So the story of my Jag has gone round work like wild fire, everyone has had a good giggle which is nice. Today as I walked past the loading dock guy he shouts.

"Triple Su's and shave the pistons mate thats what you need to do"

Obviously I replied with

"Thats the plan"

I have no idea what he was talking about, Ive googled Triple Sus and found out they are Carburettors but what is the benefit of having 1 extra one? and what does shaving the pistons do?

 

33% more fun to tune, and worse fuel consumption.

 

Three carb's of any specie look better than only two? run better? yes, in some circumstance. usually worse.


Shaving engine pistons seems counter productive.


Perhaps shaving the pistons in the SU carbs has a benefit, real or imagined?


Or go full bore. Three Webber DHOE 45's!!!


Carl

 

His little joke I think

In olden times it was "lower the door handles and take twenty thou off the dipstick!" lame then and hasnt improved with time.

Sounds like the Jag aura is working at your office

 

Kinda like "if it don't go, chrome it' ?


Carl

 

If it's of no value, then it begs the question, why did jaguar fit them to the E-Type etc?
Must have had some advantage, what else was changed on the triple SU carbed engines?

 

I have no experience with carburetors on e-types but typically the more available air flow the more peak power the car can make. The trade off is that the torque and hp will appear higher in the rev range.

On a tarted up sports car the idea is that it looks more like a race car with triple carbs instead of a single or dual carb set up. So the purpose of more carbs is marketing with a pinch of extra performance to back it up.

With the larger carb capacity Jagur probably also changed the cams by increasing the intake valve duration and exhaust valve overlap. This is what one does to try to get the intake charge moving despite the larger cross section of excess carb airflow capacity. The air has to move to get the air and fuel to mix properly.

The car will be more sensitive to tuning with three carbs. I would still want them for the appearance, knowing that they will require extra carb service and more tune ups.

 

really , how hard can it be?

 

Here's the E Type ones.........

 

Well, I had spent years playing with bikes with 4 x mikuni's or 4 x cv's or 4 x flat slides, and never thought twice about it. Then suddenly had twin SU's and went into a panic, but Grant Francis and cat_as-trophy eased me into working on them myself.

My fuel economy dropped from 21L/100 km to around 13l/100km

 

I saw a website somewhere advertising the advantages of Mikunis fitted to the XK engine.
Possibly a stage too far from original for me, but looked worth considering over the expensive triple weber set up my heart desires.

 

Possibly neither did he. Over here we call such people 'bench racers'- they talk a good game but really have no experience or real knowledge to back up their statements.

If he was not just joking around, he possibly meant 'shaving the cylinder head' (to increase compression) and not 'shaving the pistons' which would decrease compression. For fun, next time ask the guy if he meant 'shaving the head'- then pull out a razor and ask if he'd like to volunteer his own head to practice on.

Adding more or bigger carbs rarely does much for performance unless the rest of the engine is modified to take advantage. More carbs is not always better but always looks impressive.

 

Next you'll be saying that racing stripes are no good.

 

You have to raise the rear of the car using 'shackles' to get any effect from the stripes. That was the hot tip when I was growing up.

 

Thats impressive, you had some good coaches there.

 

It was running so rich I had two black football size ovals on my garage floor from starting it up.
And a split jet tube that was probably pumping fuel out too. Needles were so thin I think fuel was just flowing by and fuel bowl needles were sticking open.

I don't think the carby's had been looked at in years.

 

Yarpos, is that a 265 vally or a 202 holdi?? It ain't a slant, and it certainly don't look like a 'coon 250. Picking an early '70's? Or is it an old 'rana with a worked 186? Looks like something that would have gone up the mountain at some stage. Maybe with Brokky at the wheel.

Now that must have successfully confused all the non Australasian members.

Cheers,
Richard

 

They would have absolutely NFI what you are talking about.

It was a worked over FJ at a multi car club rally I went to a few months ago. Originally a 186 and driven regularly. Sounds the business when running :-)

 

1. Non Aussie agrees, totally!


2. As shaved male heads are stylish, nowadays, who knows? Hide middle age male pattern baldness or streamline. or DIY hair cuts???


3. At one time the HD chopper guys took to SU's off the side. In ordinary riding, the knee a nd the carb sought the same space. No matter, just kick the knee out further. comfort on a hard tail HD???


And, the past time, pull the needle and polish it to improve flow and power. More black smoke. yeah that must mean it is running more powerful!!! It do take more gas to get more power, yo?????


Carl

 

like STROKER MCGURK said, 1955