T J Fuel Injection

[graham.codling]

Thank god mines running (on westlake cylinder head ) certainly stops me feeling pissed off ( enough parts to build another 4 )

[251 ENG]

What size throttle bodies are suitable for TJ on a mini ?

[graham.codling]

I've seen 36/38 mm throttle bodies .mine are 45 mm .

[App K]

Mine are 38mm on the inlet manifold side of the throttle bodies (45mm at the trumpet end). The inlet manifold is then reduced down to 30mm to match up to the Arden Head.

I have a few sets of these and they are TJ throttle bodies part number 10228/1-3.

[Astro]

When I planned my 8 port I heard a lot of terrible things about these tecalemit jacksons and therefore decided to use 40mm webers. Was it a fault?

[John Bull]

When I planned my 8 port I heard a lot of terrible things about these tecalemit jacksons and therefore decided to use 40mm webers. Was it a fault?

It's actually a very simple and basic system, but certainly for a competition car, it does the job well. I'm finally starting to understand mine, and it's getting better every day.

[Astro]

Thank you. Seems to be more interesting than I thought. My engine is only used for the French historic hillclimb championship and I am just learning to handle the Arden together with the Webers.

[Pete]

Trevor, found an Autosport report from the first round of the '68 ETCC which suggested KDK used Lucas injection, I'll scan what I find and let you have them as I find 'em if you've not already got them. Maybe they switched about.

[Astro]

Thank you! When the works cars changed to the 1275GT they also changed from Lucas to Weber. Why?

[trevorhp]

Hi Pete,
It would be nice to see that Thanks

I have another report from a programme from a later ETCC Round, it says that the Vita minis were 970cc and ran on Lucas injection even though the picture attached is clearly the TJ setup.
Later on in a set of results from Brno it lists the Vita cars as 1275cc engines and the winning car as being driven by Alec Poole!! although the points went correctly awarded to John Handley.

I guess in the era before digital cameras, mobile phones and PC's it would be easy to be mis-reported or lost in translation.
Will Dick is adamant that the cars had TJ setups in '68 and still in '69 when he worked on KDK for Barrie. He also confirmed along with Barrie that Vita never ran the 5 speed Colotti boxes in the races, they always broke in practice

Several people have indicated that the Lucas setup was prohibitively expensive back then except for very few F1 teams

Vita were agents for TJ but you never know.

More contemporary under bonnet pictures would help but after many years of asking and searching I don't have much at all
They must be out there, but probably somewhere in the rest of Europe!!
So the search is on guys.

[John Bull]

Did a bit of experimentation over the weekend. I fitted a set of short trumpets, which allowed the standard bonnet to close, with between 1 and 2 inches between trumpets and bonnet.

It felt rich right away and eventually wet a couple of plugs, so back to fibreglass bonnet with gaping hole exposing longer trumpets.

Took it for a long run today. Oil press and temp OK, fuel pressure 30 at 2000, going up to over 50 at 6000. AFR between 12.5 and 13.5 virtually throughout the rev range, however if I floor it from say 4000, it goes flat. Feed the throttle in progressively and it revs well up past 7000.

Anybody got any idea how to cure it? I'm running out of time - next race meeting in Italy in early June.

[Astro]

with group 2 and even group 5 we need a standard bonnet. This is one way to calm down the flow. The other way are those long bended trumpets

[Pete]

More contemporary under bonnet pictures would help but after many years of asking and searching I don't have much at all
They must be out there, but probably somewhere in the rest of Europe!!
So the search is on guys.

Yes it is odd, I've detail under bonnet shots of Arden, early and late CCC and Abingdon 8 port racers but never found the equivalent Vita pics, probably because they only ran for a year and mainly abroad. Have you tried McKlein, they do have a lot of European stuff...

http://www.mcklein-imagedatabase.com/

I'll ask a couple of contacts close to the team just in case they have any pictures I've not seen. You never know ? I've asked Maureen Magee aswell because I'm sure she photographed Croft and Snetterton in '68.

[graham.codling]

John have you tried slackening the fuel metering unit cable off a touch?

[John Bull]

John have you tried slackening the fuel metering unit cable off a touch?

Seriously thinking metering unit in fact. Could be that the valve is either not opening enough, or starting to close again at full throttle. I'll check it out Monday, as off to Sicily this weekend on my 1934 Triumph motorcycle for a Vintage bike rally.

[graham.codling]

You can adjust the flow at inlet side of metering unit .if you think it's closing at full throttle its poss it's been adjusted at some time .it works very similar to a Reece fish carb .enjoy your weekend John I will be cutting the lawn at the weekend.

[Astro]

If it the metering unit, why does it change with changing the inlet? Ignition time is OK? Here is annother lawn to cut

[graham.codling]

The inlet of fuel flow on the metering unit astro .now you can cut the hedge as well as the lawn this weekend .

[John Bull]

PROGRESS REPORT.

As things stand, if I get it right at low revs - idling well at 1500rpm, it's weak at anything above 4500rpm. If I get it right (say 12.8 AFR) at 7000rpm, then it's terribly rich below 3000. Anyone got any suggestions, please.

Basically there are 4 main variables.
1) Slide opening in relation to fuel opening at control unit.
2) Control unit fuel valve. This works like a bathroom tap. I have set the control unit so that air just flows through the valve when fully closed.
3) Fuel pressure valve on return. Tightening the spring builds up more pressure - presently 25psi with electric HP pump on - this also makes mixture richer. Anything below 20psi the engine will tick over nicely but won't rev.
4) Slow running pressure valve on distributor unit. The setting of this is extremely critical. Tightening it gives you a good idle, but will not produce a supply of fuel for starting, with just the pump on.

Incidentally I have a selection of fuel cams, and have just filed a bit more off the idling side of the cam to make it leaner at the bottom end, but this still does not seem to be enough.

Any help, much appreciated.

[Astro]

hi,

did you try it on a rolling road or on a real one? on a real one it might be the additional pressure of the air coming in. Than try to change the gap between bonnet and body. If there is a reponse, you have the problem. If not it's still the setup.

Best