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View Full Version : Sport carb set up changes.


steg1970
19-08-13, 03:59 PM
I normally run the rally car with the Nova Sport airbox without its lid and the air filter held in with clips. To keep intake air temperatures down I've refitted the air box lid and run some ducting to the front of the car, as per the pic below.

I had the car set up with the old intake, my only question is are the carb settings likely to have changed with this new intake, I.e should I be getting it set up again or will the difference be negligible?

http://i30.photobucket.com/albums/c319/stevo1970/image.jpg

http://http://i30.photobucket.com/albums/c319/stevo1970/image.jpg
meritlover
19-08-13, 07:20 PM
negligible.
Novasport
19-08-13, 08:12 PM
If it is a while since it was last setup I would get them done anyway so they are running their best.
meritlover
19-08-13, 08:15 PM
most carbs are setup with the bonnet open and a huge fan blowing cool air on it while its on the dyno anyway. This means that the carbs werent setup with the same warm air as the engine will see during normal road use, so it wont be miles away. But as said, carbs are primitive devices and will no doubt benefit from being set up again.
steg1970
19-08-13, 10:00 PM
They were only set up in March, it was just the change to the cold air feed I was bothered about.
meritlover
19-08-13, 10:09 PM
as i said.

negligible.
steg1970
25-08-13, 08:33 AM
Well that was a disaster, with the air box lid and duct fitted the car ran like a bag of sh1te! Hesitant and would not rev. All removed and back to normal.
Novasport
25-08-13, 09:41 AM
It may be something to do with the cold air feed. I routed mine toward the radiator and had loads of issues on full throttle. It was being starved of air. I re-routed it down to the other side of the drivers headlamp to where you put yours and it was fine.
Try it without the hose, if it is better then you know it is down to the routing of the hose and it need repositioning.
meritlover
25-08-13, 11:00 AM
the ram-air effect will end up with a more dense charge. As carbs don't compensate for density change, the mixture will be weaker and will loose power. this is why cold air feeds should not be sealed against the OE intake. This means there will be an area of cold air at atmospheric pressure for the carb to suck on at its own free will.