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?

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.

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.

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]

quote:

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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

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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

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

why dont you try bike carbs? theres a good write up in ppc mag last month, telling you all about it

have you thought bout supercharging or turboing instead of throttle boddies and megasquirt/megajolt?

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.

quote:

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Originally posted by omega0684
have you thought bout supercharging or turboing instead of throttle boddies and megasquirt/megajolt?

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quote:

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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.

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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.

Webers can't leak -- it must be flooding -- check float heights, condition of float valves and most likely cause fuel pump presure.

Whats the best way to check fuel pump pressure?

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]
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