Mopar Muscle Association UK

Yeah this is brand new though, was replaced with the kit. I know you did Jon, it's quite possibly OK although I would since you problem just relates to the Sec bowl I would be tempted to put the old one back in to eliminate it. I put a brand new cooling system stat in once, got a couple of miles fr...

Indeed, all of the Holley 4150 rebuild kits that have past through my hands come with the Red umbrella's - some were used and some not depending on the style / age of the bowl.

Despite all that, looking at both your float bowls, the bowl floor is slightly raised in the pump area so guess you have bearings in both
My money is still on the needle valve

Sorry chap, I would disagree. Here is a brand new one here direct from Holley that has the red rubber umbrella. I have seen many older units with this too.

You will need to take the diaphragm pump & diaphragm off to check. Your friend might not have replaced this as you have a 50cc pump there and 30cc diaphragms generally come with a standard kit

BTW, the check valve has a long end on it to stop the float bottoming out

This is where mine sits. The spring is a totally different design to yours so no point showing a pic of that but yours must be assembled wrong to sit so low. Is the red rubber check valve fitted - red arrow? I can't see this. This acts to prevent fuel flowing back into the fuel bowl when the accele...

Jon has asked for recommendations based on a 'car is on the road 99% of its life' not what gonna get him down the track quick.

I am merely illustrating what has worked for me with what looks like a similar combo in a similar car

BTW this assumes that your motor is 100% efficient, if you added a factor of say 85-90% you'd end up with a smaller carb....

I have successfully run a 12 with a 650 DP on a 383

The calculation I have always used is cubic inches multiplied by the maximum RPM and divided by 3456

T'as always worked for me

On the basis that it is a relatively light car, having quick gears I would go for the DP all the way. The DP is easily adjustable to overcome most situations where as the Vac carb can become a little more tricky. The combo you have also satisfies the online carb selection thingy that used to be (or ...

Could probably send you another sec float bow, needle valve n float to try....

Worth trying that before doing that before buying a new one...

Float puncture / knackered?

Replace the sec needle valve

I doubt that they will be anything that special but I'm sure they'll do the job

Not wanting to rub the salt in but I used to knock a pair these out on Ebay for under a fiver delivered. Some thought that was expensive.....

Good luck with your tune-up