My BX14 RE- Sold.

[rutter123]

Twin SU's on a 1977 Dolly Sprint circa 1996 but they got junked cos they were s##t in favour of a twin40s which were really good, so good in fact they blew the engine up, knock knock.
Was prob the last carbed car I had.

[jamescarruthers]

Well done, this is good but if reasoned lateral thinking to swap the good bits to the copy carb. Pleased it is running well for you now. Fingers crossed it stays that way.

[Kitch]

Carburettors! Last time I had the pleasures of them was at the very end of the last century. Since then, choice has been decidedly diesel. Not missing the HT and plugs, either. Or the vapour locking. Or the in-tank pumps. Or the mpg.
Hey, ho.

I hate carbs with a passion. I know they were all we had, but the move to injection took far too long, IMO. My mk1 TRS has a Weber and it drives like shit. Good for one of those, mind, but compared with the 16v it's awful. Lumpy, has a mind of its own when hot starting (though cold starting I have to admit, it's amazing!) Tweaked it and tweaked it as good as it will get, but sometimes you need electronics.

[white exec]

Wonder whether this is of any help for the 16TRS... Ours had a ?? twin-choke Weber too, iirc.
viewtopic.php?p=268719#p268719

[Fumbler]

Carburettors! Last time I had the pleasures of them was at the very end of the last century. Since then, choice has been decidedly diesel. Not missing the HT and plugs, either. Or the vapour locking. Or the in-tank pumps. Or the mpg.
Hey, ho.

I hate carbs with a passion. I know they were all we had, but the move to injection took far too long, IMO. My mk1 TRS has a Weber and it drives like shit. Good for one of those, mind, but compared with the 16v it's awful. Lumpy, has a mind of its own when hot starting (though cold starting I have to admit, it's amazing!) Tweaked it and tweaked it as good as it will get, but sometimes you need electronics.

With carbs it's a bit of a roulette wheel with what you get. There are some super reliable ones, like the SU, then there are ones which cannot be adjusted or they run like shite, such as the Japanese carbs, or there are others which just din't like being, well, a carburettor.

I will say that your TRS shouldn't be lumpy and all over the place at idle. A gasket refresh and a trip to the ultrasonic bath usually helps with things, but as you say, there comes a point when injection is just better in every single way.

[panky]

I've converted both my Commer campers from the rubbish Zeniths to SU's and they run superbly. More power and torque, better fuel consumption with just the dashpot to top up occasionally - great carbs. I've often wondered if a SU conversion for the BX carb engines would work.

[Fumbler]

I've converted both my Commer campers from the rubbish Zeniths to SU's and they run superbly. More power and torque, better fuel consumption with just the dashpot to top up occasionally - great carbs. I've often wondered if a SU conversion for the BX carb engines would work.

With an adapter on the manifold, it'd work. It would decrease power, though, so I'd probably want to make a custom manifold and have two.

Speaking of carburettor swaps, I'm not content on having this one in the car. At some point I want to replace the manifold so I can put in a Solex 32-34 twin barrel carb, because more power, better parts availability and support, thanks to it being fitted to popular Peugeot 205 models. There's a wealth of knowledge on 205 forums so that would be a worthy contender.

I either do that or I buy/make a custom manifold with which I can put any carburettor (or even Holley EFI) on and never worry about stupidity with obscure Solexes ever again.

[jamescarruthers]

Wasn’t the AX GT set up a nice little conversion for the BX TU?

[Fumbler]

Wasn’t the AX GT set up a nice little conversion for the BX TU?

I believe so. The problem is that there isn't an abundance of parts anymore, or, indeed, ever.

[panky]

An adapter would cause problems but if the manifold was modded to take the side draught SU, or better still a custom manifold, the 1 3/4" SU is good for 130bhp (in the right tune and engine) so it's food for thought.

I had a custom manifold made for my 1725 Rapier engined Camper and it goes very well ( had it almost round to the zero stop pin from the opposite direction)



And for the standard manifold the mod is quite simple

Down draught Zenith connection removed and closed off and stub for SU added

[Fumbler]

An adapter would cause problems but if the manifold was modded to take the side draught SU, or better still a custom manifold, the 1 3/4" SU is good for 130bhp (in the right tune and engine) so it's food for thought.

I had a custom manifold made for my 1725 Rapier engined Camper and it goes very well ( had it almost round to the zero stop pin from the opposite direction)



And for the standard manifold the mod is quite simple

Down draught Zenith connection removed and closed off and stub for SU added

Food for thought. If I ever get into TIG welding or get good at MIG, I'll set about making a manifold. It would definitely fix my problems once and for all.

[white exec]

Those large-bore SU's were quite something. Rover P5 had a single 2" on its 3L straight six. All the P6's had SU's too, right up to the appearance of EFi on the 3500 SD1. Our P6 3500S (a pair of SU HD's) was really rather swift, and what seemed like constant torque right up to 122mph.

Easy to maintain, especially if you ignored the advice to owners of earlier Austin-Morris-Leyland cars to fill the dashpot with "engine oil" - which back then usually meant 20W50, and was way too thick. SAE20 or 30 was SU's recommendation, iirc.

Balancing a pair (or even three) was really straightforward with an inexpensive Gunson's Carbalancer (Halfr**ds sold some useful stuff in those days), and I could set SU mixture blindfolded, using the jet nut and the jiggle pin.

Never got on with the Strombergs which Triumph used. They must have been a way of getting around SU's patented design.

[Fumbler]

PXL_20210605_161810827.jpg

PXL_20210605_161821286.jpg

Here goes nothing

[panky]

I use 20/50 in the 'Big Camper' dash pot with it's modified needle, any thinner causes issues, but I need to use EP 90 in the Rapier engined one ( in my profile Pic) otherwise the engine bogs down as the piston rises to quickly weakening the mixture. I've already got two springs on the piston to stop it fluttering so it just goes to show if you wander outside a standard set up the be prepared to experiment.
I also use 20/50 in my Mini Cooper and Morris Traveller (when it's running ) as recommended by many owners. Some find the SU oil, which is basically SAEW20, to work well but then again I'm not running standard set ups so a bit of trial and error is needed.

[panky]

Here goes nothing

Just a tickle with the welder needed
Sorry about the SU hijack by the way