another SU conversion
Posted: Sun Feb 01, 2015 3:57 pm
At very long last... I got the carb and manilfold about 3 months ago but just got round to doing the swap.
My own humble advice to anyone yet to do this would be: don't underestimate the volume of faffy work involved. I'll admit messing with spanners in the cold doesn't get close to fun for me, so bear that in mind if I sound a tads jaded.
It looks like this, just needs choke connecting at carb end (lost the screw thing, ordered another), and coolant top-up, route the fuel overflow pipe, fix choke firmly into dash...
Here's a bit of what I found out along the way. I've never done this before so had to work a few things out. I did get to see Chan's conversion which helped a lot.
If I was doing this again, I would very definitely do loads of the prep work before even starting - making up a longer throttle cable (about 10" longer); fabricating (or getting) a suitable air inlet to fit the SU; any fabricating for the air inlet side: [I know this isn't muckproof, it'll do for me].
There's a list of bits you need to hand I think, and it's worth having everything ready: 6mm (and maybe 8mm) hose, clips various sizes, air hose, throttle cable bits, inline fuel filter, breather filter, air filter, coolant, gasket material, and more I've probably forgotten.
Basically I'd say the more you can do before taking the old carb off the better, and a lot of the ancilliary stuff can be done in advance I think.
On the SUs, I have two. That's because I bought an OK one off an SJ but found it was missing choke lever and was generally a bit worn. So rather than a rebuild kit, I got a second good one. You either pay top money for a genuine rebuilt, or assume it will need some work. Burlen are good but it takes a bloody age for the bits to arrive I found. Like ~Chan I took the vac advance off the existing 6mm pipe coming out of the SU rather than drill for a new line. Chan was happy his was advancing nicely and as it's a pressure not flow connection it should be OK. Soon see I hope. I understood use an inline fuel filter to step from the 6mm incoming to 8mm out to carb. On mine I didn't need it, my SU fuel in is 6mm - but I have a fuel filter there anyway.
I've put a BDL needle in but also have a BCZ (recommended alternative according to Ray Rhino). On the charts the BCZ may be a fraction leaner at higher revs, but probably won't notice the difference. If I have a problem with emmissions it may be handy, not sure really!!
I got a manifold from Richard Rockwatt. I know Chan made a really nice one but I think it cost him over a hundred, plus all the work. Richard's are about 160 plus the donor manifold and shipping - 200 really once you're done.
Yet to fire it up of course - it had better work...
I hope this may be useful to someone out there considering. And to the experts, if you spot anything dodgy in the pics above, do let me know !
My own humble advice to anyone yet to do this would be: don't underestimate the volume of faffy work involved. I'll admit messing with spanners in the cold doesn't get close to fun for me, so bear that in mind if I sound a tads jaded.
It looks like this, just needs choke connecting at carb end (lost the screw thing, ordered another), and coolant top-up, route the fuel overflow pipe, fix choke firmly into dash...
Here's a bit of what I found out along the way. I've never done this before so had to work a few things out. I did get to see Chan's conversion which helped a lot.
If I was doing this again, I would very definitely do loads of the prep work before even starting - making up a longer throttle cable (about 10" longer); fabricating (or getting) a suitable air inlet to fit the SU; any fabricating for the air inlet side: [I know this isn't muckproof, it'll do for me].
There's a list of bits you need to hand I think, and it's worth having everything ready: 6mm (and maybe 8mm) hose, clips various sizes, air hose, throttle cable bits, inline fuel filter, breather filter, air filter, coolant, gasket material, and more I've probably forgotten.
Basically I'd say the more you can do before taking the old carb off the better, and a lot of the ancilliary stuff can be done in advance I think.
On the SUs, I have two. That's because I bought an OK one off an SJ but found it was missing choke lever and was generally a bit worn. So rather than a rebuild kit, I got a second good one. You either pay top money for a genuine rebuilt, or assume it will need some work. Burlen are good but it takes a bloody age for the bits to arrive I found. Like ~Chan I took the vac advance off the existing 6mm pipe coming out of the SU rather than drill for a new line. Chan was happy his was advancing nicely and as it's a pressure not flow connection it should be OK. Soon see I hope. I understood use an inline fuel filter to step from the 6mm incoming to 8mm out to carb. On mine I didn't need it, my SU fuel in is 6mm - but I have a fuel filter there anyway.
I've put a BDL needle in but also have a BCZ (recommended alternative according to Ray Rhino). On the charts the BCZ may be a fraction leaner at higher revs, but probably won't notice the difference. If I have a problem with emmissions it may be handy, not sure really!!
I got a manifold from Richard Rockwatt. I know Chan made a really nice one but I think it cost him over a hundred, plus all the work. Richard's are about 160 plus the donor manifold and shipping - 200 really once you're done.
Yet to fire it up of course - it had better work...
I hope this may be useful to someone out there considering. And to the experts, if you spot anything dodgy in the pics above, do let me know !