Replacing Carbs with Fuel Injectors
Discussion
If it's easy to revert to original spec why not .
Where do you draw the line if you wish to use the car regularly and for any distances.
No electronic ignition, no electric fans , no unleaded conversions .
It breaks my heart to see cars that are just shiney exhibition things and not used .
Where do you draw the line if you wish to use the car regularly and for any distances.
No electronic ignition, no electric fans , no unleaded conversions .
It breaks my heart to see cars that are just shiney exhibition things and not used .
Personally it would depend on the exact setup in question. Some classic engines with multiple carbs and a relatively high state of tune can be quite finicky to keep running sweetly and have running/fouling/flat spot issues even when working entirely as designed. Just the nature of the technology. Same goes for some of the horrific carbs used in their later days, with auto chokes, run-on valves, waxstats, vacuum actuators and so on. Junking them and getting a simple EFI system has big benefits.
A straightforward single SU or Solex on a mild-tune saloon? Get it set up right with a good tune on a rolling road and with a distributor with a decent condenser and advance mechanisms and it will be fine. I don't really see what injection brings to the party.
If you're going for improved performance and more power, then that's a whole different ball game.
A straightforward single SU or Solex on a mild-tune saloon? Get it set up right with a good tune on a rolling road and with a distributor with a decent condenser and advance mechanisms and it will be fine. I don't really see what injection brings to the party.
If you're going for improved performance and more power, then that's a whole different ball game.
Not my thing I dont mind a few minor upgrades but for me you lose the essence of it being a classic by replacing the carbs.
Some people do like to change everything to make it like a modern car though. I agree it is better in many ways but for me driving a classic should feel like driving a classic.
The appeal to me is the feedback you get from old cars which moderns are lacking, Next you will say better than efi would be to convert it to electric.
Some people do like to change everything to make it like a modern car though. I agree it is better in many ways but for me driving a classic should feel like driving a classic.
The appeal to me is the feedback you get from old cars which moderns are lacking, Next you will say better than efi would be to convert it to electric.
Some carbs are a pain in the rear, like the solex cars and the zenith carbs that were put on Mercedes Benz in the 60's and 70's. Swapping in throttle body injection or a different carburetor makes sense. Does it make a huge difference? Maybe to fuel mileage if you're running something like a Cadillac or a Jensen but in reality, the main reason carbs have a bad reputation is because the ones on most cars that are on the road are worn the heck out. A rebuilt or new replacement carb will probably run perfectly.
I put a new edelbrock carb on my old 73 GMC Sierra Grand which had a worn out 2 bbl and it transformed the truck. Easy starts, clean burn and it felt like it added 100hp to the engine.
I put a new edelbrock carb on my old 73 GMC Sierra Grand which had a worn out 2 bbl and it transformed the truck. Easy starts, clean burn and it felt like it added 100hp to the engine.
Jenvey make a classic set of throttle bodies heritage’ to look like carbs.
https://store.jenvey.co.uk/throttle-bodies-and-com...
https://store.jenvey.co.uk/throttle-bodies-and-com...
Simes205 said:
Jenvey make a classic set of throttle bodies heritage’ to look like carbs.
https://store.jenvey.co.uk/throttle-bodies-and-com...
Good idea, but throttle bodies look great, and look great in any engine bay.https://store.jenvey.co.uk/throttle-bodies-and-com...
If you want twin 40’s etc, fit Webers
I’m debating with myself at present about replacing the twin 50 DCOE Webbers on my Mk 1 RS2 to Injection.
It’s been a b
h to start when it’s cold outside, although the last time I attempted this last week, I was so certain it would not I did not even bother to open the Garage door. By pumping the throttle whilst cranking [ after 4/5 pumps before cranking ] it fired up fairly quickly
As its pretty much a race spec Pinto built by the late Ron Harris, your expect it to be “cammy” which it is, although once up on the cam around 3250 ish its lovely and smooth and just pulls steadily.
It’s the in-between part from low throttle up to mid where you have to be super careful with the throttle not to stall the engine, its better under load.
So, I’m thinking, put it on throttle bodies, poss the Jenvey carb look alikes, better starting, smother transition etc, although not likely to give any more power.
But, it’s not my daily [ thankfully!! ] it is really a Toy that is filled with nostalgia for me and a sound investment and Always makes me smile [ unless it won’t start!! ] and, do I really want to iron out some of its Character ? As time passes I am thinking no, leave it alone, that is until the Barsteward won’t start again
Now, about the rear axle droning noise, rattly gear stick, one speed wipers,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
It’s been a b
h to start when it’s cold outside, although the last time I attempted this last week, I was so certain it would not I did not even bother to open the Garage door. By pumping the throttle whilst cranking [ after 4/5 pumps before cranking ] it fired up fairly quickly As its pretty much a race spec Pinto built by the late Ron Harris, your expect it to be “cammy” which it is, although once up on the cam around 3250 ish its lovely and smooth and just pulls steadily.
It’s the in-between part from low throttle up to mid where you have to be super careful with the throttle not to stall the engine, its better under load.
So, I’m thinking, put it on throttle bodies, poss the Jenvey carb look alikes, better starting, smother transition etc, although not likely to give any more power.
But, it’s not my daily [ thankfully!! ] it is really a Toy that is filled with nostalgia for me and a sound investment and Always makes me smile [ unless it won’t start!! ] and, do I really want to iron out some of its Character ? As time passes I am thinking no, leave it alone, that is until the Barsteward won’t start again
Now, about the rear axle droning noise, rattly gear stick, one speed wipers,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Nampahc Niloc said:
I’ve been watching a lot of Car SOS recently and Fuzz Townsend seems obsessed with replacing Carburettors with fuel injectors. What do people think of this? I understand all the benefits, but it’s not in keeping with the original vehicle.
I think it all depends on the vehicle, and parts availability for the carb setup.With the impending move to E10 fuel and even higher ethanol content, many older carbs might not have the parts support for E10 fuel compatibility and that could start to pose an fuel leak and fire issue and that's where a stand alone EFI conversion will start to make sense.
Of course, if you have a very original classic car, or concours show car, then EFI isn't really an option, or the car is of an age where it really isn't any point, eg. you are not going to fit a TB FI system to a side-value E103 Ford Pop....
The "Why", as OldGermanHeaps said is simple - more accurate fueling and timing (assuming you aren't nuts and install electronic ignition at the same time) so you use less fuel, get more power, and reduce wear on the engine (from over and under fueling/inefficient ignition). Even on the best set up carb/points engine you'll be lucky to have the correct fuel/air/timing combination at more than a couple of RPM/load points.
Now if you just like to polish your car/only take it out for the odd summer Sunday for a potter/just prefer to keep it original that's fine. If you actually like to use your classic though and cover some miles though there are a lot of advantages.
My car hasn't made it to EFi yet, partly down to me procrastinating (Custom fuel tank with built in swirl pot/fuel pump or external? Individual/paired/or single throttle body? Etc) but in no small part because I fitted mappable electronic ignition and that alone made such a huge difference to the drivability and usability of the car! No more a choice between a flat spot below 1,500RPM or one at 4,000RPM, or between 2,000RPM ro pull away of pinking at cruise - the best a number of experienced carb. rolling road operators, including famous, now retired ones could manage. No, now even make experts who drive it assume I must have swapped the 1.3 for the 1.5.
Now if you just like to polish your car/only take it out for the odd summer Sunday for a potter/just prefer to keep it original that's fine. If you actually like to use your classic though and cover some miles though there are a lot of advantages.
My car hasn't made it to EFi yet, partly down to me procrastinating (Custom fuel tank with built in swirl pot/fuel pump or external? Individual/paired/or single throttle body? Etc) but in no small part because I fitted mappable electronic ignition and that alone made such a huge difference to the drivability and usability of the car! No more a choice between a flat spot below 1,500RPM or one at 4,000RPM, or between 2,000RPM ro pull away of pinking at cruise - the best a number of experienced carb. rolling road operators, including famous, now retired ones could manage. No, now even make experts who drive it assume I must have swapped the 1.3 for the 1.5.
I've thought about adding injection and mappable ignition to my Vauxhalls for the same reason - it's possible to get it to run better pretty much all the time, where the combination of standard ignition and carbs presents a compromise. Get it set up for optimum performance and the economy suffers and it's a pig in traffic. I know people will say I shouldn't be worrying about economy for the mileage I am doing even in a normal year, but there's a marked contrast in mine - mid-30s on a motorway run down to very low 20s on A-roads means that it's always in mind.
It's only the cost of the conversion that's stopping me at the moment, and the fact that it all has to be done from scratch, there's no off-the-shelf kit like there is for some more popular vehicles. I wish I'd put a fuel return line in when I was rebuilding the Sportshatch and it was all in bits, I could have made a much neater job of it than adding it later.
I should add - I'm obsessed with originality, so the only way I'd do this is if I could make it simple to revert back to the original set-up, but I can't see that being much of an issue. And it'd probably make me use the cars a bit more, which must be a good thing.
It's only the cost of the conversion that's stopping me at the moment, and the fact that it all has to be done from scratch, there's no off-the-shelf kit like there is for some more popular vehicles. I wish I'd put a fuel return line in when I was rebuilding the Sportshatch and it was all in bits, I could have made a much neater job of it than adding it later.
I should add - I'm obsessed with originality, so the only way I'd do this is if I could make it simple to revert back to the original set-up, but I can't see that being much of an issue. And it'd probably make me use the cars a bit more, which must be a good thing.
i did this to a carb car last year...ends up costing a fair chunk, then unless its popular car you need alot of help getting it running right , got mine starting and driving "okay" but ideally it needs a pro to help set it up ...if its a commonly done engine chances are you can get a map off another owner and away you go
I've never seen Car SOS as a dedicated restoration program, more of a rebuild as a present sort of thing. Usually the recipients of the finished vehicle have disabilities or some sort of difficulty in life so making a car a bit more modern and reliable would be good for them. Besides, I'd prefer to see a classic car on the road with a bit of modern technology in rather than it potentially sat on a drive rotting away again because they can't find someone to tune the carbs.
Mark A S said:
I’m debating with myself at present about replacing the twin 50 DCOE Webbers on my Mk 1 RS2 to Injection.
It’s been a bh to start when it’s cold outside, although the last time I attempted this last week, I was so certain it would not I did not even bother to open the Garage door. By pumping the throttle whilst cranking [ after 4/5 pumps before cranking ] it fired up fairly quickly
Do they have a diaphragm? If they do, any leak (even just a pin hole) will cause starting issues. Might be worth checking....It’s been a b
h to start when it’s cold outside, although the last time I attempted this last week, I was so certain it would not I did not even bother to open the Garage door. By pumping the throttle whilst cranking [ after 4/5 pumps before cranking ] it fired up fairly quickly I have a 1960 Triumph TR3a to which I fitted the Jenvey Heritage throttle bodies with an Emerald ECU. The car has been mildly tuned prior to this, re-worked cylinder head, 4 branch exhaust, TR4a inlet manifold and a slightly revised camshaft with focus on torque. On the rolling road at Emerald it showed 117 bhp at 5k rpm I then thought of the fuel injection route purely to see what sort of difference it would make to an old engine design. After fitting it went back on the rolling road for tuning and then showed 138bhp, again at 5k rpm. Performance of the engine is like night and day, very easy starting, great tick-over, absolutely smooth throughout the rev range and improved fuel consumption. It makes it a delight to drive and demonstrates to me what modern technology can do to a 1948 engine design. It is expensive and cannot be justified economically, just something I wanted to do.
all the best
Tim
all the best
Tim
Mark A S said:
I’m debating with myself at present about replacing the twin 50 DCOE Webbers on my Mk 1 RS2 to Injection.
stuff about high compression/lairy cam/huge carbs motor which is a bh to start when cold - but is fab when warmed up and running in ideal rev range
+
Now, about the rear axle droning noise, rattly gear stick, one speed wipers,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
i feel your pain as experienced same hassle trying to start my full race bda last month on cold damp morning. After a few attempts and inevitable flooding - got handy at whipping plugs out - and heating them up - in fact in the end changed plugs too etc etc. so this weekend i decided to do something about it.stuff about high compression/lairy cam/huge carbs motor which is a b
h to start when cold - but is fab when warmed up and running in ideal rev range+
Now, about the rear axle droning noise, rattly gear stick, one speed wipers,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Step 1 - purchased butane powered catering pro torch for 30 quid which means BEFORE i have even bothered to crank it - with my now extensive experience taking plugs out in a hurry and drying them when flooded - even with 48's jetted for extremely cammy engine - i hope i now have a sporting chance of getting it firing before it floods without emptying a cigarette lighter. My starting procedure is exactly the same as yours after fuel pump has built pressure - but if it does not catch after a few attempts - it floods
Step 2 - Fuel injection. There was only one solution for me - partly for race eligibility - lucas mechanical fuel injection. A wallet emptying search found a genuine set up off an old group 6 sportscar which ran a bda. i'm only using lucas because it was period (it also looks the tits) and i have always wanted this set up and it won't harm the value of the car if circumstances change and i need to move it on. Arrives this week - credit card bill won't have to be paid for a while
Here's a pic of another project I'm finishing off with jenvey throttle bodies - which will have a perspex cover over a cowl in the bonnet. Jag V6 in a mk1 mx5. The motor of course never ran on carbs - but stock twin throttle body set up did not have same sex appeal and outright power potential - is it sensible = No . Even after a lot of mapping - will it run very smoothly at low rpm/cold = doubtful. Under load above 4k - is induction noise like a 6r4 on crack? f
k yeah!re - "Now, about the rear axle droning noise, rattly gear stick, one speed wipers,,,,,,,,,,,,,,,,,,,,,,,,,,,,,"yeah i have those problems - diff is more or less locked - might be ok and sound as does normally - but i need to check oil - gear knob fell off on track and ended up under pedals - loctite solution planned - wipers - they are so s
t that if you turn them on as i did once - you just slowly smear the screen - on to do listA Hillborn injection set up came with my car boxed up in the boot with instructions when it came over - I might be tempted to part with to contribute to cost of buying lucas set up. I am not sure it was homologated in period for my car but was apparently fitted to my bd when motor was in a single seater in states. If interested and you could get it to work on pinto - message me and I will take some pics when i go up to see car this week - pic I have of Hilborn at moment at the end of post.
Mark A S said:
I’m debating with myself at present about replacing the twin 50 DCOE Webbers on my Mk 1 RS2 to Injection.
It’s been a bh to start when it’s cold outside, although the last time I attempted this last week, I was so certain it would not I did not even bother to open the Garage door. By pumping the throttle whilst cranking [ after 4/5 pumps before cranking ] it fired up fairly quickly
What fuel pump are you running?It’s been a b
h to start when it’s cold outside, although the last time I attempted this last week, I was so certain it would not I did not even bother to open the Garage door. By pumping the throttle whilst cranking [ after 4/5 pumps before cranking ] it fired up fairly quickly And 50's are big.....I would have thought about 7-8 pumps on the throttle before be reqd to fill them up first before cranking it?
I used to do 5-6 pumps on the 45's on my Sunbeam-Lotus when cold....
V- power, fairly fresh as well. Reducing the choke size will probably help, but then will drop top end a little, ho hum
Will try 7/8 pumps then some gentle "pumping" next time. In the warm months, 5/6 pumps and its away fairly easily.
Don't think Webbers have a diaphragm, will check it out though, thanks.
Thanks for the offer of the Hillborn injection, as its just a "toy" IF i change it to injection, it will be modern stuff, although, TBH i think I'll keep with the Carbs, as once i have perfected cold weather starting, reduced the choke size maybe, i am sure it will improve, but, as i said earlier i rather like its "old School" charm.
I have had Full house BD's on Lucas 8mm injection, wonderful when set up well, but there is no part throttle running facility in it so it makes it Horrible for road use, great for a race engine though as that's what its designed for.
From memory [ bear in mind this is around 40 years ago ] to start from cold, put the pumps on, ignition off, let the pressure build up to around 120, throttle full down, crank [ mine was on 24v starting ] for 5/6 seconds, throttle up, ign on, Start, which it normally did ok, hold at around 2.5k until it would tick over at 1800.
Make sure the seals in the metering unit are all fresh, when they leak,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Will try 7/8 pumps then some gentle "pumping" next time. In the warm months, 5/6 pumps and its away fairly easily.
Don't think Webbers have a diaphragm, will check it out though, thanks.
Thanks for the offer of the Hillborn injection, as its just a "toy" IF i change it to injection, it will be modern stuff, although, TBH i think I'll keep with the Carbs, as once i have perfected cold weather starting, reduced the choke size maybe, i am sure it will improve, but, as i said earlier i rather like its "old School" charm.
I have had Full house BD's on Lucas 8mm injection, wonderful when set up well, but there is no part throttle running facility in it so it makes it Horrible for road use, great for a race engine though as that's what its designed for.
From memory [ bear in mind this is around 40 years ago ] to start from cold, put the pumps on, ignition off, let the pressure build up to around 120, throttle full down, crank [ mine was on 24v starting ] for 5/6 seconds, throttle up, ign on, Start, which it normally did ok, hold at around 2.5k until it would tick over at 1800.
Make sure the seals in the metering unit are all fresh, when they leak,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
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