Hello

I am running lean up top, 6000rpm 351w--2100

What size can I open the fuel inlet to?
Number of drill?

Paul

For Optimal Race Domination

We really need to let everyone know that, and that this is not on a street car.
I am not sure that doing this will help your situation.
What jetting are you running for your carb? You are oval racing right? On a 3/8ths track correct?
So when are you hitting 6 grand?
I understand the want and need to get a couple more hundred rpm in the last stretch but if that bogs you coming out of the corner, its one of those prime examples of losing time by being faster.

If you really are looking for some more, and without knowing what jetting you are running, I would say to bump the jetting up one or two.

To drill out the fuel inlet, would be a mistake, then the needle would not be able to close off the fuel supply, and you are still regulated by the jetting anyway, all you could concievabley do by doing that would be to fill the bowl faster and possibly overfill the bowl, the next step would be a nice fire going down the backstretch or if you did it right down the frontstretch (the promoter will love ya after all the rule of thumb is if you are going to wreck big do it going down the frontstretch so all the fans have something to cheer about)

Bill White
White Automotive

Hello Bill

COOL! the fire that is! lol lol

MY car is a street stock that I race on a 1/2mile asphalt oval. Correct
Trailer only car!

I am running lean. Hit 240* untill a caution.

Yes I think I need to fill the fuel bowl faster.
I an using 75 holley style in a 1.23 C3 2100 carb.(I can get entire number)
No choke plate, But entire horn.(rule)
I know the 75's are too fat!

Going to change power valve to 4.5 holley
down the jets to 73's
And maybe open the fuel inlet. your the better judge.
Float is high.

Paul

For Optimal Race Domination

We run a 1.23 carb on a 351C, also no choke or plate and I have removed some of the airhorn (but on the motorcrafts you actually loose airflow if its all gone (or at least we did).

I run C8T carbs since we are running a 68 cougar and C8's are 1968 carbs. The inside of our carbs have to be bone stock and for the most part ours are, and I am only running 1 jet size over stock. Even with a free breathing cleveland we rarely hit 6000 on the 3/8ths (only ocassionaly when we are racing hard) Usually our tattletale is around 56-5800.
We visit a 5/8th track and we run a little bit different set-up since we want that cleveland to breathe (and it does) so since we are running up to the upper 7's on the bigger track, I don't want to be caught going lean. On those carbs I break my own rules and go 3 to 4 jets larger.

I run the stock fuel float level and have no problem filling that single bowl with our mechanical pump EVER, no matter what track we are running.

If you follow this forum, you all know I am a HUGE proponent of running stock to maintain the equilibrium that is built into ALL CARBURETORS. Once you start drilling, hacking or willey-nilly changing things, that then leads you down the slippery slope where you are constantly doing "fixes" to correct the equilibrium that has been thrown off.
Haven't mentioned this is a long time but that is why I am involved in this forum. I have seen too many carburetors that have been wacked out and have all the latest gizmos and "hop-up tips" from the local speed shop and teen car magazines.

Best results come from establishing a consistent base-line, which for a single car racing program means 3-6 EXACT same carburetorsall built IDENTICAL with factory settings. Make sure each carb is set and DELIVERS THE SAME RESULTS. I dyno AND time test ON THE TRACK each carb in our program (and yes if you don't consider your single car a program then you can stop reading here).
Then take one carb and use it as a test mule to change settings and see if the results DELIVER the expected time inprovment. ONLY CHANGE ONE THING AT A TIME. NEVER CHANGE SOMETHING, TO MAKE ANOTHER CHANGE THAT DID NOT IMPROVE SOMETHING YOU THOUGHT IT WOULD. And document everything.
After a while you will know what works and what doesn't and you will have documentation.

I can tell you a big hint, most people look for more horsepower and more RPM going down the straight and into the corner. You will be further ahead by working on trying to get out of the corner faster.

I would not drill out the inlet, I can't imagine a 2100 not being able to get the bowl filled adequatley and being able to keep it filled.

Bill White
White Automotive

Hello Bill

This is why I come here. For Good information!

I am going to change the power valve to the 4.5 Holley
New fuel filter.
Drop down to 73 Holley jets
check the float & vent.
New carb stud!( came off in the heat race. Hit gas out of 2 an no go!
Engine was still running oops lol)

I still have the fuel inlet that came with the Carb.
I did not change to the one in the kit.

What do you do with the needle air bleeds?
Mine are 2 turns out. didn't put a vacumn gauge on it.

Hey on the big track do you change the timing?
I run a Dura Spark II @ 33* I think.

Paul

For Optimal Race Domination

Hello All

This is my car


Paul

For Optimal Race Domination

So here goes:
Lets clear up the last post, You did not replace your needle and seat when you rebuilt your carb?? Is the "seat" what you are calling the "fuel inlet"?? REPLACE IT NOW, and make sure it is the "window" type, problem solved and now you do not have to drill it. (you did use a motorcraft kit right???)

Next, LOCKWIRE, embrace it, use it!!!! More deaths have been caused in racing from carb linkage coming off or breaking than from anything else happening. This often overlooked area, gets so much abuse and wear. Imagine you come out of the corner, mash the throttle and scream down the back stretch, passing 4 cars ahead of you, you lift only to find the accelerator is still bottomed out to the floor. DO YOU MAKE THE CORNER, OR DO YOU CRASH FULL SPEED INTO THE WALL AND DIE!!! LOCKWIRE, EMBRACE IT, USE IT!!!!!! IF YOU CAN'T RACE SAFELY......THEN DON'T RACE!!!!!!
You got lucky, your guardian angel gave you a mulligan, others have not been as lucky as you. Go buy a lottery ticket TODAY, Donate a large sum of money to your favorite charity AND LOCKWIRE YOUR *&^&*%) THROTTLE CABLE....TODAY!!!!!!!!!
(Oh and along the same lines, don't use a carb stud (no way to lockwire one half of it) use a heim joint fitting and a solid mounting point which can then be lockwired on both sides. (Yes its more expensive but re-read this paragraph again)

VACUUM GAUGE, embrace it, use it!!!! If you are not using a vacuum gauge to set your idle mixture screws, well,...your not setting your idle mixture screws. (You don't race with blinders on do you? Just wondering............)

Power valve? All I am going to say is: "What is your basis for replacing it????" If you don't know why or have a way to measure the results then you are shooting in the dark at shadows. This is (believe it or not) advanced stuff (shouldn't be, but in my racing experience have only seen a very small amount of people doing this type of testing)so you need to know where you are headed and what direction you want to go.


We run the duraspark as well (stock ignition), but yes for the bigger track we change many things, including timing. Its the difference between wanting to run efficiently at 4000-5600 and running at 5000-7600. The bigger track makes a huge difference in how we tune and set-up versus the track we always run at. We carry much more speed through the bigger corners, and that changes what we do one the straights.

AGAIN KNOW WHERE YOU ARE GOING AND WHAT YOU WANT TO DO AND THAT WILL DICTATE THE CHANGE(S) YOU NEED TO MAKE. KEEP A LOG AND DOCUMENT ALL CHANGES. MAKE SURE ALL CHANGES YOU DO TO YOUR CAR ARE BASED ON PROPER TESTING AND MORE INPORTANTLY, RESULTS.
NEVER MAKE A PERMANENT CHANGE FOR A RACE WITHOUT TESTING, SEEING AND DOCUMENTING THE RESULT.

Now go lockwire that throttle cable.......

Bill White
White Automotive

Hello Bill

Yes extra springs are required in our cars for just this purpose.
I was on the outside stayed high. & idled around to the pit. Lucky

OK I will change the Fuel inlet
I have the power valve from the kit in now.

I will have my buddy over to wire the throddle. He works on Airplanes.
They wire everything!!

Paul

For Optimal Race Domination

Hello

well I got the Fuel inlet in.

The old one only had 2 holes. The replacement has 4 holes, No windows.
The one from the kit had No holes.

Dropped jets from 74 to 73 (Holley style)

New throddle in.

Upped the timing a touch.

Paul

For Optimal Race Domination