DRLA 36s and how to stop my bus backfiring?

Sarah was beginning to wish she'd never mentioned bloody Dellortos...

 

Just to explain (having read my notes from 5 years ago): the 127 mains are much too big. Plenty of rompage, but they just hose fuel into the engine. Fuel consumption isn't the best. The "standard" fitting seems to be 118s (which I had and ran fine, with reduced rompage). Mr Rolling road, having thrashed my motor, recommended going up to 123s with 175 airs. They didn't have any, so I ended up with 127s. I've yet to try 123s.

 

i did all that , I CNCd my 28 vents ,velocity stacks and welded filter bases . Non generic manifolds are around if you search that are for 36s .. does it make a difference… in my head it does There is a lot of conflicting advice here but if both carbs are balanced and open at exactly the same time you won’t be far wrong . I don’t trust RRs they don’t change jets & screw with your timing .

 

Might well be, although a bit thirsty. Give 'em a go. Can always change them later.

 

A long air filter stud broke when I was driving down the M1.

It fell down the throat of the carb, jamming the butterfly open resulting in the bus accelerating on its own.

It then made its way to the cylinder head.

Velocity stacks (if fitted) would probably have prevented my situation.

There is your justification for velocity stacks moving to the essential list

 

On the way on holiday via Eddie's birthday party.

Meant my van spent a summer Camping at Vic Farm without me. I then got a lift to Techenders from Alex and then got recovered to the engine builders after techenders finished!

 

8

Thanks for your reply, but my servo was plumbed into 3 and 4 cylinders.
Any way it's all in the past now.
.

 

"The book shows carb top lying on it's back, it must be held at 90 degs with the float hinge at the top because the valve is spring loaded."

this- absolutely.... it becomes apparent when you do it but had me puzzled for a while if you recall!

 

Me too!

 

can I ask what engine your 36s are on ?

 

They don't mess with MY timing, though I concede they often want to. I loose heart when they say stupid things like "I won't do the run without disconnecting the vac advance" because it only proves they don't really know what they are doing. A proper one will change jets, that's 100% the job! But yeah, for me I just wanted them to strap it down, do the run and show me the graph - I'll do what needs doing from that point. Then I realised I didn't need to put up with them if I installed an AFR meter and bought some jets. I don't really care how many peak HP I have but one run and a graph does give you a view of how your engine performs overall if you're the tinkering type.

 

Hold off on your trumpets, madam. I may have a set in the garage.

 

They used to be a bit cheaper but such is life. Those are a good height. General rule is taller the better but you want about the diameter of the hole (40mm) above them/below the filter top.

 

A 1776 with DRLA 40s choked down to 28mm.

The default jetting I got from "fidodido" (@Dicky 's mate?) on here, who appeared to know his onions, and it worked just fine:

28/55 or 57/.2/118/180/33

 

Also possibly a set of 118s

 

Those sound impossibly small to me. A 34pict3 main jet is 127.5 with it's 26mm venturi
By my reckoning the 127's Sarah already has would be about right for 28 vents and it proves thirsty she could rolling road some time to get the size down and proven to be safe.

 

Too late. She's gone mad. Ambulance has just left.