, so that helped tip it.

As for the injectors, I'm thinking they must be the 260cc/min versions - that lines up well with the power rating. That means upping the duty ratio and maybe the fuel pressure to 4 bar should give me enough head room to get going with at least.

[Edited on 17/2/15 by Badger_McLetcher]

I'm hoping the same is true for the Triumph injectors. If not, there are shorter pico style ones that fit, should any airbox need a little extra space.

You could always run the injectors in the original position and a second set in the tbs - just a (slightly deranged) thought.

I'll have to look at the original Triumph injectors, but thinking about it I reckon they put out around 270cc/min, so may end up sticking with those in the end! They are a fair bit bulkier than the Jag items though.
Two injectors is not a daft idea, I think it's meant to keep the low end throttle response a bit better. Saying that, it means 2x fuel rails, 2x injector looms and being more difficult to map. We'll see how it goes I guess!

I considered it for a while, but trying to run my V6 in full sequential mode I figured was enough of a challenge for now! I think for the power levels we're talking about it's just extra work for very little gain, if any real world gain at all.

So the big question is what did you do?

Did use the Triumph ITB's?

Or something else??

I ended up using GSXR 1300 throttle bodies, mounted on a homemade manifold and modified to accept Z20LET injectors fed by a custom fuel rail

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Originally posted by Badger_McLetcher
I ended up using GSXR 1300 throttle bodies, mounted on a homemade manifold and modified to accept Z20LET injectors fed by a custom fuel rail

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Haha I realised I while back that I never seem to make life easy for myself

Any pics of your progress on this available?

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Originally posted by CosKev3
Any pics of your progress on this available?

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Am I wrong in thinking that some injection systems injected on the non fire stroke into the inlet side and then just before bang injected a second time before the fire, hence smaller injectors could be used. A bit like the spark plugs fire on two out of four cylinders at a the same time, but it makes no difference as one cylinder is exhausting as it happens.

I think it's in the four stroke performance tuning book.

I guess it depends on the ECU in use.

Adrian

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Originally posted by AdrianH
Am I wrong in thinking that some injection systems injected on the non fire stroke into the inlet side and then just before bang injected a second time before the fire, hence smaller injectors could be used. A bit like the spark plugs fire on two out of four cylinders at a the same time, but it makes no difference as one cylinder is exhausting as it happens.

I think it's in the four stroke performance tuning book.

I guess it depends on the ECU in use.

Adrian

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Originally posted by 40inches

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Originally posted by CosKev3
Any pics of your progress on this available?

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Bottom of this thread Kev
https://www.locostbuilders.co.uk/viewthread.php?tid=198643

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