FAQ - Carbs

[2L Bunny]

Quote, originally posted by OnTheRunDCI »

Running a 2L 16V with dual weber 45's and have the carter pump. Which fuel filter should I run? I've heard of a 3 port filter than I can run the nipple on the tank that was for the return line to instead of capping off that nipple.

I use a ~'89 Maxima fuel filter. It has 5/16 (8mm) nipples on both sides.

[Cynical 1]

Quote, originally posted by mofoco »

what about blockin off the frigin injectors how to?

cheap and dirty - use dimes and some high temp silicone in each injector port.

or, go buy 4 trans drain plugs from the dealer and screw them in.

[Mike Ngo]

[6thGearGLIGuy]

I got a couple questions about my carb set up

-the carter 4070 pump i got didnt come with any wire harness, where can i get some wires that will hook up to the terminals on the pump?

-I plan on running new fuel lines what size should i go?

-I wanna run a fpr, how much pressure is good for dellorto 40s?

Thanks very the help

[the12for12]

Concerning Flat Slide Motorcycle carbs

......to be continued

Quote, originally posted by Jeprli »

Flat slide main jets only come into action at top quarter of throttle, midrange is controlled by the size and position of needle(you move a clip on the needle to a different position, upwards leaner, downwards richer, it basically controls when the main jet will kick in) and for first half of throttle it's all in the a/f mixture screw. If engine is running too rich with these carbs, it will bog down at lets say 4000rpm, if it's too lean it will let you know a lot sooner as it will have hard time starting. These type of carbs use very low fuel pressure as most are gravity fed so don't go crazy with pressure 2-3 psi the most. Oh and there is the float bowl which has a fork that controls these floats, you can bend that tab and allow more fuel into the bowl, but that is only for those who really know what they're doing. Also adding a little bit of high quality 2 stroke oil as a premix to your tank will keep flatslides smooth , and keep them from seizing(16:1-10:1 premix ratio). Balance and lighten your engines when using these as they rev up a lot quicker than fuel injected motor. These are practically impossible to synchronize, so the best you can do is have each one set exactly the same. I'll be doing this for my winter project, using a 2l aba motor with most probably yamaha R1 slides.

All additional info IM the original quoter, Udig?

[chopWet]

yep we need more on bike carbs, I have two magazine articles that give an overview of the conversion, if someone could host them they could be put up for refrence....

[Jeprli]

As for that premix ratio, use between 75:1 - 100:1. I made a mistake, sorry.

[the12for12]

Quote, originally posted by chopWet »

yep we need more on bike carbs, I have two magazine articles that give an overview of the conversion, if someone could host them they could be put up for refrence....

[Big CADDY]

wiring in a 8980 timing computer and a 6A or 6AL. using a VW ICM\

Modified by Big CADDY at 10:14 PM 1-29-2009

[bradford_ramage]

i have a 2L 8v counterflow (rv head) im gonna run sidedraft from a cbr 900rr any extra info would be wasome thanks my only main concern now is my ignition comes from my digifant box and i need to know how im gonna get my spark these setups appear to be for a cis or cis-e box help on ignition


Modified by bradford_ramage at 8:44 PM 9-21-2007

[GermanRob]

okay, lets take this to the top with some real crazy idea's
I have recently acquired a mk2 8v along with a dual 40mm mukini carb setup and cam.... I really want to run nitrous with that setup and don't even know where to start.
12for12
I'm gonna need ur help on the carb side of this from A to Z, its gonna be rather ground breaking and a spare 8v motor has been donated for the cause to see what this will produce. I have some help from experienced tech's awaiting the neccessary info to install the carb setup. Just lay it out here for them and we'll be testing the nitrous grounds shortly there after.

Yes I said nitrous, everyone can keep their negative comments to themselves.


Modified by GermanRob at 11:22 PM 10-10-2007

[Big CADDY]

I too have a nitrous setup I was thinking of putting on mine.

[jetta1986]

hey guys does any one here know how to tune a set of Dellorto 40mm carbs ive got em on a 2.0 x flow it rips all the way till 4th gear and after that it wants to almost die out

[ANDYCABBYRH]

can the car run with the stock bosh coil, dizzy and no msd or ICM?

[Big CADDY]

no. but wiring in a ICM is simple.

[DriVeWaY2L16V]

I have a 92 16v gti. And a pair of 45dcoe's, now since i have no ignition control unit. Can i just use a MSD6AL with my factory computer and Dizzy? Or will this not work? And what size fuel line are you using from the pump to the front?


Modified by DriVeWaY2L16V at 1:49 AM 1-11-2008

[Big CADDY]

you can use one of the existing lines for fuel, swap out fuel pumps, run a regulator and filter and your good to go. no return needed with 4psi

use the factory dizzy and a MSD 6A or 6AL. you can add the 8990 timing computer for more advance also. the diagrams are above. The ignition control units are a dime a dozen in junk yards.

[DriVeWaY2L16V]

Do i need to wire the Hal sender on the ICM to the one on my Dizzy or anything ? Or do i just add the ICM and i'm good.

[Big CADDY]

just use the wiring diagram above. pretty simple.

[ANDYCABBYRH]

does the ICM need to be ground it it self to the body or could it be mounted anywere? (it's usually mounted on that alum bracket to a metal bracket)

[Mk2enthusiast]

no mounted anywhere, the metal base carries no current

[Big CADDY]

It was also designed as a heat sink I think.

[C LePoudre]

Stock coolant flange is interfering. Couple of cryptic things on the FAQ about this but I didn't see anything concrete. One mentioned ABF flange, another got a coolant flange from "Pierce". Any advice?

Also, I'm assuming that if I move the alternator down to the AC mount that this will solve the interference issues...am I correct?

[ANDYCABBYRH]

my vw ICM numbers go in or 1-7 not like the one shown in the picture above:
Pins
#1 green wire
#2 brown
#3 brown/white
#4 blk
#5 red/blk
#6 green/white
#7 empty

I'm using a 6AL+msd blaster coil+vw ICM but I need to wiring help. (16v with webers).

[ANDYCABBYRH]

never mind I got it figure out

Thanks anyhow

[Big CADDY]

I need to correct it in the diagram. I have many people question about that. the ICM or plug has the pin outs on it. My illustration was designed to just go by the numbers, not the order. Just laid out to keep order and not have wires crossing wires to confuse more.


Modified by Big CADDY at 5:49 PM 1-29-2008

[dave y]

I have an old ITC Scirocco 1.6 race car that came with a Weber 32/36 DFV carb. The engine would miss and cut out on right hand turns. It was a little rigged up so I bought a used DGV, rebuilt it and installed it. Then I had the same problem on Left handers. Tried all different kind of float level changes and couldn't correct it.
I picked up a Haynes/Weber manual and started to read from the beginning. In the instalation recommedations it states that the float bowl should face forward and the throlle plate shaft parralel with the crank shaft. This configuration is only possiable with the DFT. Early catalogs showed the kit from Weber used the 32 DFT but later aftermarket suppliers only show the 32/36 DFV.
Was there a design change to make the DFV suitable with a side mount float bowl? I have been able to locate good used DFT. Would that work better for a racing application under hard cornering? I'm afraid the 32 mm primary and secondary might be too small.
Just a couple more notes. I have dual fuel pumps and filters. The engine is highly modified to SCCA H/Production class limits. With the 9 inch wide slicks, it generates tremendious cornering forces. Keep in mind, I am only allowed a single down draft carb on a stock but ported manifold.

Dave Y.

[dubbass33]

about how long would i take for a few people working together to put ITB's on a 16v?

[nolangherity]

im trying to do a carb setup on my 1.7 liter 8 valve.

i was contemplating three setups.

1. set of 40mm motorcycle carbs.
2. a weber 32/36 down draft
3. a single weber 45

the car would likely just have a lightly port/ polished head (DIY) and a 288 TT cam with the heavier duty valve springs.

i dont want to "under carb" the car. id like it to flow free as possible. anyone have any input of what would work for this setup?

thanks

[elias]

does the icm wired with the msd accomadate for the ignition advance? making big caddy's wiring diagram the only thing needed for wiring the ignition?

sorry if i missed worded anything im half awake

[Big CADDY]

The only advance with the MSD setup is a static advance set at the distributor. the timing computer doesn't advance the timing. it retards the signal 20* at idle and decreases the retard amount to 0* at 3000rpm. So if you want a 28* advance at 3000rpm+ you set your static timing to 8* at idle then as the motor revs to 3000rpms the timing computer will reduce the retarded timing bringing your timing to 28*.

I think I had to type that out so I could understand it..

What's listed in the diagram is everything you need and the proper wiring for it. remember that I haven't put all the wires from the ICM in order. don't go by the order. go by the numbers.

I hope this helps ya out.

[nopaddle]

I have a 45 dellorto sideraft carb for sale, the carb is in great shape and very clean, comes with a new chrome air cleaner and filter that never got around to being used.... $300

[euro mk2]

i hve just done a 16v conversion on webbers. we cant get it to fire up tho
we have fuel, a spark and everything is in time... is it necesary to have an msd or is there another way round it?

[Big CADDY]

you can eliminate the MSD and use just the icm,

I have a setup like that that I carry in my glove box so if anything happens, I just swap it out. You need to be careful of your timing advance then since there is no change to it.

Without a bentley I am pretty sure wire 1 on the ICM would go to the Positive on the coil

[elias]

what is the best way to "incorporate" the icm to that harness? should i use the female part that plugs onto it or just soilder the wires directly to it?