Advance curve

[bison]

Gents,
First of all, nice to meet you all at Thenay!.
My little TL performed perfectly, never missed a beat, and the SU conversion is definitely worth doing in my opinion.
Now, before and after fitting the SU, although the plugs are a perfect colour the exhaust is still very sooty. Fuel consumption is 50MPG averall and it's running very nicely.
Here's my theory, the unburnt fuel sooting up the exhaust is escaping before it's burnt, and can only be caused by one of two things, the valve timing is out (which it isn't) or there isn't enough advance on the distributer?. Valve clearances, timing, dwell, compressions etc are all spot on. I was thinking of trying a distributer with a vacuum advance unit fitted.
Now the questions.
I know they have different advance curves, but is the total advance in degrees different?. Which distributer will fit the 845cc engine?, I know the 950 and GTL ones rotate the opposite direction but the points are fitted in the same position, however the bob weights would be rotating in the wrong direction, although I'm sure I can modify that somehow, if it actually matters. And finally, does anyone have a spare distributer for sale?.

Thanks folks.
Alan.

 

[alewis]

Sorry a bit off topic, I had a quick look on the forums and couldn't find much about the SU conversion. Any chance of a pic ?

 

[Cornish4]

Hi Alan, nice to meet you too at Thenay, and have a chat about car stuff. Which dizzy are you looking for? The best to fit is a Ducellior, it's better than the Femsa, (easier to fit and adjust points so I'm told) and it can be converted to electronic ignition which I have done care of Aldon ( part number EP141). Of course I don't know if it will run the opposite way, but I don't see why not if you can get a rotor-arm to suit. Regards Brian.
PS. Of course these dizzies are as fitted to 1108cc engines.

 

[bison]

Hello Alewis
I've got pictures but won't be able to upload them until Monday, sorry. It's a manifold and SU off of a Reliant, practically bolts right on. Faces toward the bulkhead.
Alan.

 

[malcolm]

I've attached a picture .

The 1108 and 956cc distributors are much bigger than the 850cc ones and won't fit. Something like the 123 ignition kits might be an idea if they are available for the 850. Doubt changing the distributor will make much difference to performance. The soot might be in the tailpipe because it's a cold exhaust system - it's left over from start up. A free flow silencer at the rear in place of the under wing one would get rid of it and give you a small performance gain. Otherwise could be running slightly rich but that's better than too lean.

 

[alewis]

Thanks!
I have a couple of spare 2 inch SU's but I fear they are far too big !!!!!

 

[Cornish4]

An 1 1/2 SU would probably do the trick on a 1108cc engine, although the Reliant inlet manifold would need a modification to fit it I think. I wonder if there is a way of fitting twin SUs? Of course there is, anything is possible, but then, sometimes a well tuned bigger single carb is better than smaller twins.
I think Bisons' and his pal Daves' cars had 1 1/4 SUs fitted if Im not very much mistaken, to quote a Murrey Walkerism.

 

[alewis]

Maybe one would work but 2?

+Sorry kind of hijacked this tread, would a good test be after a run run bolt the exhaust from the manifold and see if its black in there ?

 

[pepper]

I love SU carbs, I always think that the bucket with a hole in the bottom and with a tapered needle as a principle of getting fuel into an engine is excellent!

I know a lot of 4x4's and they sweat at Webers and love SU's! when the going gets rocky a Weber can't cope whereas an SU is just smooth and simple

 

[barnfind]

I'm an SU fan as well. What kind of Reliant did the manifold come off?

 

[bison]

Thanks for posting the photo Malcolm.
The Ali manifold is from any Reliant three wheeler, or the little 4 wheeler I think, as is the carb. Yep, it's 1. 1/4", same jetting/needle, in fact all I did was clean the float bowl and fit it, then adjust the main jet a little, works great. Put two T 's in place of the parallel pipes in the heater hoses for the water heated part.
Before I got the Reliant assembly I made a simple manifold for another SU I had, so making one for a GTL should be easy, how about a 45 or 90 degree plumbing fitting?, and perhaps an SU for an 1100 mini might have close jetting?. Just a thought.
Alan.

 

[alewis]

Its a really nice job. Did you solve your initial problem with the soot ?

Many thanks,
Andrew

 

[bison]

No, the exhaust is still sooty, but the plugs are a perfect colour. As Malcolm said, maybe it's just on start up when the engine is cold, but with the water heated manifold it warms up very much quicker. I have a GTL type exhaust system fitted with the silencer at the rear.
I think I'll get a carb rebuild kit with a new needle and jet, see if that makes any change, there are a variety of needles listed for the Reliants, I'll look at the profiles when I see what I've got fitted. Mind you, I like that old addage, "if it aint broke don't fix it"!.
Malcolm, I wonder if the distributer outer casing could be turned down and maybe a spacer made to get the right hight?
Alan.