Potential Project Car - Should I?

It's home!



But not without issues, and I need some advice on carbs.

It's running twin Weber 40 DCOEs and it has a spluttering problem at around 3k RPM. It doesn't do it when it's cold and presumably the auto choke is on, but does when its up to temp.

The spark plugs are pretty rusty so I'm going to change them to make sure its not an ignition problem, but fear that would happen across the whole rev range.

The previous owner told me the carbs were tuned at the MOT last month, but I can't help but think something needs adjusting one them.

This is the first car I have owned with twin carbs so any advise you be appreciated:

 
New plugs and getting the carbs balanced should sort you out.
It might be worth investing in a carb balencer as I found webers had a tendancy to go adrift after a while.
Dead easy to do after a bit of reading on how they adjust.
Get some filters too, before you suck something in the engine doesn't like.

If it's still a bit rough after that it might need a rejet asuming the engine is in good nick.
 
Easy way to get a (very) rough idea on carb tuning is to stick a bit of flexible tubing down just into the inlet and listen to the pitch of the sound at the other end. The pitch will vary depending on the amount of air the carb is sucking in, it should be the same sound across all of the inlets.

Obviously to do anything more you want some proper measuring equipment (balancer) but it might give you a clue as to what's up for now. If you can get the carbs roughly right it may be worth investing in a proper tune up, usually £300-500 for full setup on a rolling road including full carb adjustment. Which thinking about it is a reasonable investment usually, but compared to the £1,500 you've spend on the car is a bit steep :D

Bargain :)
 
Perywinkle said:
New plugs and getting the carbs balanced should sort you out.
It might be worth investing in a carb balencer as I found webers had a tendancy to go adrift after a while.
Dead easy to do after a bit of reading on how they adjust.
Get some filters too, before you suck something in the engine doesn't like.

If it's still a bit rough after that it might need a rejet asuming the engine is in good nick.
Click to expand...

Got some new pipercross filters on order :)

Thanks for the advice on the carb balancer, I'll look into how they work. Would I not need to get it rolling roaded after in any case?
 
Ste said:
Easy way to get a (very) rough idea on carb tuning is to stick a bit of flexible tubing down just into the inlet and listen to the pitch of the sound at the other end. The pitch will vary depending on the amount of air the carb is sucking in, it should be the same sound across all of the inlets.

Obviously to do anything more you want some proper measuring equipment (balancer) but it might give you a clue as to what's up for now. If you can get the carbs roughly right it may be worth investing in a proper tune up, usually £300-500 for full setup on a rolling road including full carb adjustment. Which thinking about it is a reasonable investment usually, but compared to the £1,500 you've spend on the car is a bit steep :D

Bargain :)
Click to expand...

Thanks, I'll give this a go tonight. If I have no joy trying to tune it myself I might as well get a specialist to do it so I know it's right.

Another job tonight is changing the plugs, fitting a new battery and removing some of the surface rust from the chrome work :)
 
Spluttering would be a tuning issue. The flexible pipe advice is good; and that will get you a generally good balance. A full service as you have now taken ownership is not a bad idea either.

Checking the function of any throttle/choke cables is good too.

I have only had experience with HS4 and HS2 carbs unfortunately.

What it may be worth doing for the best tuning is a dyno-run, that will get your tuning to 100%.

Kind regards,

David
 
Perywinkle said:
Heya mate.
Did you ever register for the southern kit car club?
We've got a run out his weekend staring at buck barn if you're interested.
Click to expand...

Hi mate,

Thanks for the offer, but I sold the car a couple of weeks ago. Did a fair bit of work to bring it up to scratch and then it sat there unused so had to let it go :(
 
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