Webers leaking

[ChrisZ]

Dave, it looks to me as you have your FPR on the hose feeding carb one and two and then no FPR on carb 3, is that right ?

If you put 7 psi on the third carb, your needle valve might leak, if the mechanican pump is on, you can just cut the Mr. Gasked off and give it a try.

What engine have this setup, i think 28 chokes sounds a bit to small, i'm running 30 and will swap them to 32 soon.

Chris

[Zs-ondabrain]

The FPR is over by the fuel pump and fuel filter. What you're seeing is the FPG (gauge) to show me the amount of fuel pressure to make sure I'm not over doing it.

28's are too small but I have 30's on the way as we speak.

But my main concern or question is the studdering. what would cause this. Sounds like a lopy Cam but it's not.

Dave

[ChrisZ]

Oh, didn't see that, the only experience i heve had with studdering was due to worn throttle shafts, but that was on a single carb with only one barrel.

Have you read the Weber and Dellorto book ?

[yetterben]

ugh...Full of fail. The pics are jet well gasket idle return spring banjo fitting crush washer and gasket. O rings are for the progression port screws.

[yetterben]

The carbs will never see any higher than the reg pressure. Needles only see that high pressure for 1/10th of a second wile the system is primed. For a fact the stock 2.0 needles can take 9 psi before they blow buy.

I am not trying to be rude but i have never seen such misinformation about webers until i started reading this site again. I guess if people like playing guessing games and shotgunning parts buy all means. For a informative thread about webers with informed decisions and engineering like precision look in the l6 section sticky's at Hyrbirdz.

I just cant stress enough wideband dyno time etc etc thought process informative decisions etc.....

[yetterben]

Just got the 40DCOE's up and running better this week. BIG Thanks to YetterBen in WI. He rocks.

I used the stock dual fual rail outlets, #1 feeding the front 2 and #2 feeding the rear. Mr. Gasket 7psiI fuel pump at the rear, regulated by a Spectre Fuel Regulator at 4psi. and backed by a stock fuel pump.

Spectre S.S. hose braiding kit and Fuel pressure guage (cute little thang ain't it?)

Got serious idle and running issues though. Studdering like and idle jet (1 or 2 of 6) is clogged or barely pissing in the hole. From idle to 4Krpm and nuetral pedal (not accelerating or decelerating) has a jolting effect, like I'm tapping the gas pedal every other second.

140 mains

200 Air correctors

4.5 Aux Vent, 2 new ones for obvious reasons.

28 Chokes

idle screws at about 1/2 to 3/4 turns out from closed

throttle screws at about 1/2 turn out.

Any thoughts? Please!!

Thanks in advance,

Dave.

I got lots of thoughts dave most to racey for this site i am sure. Give me a call.

[yetterben]

I will also add that dial restrictors are trash and belong in the trash. never ever ever ever ever trust your car to a dial regulator EVER!!!!!!!!!!

People if you want informed help you need to come prepared. All jet sizes posted float setting posting bleed back posted needles posted. E-tubes all of it right it down. For god sakes open your carbs and make sure they all match. 30 years of dumb american back woods mechanics ****ing with $^!# thinking its a Holley.

Make sure your fuel system is on order no cheap junk you want cheap junk run the stock crap. You put webers or mikunis or sk's or whatever on your car for performance. Dont talk about gas mileage who cares is that why you got triples? For MPG or for wot balls to the wall make your neighbors crap sound.

Nissan Race sector used mikunis for a reason....??? Wonder why they didnt use hogged out su's?

So many people screw up or have no clue blame the carbs or over carb there setup. Its not the carbs fault its dumb previous owners or dumb people passing bad info around.

I will take a set of triples over Su's anyday and can out perform SU's in every way, even mpg. Its all about what yah know what your willing to learn and having some sense and R&d like dyno time, Wideband etc. If yah cant afford it run SU'S

Now that the rant is over my disclaimer. This was not directed at anybody. Its a general notion that needs to be followed for informed answers.

If you dont know the answer dont post why waste peoples time. People want informed help. Not i think or maybe or try this.

Edited May 18, 2010 by yetterben

[yetterben]

Oh yeah regulators always belong on the return line never the feed line. Dont wanna listen or believe not my pistons that will melt when a carb runs dry.

[Zs-ondabrain]

Well said and no offence taken Ben. You've been a great help when no others could. Guessing isn't helping my situation. I'll check the bottom for plugs and get you those idle jet numbers.

Did those 30's make it in the mail? Forgot to ask when I was on the phone with ya. I'll be in the garage for a bit and will text you the numbers asap.

I don't understand how the regulator regulates on the return. SHouldn't it do it's job before the carbs? Weird.

Thanks again, I'll also spend my off time reading my Weber book and follow that with a little L6 forum reading at HybridZ.

Dave

Edited May 18, 2010 by Zs-ondabrain

[yetterben]

They went out yesterday Dave. I found the 5th you need 1. Webers are the hardest to tune out of any triple setup. Why? becasue no other carb besides Dell's have as many variables. Mikunis where oem carbs solex the same. Sk was a rip off of mikuni. Most of the time you can remove the sk jet cover sticker and see Mikuni stamped on it.

Dont rule out small cracks in the soder joins on brass floats for front leakage. they can sink just enough to cause the carbs to drip at idle. Plastic floats can only handle 18psi of boost before they crack. Ask me how i know. I ran 18psi via a t3/t4oe via my webers tuned them in perfect. Laid down 368hp with them at 15psi.

Going efi now cause the webers cant offer anymore what i need.

Edited May 18, 2010 by yetterben

[Mikez73]

Well said and no offence taken Ben. You've been a great help when no others could. Guessing isn't helping my situation. I'll check the bottom for plugs and get you those idle jet numbers.

Did those 30's make it in the mail? Forgot to ask when I was on the phone with ya. I'll be in the garage for a bit and will text you the numbers asap.

I don't understand how the regulator regulates on the return. SHouldn't it do it's job before the carbs? Weird.

Thanks again, I'll also spend my off time reading my Weber book and follow that with a little L6 forum reading at HybridZ.

Dave

My only experience is with EFI cars which always have a return line and yes the FPR should be on the return line. A good FPR for EFI will always have a return port. How it works (IMHO):

Picture a garden hose on at full flow with an open end. The water flows out the end of the hose at whatever pressure water lines have. Now if you cap the end, pressure builds up in the line. Now poke 6 small holes in the hose (those are your injectors). It starts spraying water out of those holes because of the high pressure. Now say it is just spraying WAY too much but, you know if you turn off the water that it wont spray anything thing. If this is the case (as with a fuel pump) the only way to regulate it is to make a small opening in the end of the hose (this is your FPR) to relieve SOME but not all of the pressure. All you do is keep making the hole in the end of the hose larger until the pressure in the hose is regulated to what you want.

I guess the same would apply for carbs. I don't have a return line though :disappoin

[yetterben]

Thats about it. Reason being it should never be on the feed line is you cant guarantee everything in the row is seeing that fuel because you are reg it before it gets there. On the back end you know fuel had to flow to everything to get to the reg right........Food for thought.

Dialregs are bad cause they open a small orifice to reg pressure but cripple flow vs a diaphragm and spring regulator.

Edited May 18, 2010 by yetterben