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Location:
Melbourne, Australia
Registered:
March 2005
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2T-G 1940CC: carbs/injection/quad throttle...?
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Sun, 17 April 2005 09:23
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Hi,
I'm in the process of prepping a 1940CC bottom end for my 2T-G. Interested to hear your thoughts on an appropriate fuel delivery system.
If you're running at 1770 or more, what is your spec and what did you use? Feedback on your setup?
1. Existing 40mm Solex carburettors
Pro:
I've got some
Con:
Restrictive given new capacity
Require rejetting to suit new displacement
etc. etc.
2. OEM 2T-G EFI
Pro:
Bolt on manifold with injector hardware and throttle, etc.
Advantage of electronic fuel injection over puddle-dumpers
Not too expensive
Con:
Requires aftermarket managemnet for my application
No individual throttles
Designed for econobox stock 1588CC, may be restrictive (or at least suboptimal??)
3. DCOE ITB kit ie. Injection Perfection, EFI hardware, etc
Pro:
Programable managment allows ease of retuning
Can be built to spec (throat size, etc.)
Direct fit to existing manifold
Con:
Bloody expensive
Requires aftermarket management (also bloody expensive)
4. Adapt 20V throttles
Pro:
Not as expensive as aftermarket throttles to buy
Con:
Need to build adaptor plate or adaptor manifold to 2T-G (possibly cut and shut 2T-G manifold to 20V manifold? if port spacing is similar)
Requires aftermarket management
5. 44 Solex or 45DCOE carburettors
Pro:
Direct fit to existing manifold
No need to add additional parts to drive EMS
Sufficient throat size to suit application when choked appropriately.
Con:
Difficult to find both carbs and parts (jets, chokes etc.)
Difficult to find a tuner equipped to set them up for the applciation.
Thanks in advance for your consideration. I'll keep thinking and start researching more.
[Updated on: Wed, 16 November 2005 00:25]
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I supported Toymods
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I renounced punctuation
Registered:
May 2002
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Sun, 17 April 2005 09:29
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ITBs.
Lock thread.
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Location:
Melbourne, Australia
Registered:
March 2005
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Sun, 17 April 2005 11:21
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OK. Sounds like the motor you plan to build is the full bottle.
Getting Solex carb bits is a bitch so scrap them as an alternative.
Seems like by the options you have provided, if you go any EFI option, you'll be buying a standalone ECU. By the time you buy Webers and get them tuned, you'll be well on the way to having purchased a set of ITBs, a standalone ECU AND having them tuned. Don't believe me? Price it out. Of course, your computer tune won't go out of tune and you get EFI reliability all day.
The expense is justified so the choice is simple.
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Sun, 17 April 2005 16:52
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Fair point, and I do agree.
With consideration given to the cost-efficient manner in which this build had been undertaken thus far, use of good second-hand Weber or Solex carburettors would be acceptable, but for lack of availability. I wouldn't stretch the cost to new (presently unavailable anyway) carburettors, which i agree are hideously expensive.
I've choked at some of the costings for new DCOE pattern throttles from Aus (EFI Hardware, etc.), US (TWM) and UK (Alpha) sources, but I'll go that way if need be.
I'd be interested to hear from anyone who has had success retrofiting 20V throttles using an adaptor plate or such. Presently following up on some leads uncovered with the erratic Toymods search; will see how I go.
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Mon, 18 April 2005 05:23
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Another option may be to use throttle blocks like those you can get from Meridian Motorsport (sort of Moorabinish).
May be possible to make them with a single throttle shaft and with the correct bore separation (would save on linkages).
I have no idea regarding the price - best to chat to Toby Hunt there.
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Mon, 18 April 2005 06:17
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Cheers for the info.
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Club President
I supported Toymods
Location:
Sydney
Registered:
May 2002
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Tue, 19 April 2005 13:37
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Septembersqual,
Of the 5 options you list, Options 3 and 5 are really the only Ones worth considering.
Option 1 is too restrictive for an engine your size.
Option 2 is also a restriction for your engine (As tested by Sean Malony and advise to me in the early 90's by Sean himself)
Also supported by my own flow bench reserch.
Option 4 Is a compromise ITB set up at best and will require allot of fabrication to be neat and possibly plenum work to fit neatly. Most likely not as cheap an option as first thought and easily as expensive as option 5. Will stil require aftermarket ECU so most likely more expensive than option 3 as well !
Option 5 - Will sound awesome and deliver great flat out performance with compromised fuel economy and tune level.
Option 3 - Well covered by GT and the answer you are looking for.
Ask yourself this question.... Having spent the greenback on a tough engine will you really be happy retarding its performance by compromising on the one thing that will define the end result in both power and drivability. And if you do compromise will you ever stop wondering just how much better it really should have been !
Just go with Option 3 !
Thats My 2C anyway
PS good to see your behaving yourself these days 
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Location:
Melbourne, Australia
Registered:
March 2005
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Location:
ipswich queensland
Registered:
April 2004
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Tue, 19 April 2005 22:06
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ok now i might have missed the hole idea behind this but wat is the possiblity of just using a intake setup from a 2 litre enigne, like say an 18rg?? it just seams to me that if u have a 2 litre enigne u put stuff from a 2 litre to fuel it properly.
sorry if i am totally rong but im lost and i thought i might atleast try to help
good luck
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I supported Toymods
Location:
I renounced punctuation
Registered:
May 2002
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Tue, 19 April 2005 22:56
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And lose all that fat midrange and instant throttle response that's there for the taking with well setup ITBs?
I say ITBs or, if you have access to an excellent Weber tuner who is prepared to make no compromises, DCOEs (expect the wallet nerve to really sting however).
That said, knowing what human nature is like, changing a multitude of jets and emulsion tubes is a major pain in the ass, but sitting in a seat and tapping on a keyboard isn't so you're more likely to get a satisfactory outcome with the latter.
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Location:
Canberra
Registered:
May 2002
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 00:38
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Do 2TG's have the injector bosses mounted in the head like 4AG's?
If not and you go for 20v TB's, you'll also need to fit injector bosses and build a fuel rail.
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Location:
Adelaide
Registered:
May 2003
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 00:45
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Either that or do the "i love backfires" injection system, and inject straight down the throttle. Really sucks unless you are at a significantly open throttle for most of the time.
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 04:33
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| lilcrash wrote on Wed, 20 April 2005 08:06 |
ok now i might have missed the hole idea behind this but wat is the possiblity of just using a intake setup from a 2 litre enigne, like say an 18rg??
good luck
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Thanks for your input, unfortunately 18R-G hardware does not fit the flange pattern or port spacing of 2T-G.
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 04:35
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| gianttomato wrote on Wed, 20 April 2005 08:56 |
I say ITBs or, if you have access to an excellent Weber tuner who is prepared to make no compromises, DCOEs (expect the wallet nerve to really sting however).
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I agree, and will go further to say that the choice may be dependent on what I can find in the way of DCOE's or 44 Solexes second hand.
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Location:
Canberra
Registered:
January 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 05:27
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The one thing you didn't mention is if you are using a head with standard ports and cams. The limiting factor of a 2TG at this size is the ports and cams NOT the 40mm solexs. I can support this with personal experience and dyno sheets from three different 1940cc 2TGs.
One engine I built for myself ran a 1940cc bottom end, standard ports, 286deg Wade cams and 40mm solex carbs with 34mm chokes. This engine made 92kw at the wheels but wasn't at all happy trying to rev past 6500rpm. I then had the head ported and ran 36mm chokes( the limit for a 40mm carb). The engine produced 97kw atw and happily reved to 7000rpm.
My current engine is very similar but runs 45mm efi hardware throttles, a Haltech and 308deg cams. Its made a best of 104kw and is happy reving past 8000rpm.
The point I suppose is if you are doing it on a budget then theres nothing wrong with using the solexs. I think the argument of parts availability is crap. Sure parts are almost impossible to find but who says you need them. My 36mm chokes were machined out from 34mm chokes. You don't need to change emulsion tubes and the like and as far as jets and air correctors go carefully soldering them and redrilling with jet drills is not difficult and very effective. you should only have to drill them out though cause you'll need to go bigger. Idle jets can also be drilled out to suit. Having done exactly this to two engines they were both very driveable and behaved as they should and performed very well.
Geoff
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 06:06
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Thanks, interesting points. What kind of port work has been undertaken across the course of these builds? Still standard?
CelicaRA45 or whatever posted some flowbench before/after results on a range of 2T-G head castings, i seem to remember the flow increases were only about 5-10%. Is this level of improvement significant?
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Location:
Canberra
Registered:
January 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 07:24
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The first engine had standard ports origionally and then a ported head, as I said in the post. The following two engines were ported the same. They were done at Superflow in Sydney.
Geoff
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 12:33
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Okay, thanks. I see what you're saying now.
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Club President
I supported Toymods
Location:
Sydney
Registered:
May 2002
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 12:51
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Second hand Carbies are about but not as common as they used to be. I not long sold a pair of 42mm webbers that would have been great but they are in canberra now.
I'll be honest, If it was my engine it may well get Carbies, I LOVE the sound and have experienced what a no budget tune can yield. 3 Days and $900 later Tina's old 2TG purred like a Kitten at idle and was smooth and responsive past 8000rpm. I have never had a set of ITB's but i would expect them to sound similar to a set of side draft carbies in which case it really comes down to budget and what your starting with. I had the carbies and manifold etc already when I did Tina's. The tuning was done by Frank Kleinig motors in Girraween but I am led to beleive Frank may have retired at the end of last year. His son used to work with him so the art may not yet be lost completely.
As for 40mm Solex's, They are around if you look but I'd suggest they are really to small for a tuff 1940cc 2TG. Sure you can rejet them etc but your Jet/throat ratio will be less than ideal. A set of 44's off an 18R-G tho would suit the task 
Head porting is a art like much like tuning Carbies, Many people claim to have the answer, very few actually produce the goods. My current 2TG is turbo charged so the porting requirements are allot different to an N/A application. MY inlet flow improved by up to 30% depending at what lift values and my exhaust flow increased by up to 22%. Mind you there are 2TG heads with muchmore aggressive porting than that around.
What are you doing in the way of head and cam work ?
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Wed, 20 April 2005 14:39
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Regarding cams, I'd have thought that something in the vicinity of 304 deg would be manditory, maybe even 320? Will take further advice on that, but had planned to start at 304/304.
Still reading more in respect to head work. I've got a few passing understandings about concepts like valve unshrouding and so forth, but I'm very much 'consciously incompetent' about how it all should come together or what is necessary in any given application.
I'm having a crack at this as a first foray into building an engine, having fortunately aquired a number of suitable parts for very little cost. It's something I've wanted to do for a while but at 21 and first time around I'm still very much a learner.
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Location:
Melbourne, Australia
Registered:
March 2005
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Re: 2T-G 1940CC: carbs/injection/quad throttle...?
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Fri, 22 April 2005 14:50
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Okay, just got hands on some 44mm Mikuni-Solex carburettors; I'm feeling that at the price paid I'll come out significantly ahead with the carb induction cf. ITB's and aftermarket management.
Most of what I've read and heard recently suggested that a deburr of the casting should be adequate for the time being.
Any experience with cams to share?
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