Megatron-UK
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| posted on 31/3/06 at 07:27 PM |
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Pinto - ditching DCOE's ?
Hey folks... normally a lurker here, but we're finally getting to the point where the car is nearly finished (only been building it since
1999!!!  )... and now we're finding that the twin 40's that we have are, frankly rubbish.
I wish we'd started with another engine - the 20XE, in particular (theres one in the car on my avatar pic...), but, we've invested too
much money in the engine to dump it now:
Ported injection 2.0 head
-1.5mm planed to riase CR to approx 10.5:1
Thinner head gasket
New stainless injection valves
Lumpy cam (fr33 or 32 ISTR)
205 injection block
+1.5mm overbore
+1.5mm pistons (2063cc)
Reground and polished crank
1600 flywheel (approx 2/3 weight of the 2000 flywheel)
4-2-1 manifold
An obscene amount of money at the time, and something we'll never get back if we were to sell it on.
Sooo... I'm wondering what to do about the carbs - there's no way I can afford a brand new set of 40's or 45's. So, the
questions I need to answer are:
1. Is it worth sending the carbs anywhere to get them checked over? The insides are all new and jetted up correctly for the capacity / rev limits, but
the carbs themselves are probably on the order of 25-30 years old 
2. Are there any alternatives to DCOE's or DHLA's that sound as good and give as much punch?
3. How easy would it be to convert the Pinto to throttle bodies? ... either using the DCOE bodies, or with motorbike carbs? Does anyone have a
detailed part listing or guide?
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Kissy
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| posted on 31/3/06 at 07:39 PM |
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Easy answer (and first response) is either get them checked out/overhauled, or do it yourself (Haynes do a Weber manual).
Gut feel says tidy 'em up, stick 'em on eBay and go "bike tb's and Megasquirt'n'spark" route. Think
you'll be surprised what twin 40s/45s go for now.
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britishtrident
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| posted on 31/3/06 at 07:45 PM |
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Check the cold start valves on the carbs are free and seating --- the choke tends no to get used on the these carbs as people tend to pump the
throttle a couple of times instead. As a result the cold start mech can stick slightly on.
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Megatron-UK
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| posted on 31/3/06 at 07:46 PM |
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Thanks for the reply... I've been looking at second hand sidedraughts on Ebay for the past few weeks and they're silly money - getting on
for £200 for a set of 40's in reasonable condition... even downright filthy examples can get £100 or so 
I may just cut our losses with these. We've already overhauled them, had them apart and replaced all the seals etc.. I think they've just
had it. It just won't run right - the Dellortos on the Escort were much, much nicer.
Got any further details on what bits are needed to go the TB route? My limited diy injection knowlege says:
- bike tb's and fuel rail / or converted carbs and injectors fitted to inlet manifold
- some kind of throttle position sensor
- fuel return line to the tank/swirl pot
- megasquirt/spark (much advantage over using a distributor??) ecu
The engine is currently running with the sierra bosch ignition module and disributor.
[Edited on 31/3/06 by Megatron-UK]
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MikeRJ
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| posted on 31/3/06 at 08:13 PM |
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quote:
Originally posted by Megatron-UK
- bike tb's and fuel rail / or converted carbs and injectors fitted to inlet manifold
- some kind of throttle position sensor
- fuel return line to the tank/swirl pot
- megasquirt/spark (much advantage over using a distributor??) ecu
You will also need
A crank position sensor, both the toothed wheel (that can be fixed to the front pulley) and the variable reluctance sensor.
A high pressure injection fuel pump and appropriate filter
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tks
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| posted on 31/3/06 at 08:19 PM |
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Advantage
The spark renewal is the best investment megasquirt and the injection systems make.
If you look at the BHP's from the 80 to now i say 60% is only because the Spark just comes on time......
i mean to say that as you can imagine
the spark is really really important.
If it comes to soon you are braking the engine, if it comes to late it dies for a small amount of time...
Its the reason wy they in F1 etc always look to revs==> sparks /min! the more revs the more BHP! on the same displacement.
sow i would go 100% for DIY Injection with bike Throttle bodies.
also i'm sure your carbs can be fixed carbs are just complex mechanically....
sow they will give you the funds to switch to the DIY EFI rout..
Regards,
Tks
The above comments are always meant to be from the above persons perspective.
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mark chandler
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| posted on 31/3/06 at 08:33 PM |
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You could of course drop some injectors into the inlet manifold, use the Webers as throttle bodies and run with basic megasquirt, leaving the sparks
with what you have.
You will need to install a TPS (This can run off the throttle cable, be linked to the pedal etc, no reason why it has to live on the end of the carb
linkage) , efi pump, fuel rail and pressure regulator.
Then upgrade at a later stage to squirt & Spark and TB's if you are not satisfied.
Regards Mark
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billy
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| posted on 31/3/06 at 08:38 PM |
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why dont you try bike carbs? theres a good write up in ppc mag last month, telling you all about it
luego-lo-cost finished,vauxhall 16v 2.0,twin 45s de-dion rear set up
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omega0684
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| posted on 31/3/06 at 08:40 PM |
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have you thought bout supercharging or turboing instead of throttle boddies and megasquirt/megajolt?
I love Pinto's, even if i did get mine from P&O!
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Dusty
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| posted on 31/3/06 at 09:21 PM |
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You say the carbs are correctly jetted for your setup but I doubt it. You could just keep them on, set lean for SVA and then get it rolling roaded
before deciding on change. If you do change then I would vote bike carbs. Easy to set up, cheapish, powerful and better than 45's throughout the
rev range.
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Megatron-UK
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| posted on 31/3/06 at 09:25 PM |
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quote:
Originally posted by omega0684
have you thought bout supercharging or turboing instead of throttle boddies and megasquirt/megajolt?
Turbo's are for my other cars: a twin turbo Supra and a mk1 MR2 with a 2.0 turbo lump from the mk2 MR2 (only the 3rd uk car to be converted)...
great fun and make excellent road cars - but I really prefer the noise and response of carbs for fun and track use
Thanks for the replies folks, all really helpful. We're going to spend the weekend looking over the carbs again, just to make sure we
haven't cocked anything up, then think about where to go from there - bike carbs (easier option) or bike throttle bodies (better option) seem
like the way to go - megaspark may even be something to think about if we stick with carbs.
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Megatron-UK
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| posted on 31/3/06 at 09:31 PM |
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quote:
Originally posted by Dusty
You say the carbs are correctly jetted for your setup but I doubt it. You could just keep them on, set lean for SVA and then get it rolling roaded
before deciding on change. If you do change then I would vote bike carbs. Easy to set up, cheapish, powerful and better than 45's throughout the
rev range.
Specs of what the carbs are running is as followed (I made sure I wrote it all down when ordering the new parts):
36mm chokes
140 Main jets
55f9 Idle Jets
180 Air correctors
F9 Emulsion tubes
40 Pump jets
4.5 Aux venturis
These were mainly gained from Dave Andrews site and his jetting software - and confirmed by a few other sources. The same specs, bar bigger 37mm
chokes, but in Dellorto terms, were bought and fitted to the 45 DHLA's in the Escort and it runs fantastically well.
We'll check it all over again and see if we haven't made some stupid mistake somewhere, like having the timing set wrong.
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Megatron-UK
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| posted on 1/4/06 at 04:07 PM |
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Spent most of today stripping things down and building them back up - back to starters with cam timing and ignition timing... flushed all the petrol
out and filled back up with new Shell Optimax.
It took ages to get it back running, but eventually it seems to be better than before; though one of the carbs seems to have developed a leak -
possibly due to standing.
Anyway, definitely better now - but as to how good it actually performs I'm not sure - really need to get it rolling roaded and see what the
emissions are like.... bike carbs and spark-only ecu may still be an option.
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britishtrident
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| posted on 1/4/06 at 04:50 PM |
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Webers can't leak -- it must be flooding -- check float heights, condition of float valves and most likely cause fuel pump presure.
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greggors84
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| posted on 1/4/06 at 07:26 PM |
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Whats the best way to check fuel pump pressure?
Chris
The Magnificent 7!
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britishtrident
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| posted on 1/4/06 at 07:54 PM |
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Any old gauge will do provided it is the right range, for carbs either a hand held pressure-vacum gauge like this is cheap will allow checking of
both output pressure and suction.
http://cgi.ebay.co.uk/VACUUM-GAUGE-Good_W0QQitemZ8051349322QQcategoryZ122139QQrdZ1QQcmdZViewItem
Or for better gear this guy has kit made up.
Ooops wrong ebay shop try this url instead
http://search.ebay.co.uk/_W0QQsassZgaugesandthingsQQhtZ-1
[Edited on 1/4/06 by britishtrident]
 
Rescued attachment db_2.JPG
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