help setting up carb....???

[kimcrwbr1]

On my choke I found adjusting it to where it just pulls it all the way open after the ignition is on for about 3 or 4 minutes or until the intake manifold gets warm enough to preheat the fuel going in. Just keep turning it slowly to the rich position and time it to be fully open when the engine is like 3/4 the way up to temp.

 

[ford1386]

I set idle air screws and put one new spark plug in cyl 1 and I'm gonna check color after I drive it for 50 miles and set jets accordingly....

 

[ford1386]

What is the correct way to read spark plug color, holley said I want a light toasty brown. But is that on the porcelain or the base ring. And can I just check them after I drove it 50 miles the other nite or do I need to drive it then shut the key off at 65 and check on the side of the road?

 

[kimcrwbr1]

I would say any time would be good after 50 miles. How is it running does it set you back in your seat and keep you there. Probably the best way is to use a sniffer for emissions but not practical in most cases unless you have access to one. Your carb came with .65 primary .68 secondary and .031 discharge nozzle from the factory for your engine stock. Start there your 30 over on the bore so maybe a couple over so your not running too lean.

 

[1mean02hd]

The porcelain insulator should be a light brown. Have you checked you firing order on the cap? Needs to be 1-3-7-2-6-5-4-8 with an HO/ roller cam. I run an MSD distributor and an MSD 6AL in my 94 as well. I also run a Demon 650 vac. secondary carb. A little overkill, but it runs great so I'm not gonna change it. I think my total timing is about 34-36 degrees at 3000 rpm. Also turn all idle screws all the way in and use a vaccuum gauge and back each out a 1/4 turn at a time until it idles correctly and you achieve the most vaccuum at idle. (Idle should be 800-1000 rpms) It's better to set total timing with the MSD distributor to take the full effect of the springs. Also what balancer are you using? My Professional Products piece has several sets of numbers on it and was a little confusing until I figured out what set I needed.

 

[ford1386]

I'm running stock balancer

 

[1mean02hd]

Set the total timing for the mechanical advance. It's a more accurate setting than the initial timing. There's no way to really lock the timing advance out to set the initial timing like a TFI distibutor does.

 

[kimcrwbr1]

I believe he has his set at 35 at 37 it pings. What spring are you using for the advance and his engine is bored 30 over with a stock cam do you know the correct jets for a holly 670 street avenger I believe it came with .65 for the primary and .68 for the secondary and .031 for the discharge nozzles. Hopefully he has got it dialed in I have been thinking about doing a conversion on my 83 2.8 to the 5.0 2wd AOD with a nice hitch and pos third member. That way I dont have to mess with emissions being over 25yrs old and I just like the 1st gen look.

 

[ford1386]

I checked the one new spark plug that I had put in before my 50 mile drive. And the porcelain has no color at all its like brand new, but the last thread on the plug is black and the electrode is black, but there is no color on the porcelain..............

 

[kimcrwbr1]

Did you pull one of the other plugs. I think your running lean do you know the jet size for your primaries. You need to be careful running it lean you can burn valves or pistons. Someone else should chime in.

 

[1mean02hd]

Yeah white porcelain is lean. I'm not too sure what jets are in my carb but I know my primaries are perfect and the secondaries are a tad on the rich side (I smell gas while running the piss out of it), but like I said- it runs great I'm not messing with it. IIRC I am running the stiffer springs on my advance. It's been a while since I checked. I would go up 2 sizes on the jets on the primaries and drive it without opening the secondaries and check the plugs again. Make sure to set the timing where it won't ping. If the plugs are a light tan color (which is what you want), proceed to go for another drive and run it to open the secondaries. Rich, you'll smell gas; lean, it'll fall on it's ass; stoichimetric- it'll haul ass. Then proceed to advance the timing to your wants. You might also want to change plugs between the primary and secondary tuning sessions.

 

[ford1386]

I had jetted to an 80 in the primaries once to just see if the stumble I had was any better and I checxked plugs after driving 2 miles and still didn't see any color change. There is write ups online saying that with unleaded fuel you won't notice a color change how long do I have to drive it to see a change?

 

[baddad457]

I checked the one new spark plug that I had put in before my 50 mile drive. And the porcelain has no color at all its like brand new, but the last thread on the plug is black and the electrode is black, but there is no color on the porcelain..............

The 4 year old plugs in my Ranger look like that. Mixture is as perfect as you can get. Starts at 25*F without a choke (I removed all traces of it) idles without it too. Does it have a cold stumble ? Yea. But that goes away once it warms up.

 

[ford1386]

Mine is thr same way so should I just drive it or what but I don't want to screw my motor up

 

[NITRISGTO]

your jetting

when your truck is cold blooded it is because it i lean
if it stumbles it is lean if it surges at 40mph or 50nph it is lean
if it has a vacum leak it will stumble also but generaly the idle goes up and will not want to idle -- if it has even just a lose clamp or a tiny hole in the supply fuel line from the fuel tank to the fuel pump it will suck air and run lean and will not get you 4.5 psi to maximize power --plus it will empty the fuel systym overnight or a couple nights making it crank and crank till you pump fuel from the tank again--- when changing jets you need to look at the book not all jets change the way you think ----- 69 might have a 69.000 hole but a 68 has a 66.000 hole their is a little fudge in their most jet changes need to be at least 5000 in hole size to feel a difference 10000 can be to much --- jets make it idle crispy lumpy lazy or healthy in the bottom end under 6000 rpm ? when the jets and floats are right it should not need a choke at all till it gets real cold ---cold blooded would be to lean --- starts right up buut lazy and loud but no power and no top end ---to rich -sticky choke to much fuel pressure . pluged exhaust kills top end also -- squirters are of idle transition larger holes for lumpy low vacume engines but float levels also afect mixture lean is low floats ----rich if it is to high or overflow
MOST IMPORTANT their are 2 air bleed holes in each throat of the holley carb making 4 in primarys and 4 in secondarys they need to be blown out with carb cleaner often any spec of debri in the small holes will make drivability issues
wish you luck hope this helps make it a screamer