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-   -   webber set up on drifting? (https://www.nopistons.com/race-prep-10/webber-set-up-drifting-72478/)

Dorito Machine 06-03-2009 02:33 PM

i was thinking of going to webber sidedrafts on the streetport 6-port im about to build but ill be using it to drift and was wondering if theres any known issue with using side drafts in drifting?

ruddyrid 10-28-2010 10:58 PM

same here. gonna run a 13b street port with a dellorto carb. any info before i jump?

Lynn E. Hanover 11-23-2010 06:23 AM


Originally Posted by ruddyrid (Post 843944)
same here. gonna run a 13b street port with a dellorto carb. any info before i jump?





I guess you have to ask some old guy about carbs.



Carbs don't like to be bounced around. Carbs don't like being side loaded as in "G" loads.



Carbs like to drive in straight lines at one "G". To work properly the fuel level needs to be constant.



The depth of fuel to some extent controls fuel flow and metering. A deep bowl works better than a



shallow bowl. If you have a tall narrow drinking glass with one pint of water in it, and run around



the kitchen table twice, you might have all of the water still in the glass. Now put that pint of water



into a shallow soup bowl and try again. Not so good this time. So the taller carb like a Weber 48 IDF



works better for performance (high lateral "G") than does the DCOE style.



The DCOEs work fine but expect a bit wider range of mixtures as the "G" load switches from right to left and back



again.



Remember that one "G" load on a fluid container will produce a 45 degree surface in the fluid. Now add to that the chassis roll during the "G" load and you can see the difficulty in controling the fluid depth.



Take the carb to the cleaning tank and fill the bowl about 2/3 full of solvent. Now twist the carb over in every direction to about 50 degrees. Notice that in some cases the fluid is well away from the main jet wells, so the mixture would go way lean for a second or longer, and in other cases the fluid is above the tops of the emultion

wells and would go way over rich for a few seconds.



Fuel injection is used to avoid this mess.



But you can make it work. It is a long painful process.



Make up bowl cover gaskets that cover the whole bowl area. Put in openings only big enough for the float to



operate. This keeps the fuel from climbing higher than that gasket, and keeps it out of the top of the emultion well in the other direction. In all other respects this new gasket must be identicle to the stock gasket.

I have never worked on the carbs you propose to use, but they are (were)used in racing, so it is



possible. In IMSA racing stocks the stock NIKI had to be used. A disaster. The bowls had to be vented with



long tubes sticking straight up out of the carb throat. The original bowl breather tube was removed and another



tube stuck straight up. A side load would fill the breather tubes with fuel and when the car straightened out after a curve, the fuel would fall into the carb and short the plugs out. The three added tall tubes cured the problem. More fuel pressure, and making a stiff needle rather than a spring loaded needle were other mods to be done.



If fuel injection is an option use fuel injection with changable maps.



GOOD LUCK.



Lynn E. Hanover

vosko 12-09-2010 12:46 PM

carbs sound terrible for drifting like already mentioned. you do alot of on/off throttle and part throttle...

Stofficer2 07-26-2011 09:10 AM

I drift my FB with the stock Nikki carb and have never seen my AFRs go past 12:1 under WOT. How did they manage to road race cars with carbs? Don't NASCAR drivers experience more than 1 Gs sometimes? They are carbed...

Alrx7 12-01-2011 01:33 PM

I run a webber IDA in my road race car (12a J bridge). I have never had any stumbling issues...even in the tightest tracks. It runs great.



However, I do like the EFI. Much more tunable with a standalone ECU than trying to work your way through the fuel jets, air jets and emulsion tubes of a IDA. I ran a Microtech on my old car...I loved the ability to look at a particular rpm and adjust. Instant results...more torque/hp. In any type of racing...power is king!


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