Dracula

Hello everyone, i have a 1406 edlebrock carb. I've been doing a lot of fixing up lately on my 1989. I changed the fuel filter and fixed a vacuum leak changed the header gaskets and got it solid, however at WOT it was going nowhere. I was reading up and saw that according to edelbrock the only way to change the WOT performance is too adjust the accelerator pump, the metering rods, step up springs and the jets.

To save my self some trouble early on i adjusted the accelerator pump to be (i think) a bit richer (moved it from the middle hole to the top hole) and WOT to my surprise was a little bit better still mehh tho. Everyone i heard said my engine seemed to be starving for gas but only at WOT. Inb4 edelbrock said it was only changable by making the car run richer at WOT and also inb4 calibration kit. So i went and bought one and left the stock jets in put new metering rods(1455) and put in the blue springs(3hg) it ran like crap and instantly starting idling with a grumble(i'd assume it's lean, but i guess it could be rich? not too much experience with this type of car stuff) at early-early mid throttle it bogs like crazy(seems like it's starving for gas) but once i punch it it would be fine. I tried with the 1455 rod and EVERY spring in the kit and it stayed the same the whole time. Tried messing with the timing and it did nothing.

Looking on the 1406 chart for edelbrock 1427(stock) jets and 1455 metering rod should be about 6% richer in both cruise and power mode. If this is true then why is my car grumbling at idle and starving for gas at low throttle? Yet with the stock calibration it didn't?

After a look at the 1405(i have electric choke so i'd assume it's not the carb i have) the 1427 and 1455 calibration is 3 stages lean on cruise and 1% rich on power mode. Could this be why my car is running insanely lean on cruise and the same it was before at WOT?

Again based on the assumption a grumbling sound/rough idle and the car completely shaking at low throttle is lean then it would mean i shouldn't follow the 1406 chart? Also i stood right by the tail pipe and it didn't smell like gas at all so there's no way it's running rich, correct? Also no smoke at all. So begs the question no gas smell, no smoke, no power how is it 6% richer than the stock unless the 1406 chart is wrong?

Thanks for reading

oil pan 4

iTrader: (1)

Get a wideband O2 gauge. Only way to know for sure.
What engine you have and your elevation are also very large factors.

Dracula

is there a place i can go to that will use it for me and i can just pay a couple bucks? spending $100 to check my A/F ratio seems a bit much.

I have a sbc 350(bored to a 355) and i live in long island new york, if that helps with elevation lmao.

it's running so rich that my plugs are fouled and gas is leaking into my oil. i changed the rods and front metering jets back to stoch. left the secondaries one size up and it's causing this. i'm assuming my secondary jets aren't closing at all it's just constantly feeding too much gas. it's too rich at idle with the screws all the way closed. it's even worst with them barely opened. i have to have my timing severely advanced to even drive it.

pancherj

What is your fuel pressure at the carb inlet?

Dracula

Tbh I havent checked yet, just got a vacuum gauge and fuel pressure gauge the other day and haven't got a chance to check it yet. It's mechanical pumped so I'd assume it can't be too high

pancherj

I know the Edelbrock carbs are sensitive to higher fuel pressure. I had one 25 years ago (never made that mistake again). I think they recommended 4-5 psi. Many mechanical pumps will put out more than that.

Dracula

Yea i had read about that recently, i went out to get a vacuum gauge and they had a vacuum/fuel pressure one so i grabbed it. I've just needed time where i have someone to crank for me.

I tried to vacuum test the carb and it had 15 in-hg, the downside tho is moving the idle screws didn't change my vacuum at all. I recently read that if the car isn't going into idle circuit it will just be constantly dumping gas since the throttle blades are open too much at idle and that the throttle blades being too open are what's causing it to stay in cruise/power mode.

I was using the idle screw to raise my rpm(didn't have vac advance and didn't know) because if i didn't it was horrible from stopping to going. I was having to run the idle at like 1100 because if i didn't there was a nasty deadspot.

I'm going to try in the morning to back the idle screw out and raise the rpm by advancing the timing a bit instead and then try and vacuum test the carb and test the fuel pressure. i'll see what happens.

This edelbrock carb has been a total nightmare tbh.

pancherj

Timing first, carb second. You need vacuum advance (or lock out the distributor at max mechanical advance) or it will not idle and the car will be very sluggish. Once you get that fixed, then start messing with carb. For now, the stock carb configuration should be fine.

Dracula

yea i installed a new vacuum advance in the distributor. i checked the fuel pressure it was at at least 10. i just got a fuel pressure regulator i'll see if it helps

edit: i just put it in, it seemed to help a bit but definitely isn't the pressure i'm setting the regulator too lmao. at very light throtle off of idle its giving a bit of black smoke but doesn't off of idle. also when in park if i very lighty touch the gas it sounds like a vacuum leak behind the temp control box. it's almost like a hissing noise, what could that be? the max vacuum i can get no matter what is 15. i have to check in drive to see the vacuum in drive. this might sound stupid but if i make the hose that the fuel is going through bigger or smaller will it help with lowering the fuel pressure?

lowering the regulator to 1 and turning the screws all the way in isn't killing the engine so it must still be getting a lot of fuel.

and also i cant time the engine until i fix the carb. close to tdc it stalls and shoots fuel out i would have to wing it by advancing it a lot, that's the only way it runs is at like 20 initial. i think i need even more tbh.

pancherj

Remember, fuel pressure doesn't feed fuel through the carb into the engine. The fuel is sucked in. Too much pressure can overwhelm the needle and seat and cause it to flood. If you set the pressure to 1 psi, the car would idle fine. Going WOT would be a different story. The bowl would run empty.

Check for vacuum leaks. If this is a Stock engine, 20 advance (with vacuum advance hooked up) doesn't seem unreasonable. Set the base timing with vacuum advance plugged and idle as low as possible. Then, hook up the vacuum advance and see where timing goes to.

Dracula

Ohh alright, i thought the fuel pressure being too high would force it in. i might try and lower the floats a little that might help maybe they're too high. ahh ok i understand.

I had a couple previously that i seemed to have fixed, we sprayed carb cleaner around the manifold and carb and stuff and it didn't change the idle.

It's a 350 bored over 5 with a pretty decent cam(not sure which exactly it is, it was installed previously)

i took it for a drive and it seems to be a bit better i still have to go into finding the step up spring size i need by measuring vac in drive but today was a run around.

the vac advance doesn't seem to change the idle too much so i'm not sure it's advancing much tbh but i can already tell vacuum drops a lot in drive before even checking it so i doubt it will much and no i'm talking 20 degrees advanced pre vacuum advance. below 10 pre vacuum advance was stalling my car

midias

Why did you install the 3hg springs? Measure the manifold vacuum and then put in the spring that is about 1/2 the measured vacuum.

pancherj

Depending on the size of the cam (overlap), it may require that much advance and only pull low vacuum. I am afraid I am out of ideas. I struggled with my Edelbrock for a short while and then tossed it in favor of a Holley and never looked back.

midias

What distributor are you running?
Are you using the timed or manifold vac port
What is your manifold vacuum with the distributor vac advance hooked up?
The best thing you can do is follow the manual step by step after you get the timing right

Dracula

It was a super coil but I changed the parts to a proform i think because the old coil went. My vacuum without it is about 16 with it is 15 at idle but the partial vacuum is pulling 7 at idle. These are in park tho not drive.

I only had the 3 in for a bit to test it i have 5 now. I have low ones in because again my vacuum definitely drops but idk exactly how much yet so I have the 5 in until I can check.

Currently I'm using manifold on the carb because I was told it would be a smoother idle if I did.

The problem is I can't exactly time it, again if I start to retard it twords tdc it stalls. So im assuming I can only time it by performance. A lot of people are saying you need a lot of advance for some cams.

Yea trust me I'm about to ditch it for a Holley too. If I can't get it to run right I might have too.

tartagliaz28

iTrader: (8)

i have the 1806 on my 355 and tuned it with my wideband. mine have 89 jets in both secondary and main 65-42 rods with the silver spring. my afr at idle is 15 and full throttle is around 13 to 13.5

skinny z

The first post reply and the last one (to this) suggested a wide band O2 gauge. It'll pay for itself in less than a season of driving with the improved fuel economy you'll be able to get. The WOT performance improvement will be a bonus.

Dracula

The problem is I'm pretty sure my cars computer isn't hooked up. Second someone is selling an af gauge but says no o2 sensor is included. How am I supposed to hook an o2 up to the gauge? Will the gauge read the o2 without needing the computer?

midias

https://www.amazon.com/gp/aw/d/B00N3VGPYS/ref=dp_ob_neva_mobile

Should be all you need

skinny z

The gauges are deigned to work with a typical O2 sensor. That is to say, the sensor will have a wiring connector on it that's standard OEM stuff. The gauge will have the counterpart to that connector.
I have the AEM gauge and have swapped the sensor (Bosch) for an over the counter replacement several times.

skinny z

Exactly. You run this independently of your computer.
Also, and I think you're asking this, the existing 02 sensor on your car should connect directly to the gauge (it may depend on the brand). You'd be wise to ask the seller to send you a picture of the harness' that comes with the gauge. There should be two. One for power and the other for the sensor.

midias

Don't use the factory O2 sensor get a good wide band sensor like the one I posted

skinny z

You're absolutely right. I hadn't thought about the factory sensor.
This does bring a question to mind though. Is not the standard replacement for the factory sensor the same Bosch unit as posted? Or an equivalent? (I know the latest generation of sensors are an improvement over what was available only a few years ago but still compatible.) I'm not sure seeing as I've never replaced a factory sensor on my Camaro. I removed the computer years ago when I swapped the V6 for a carbed V8.

midias

The Bosch unit posted is a wide band unit the factory unit is a narrow band unit. Completely different and not compatible everything is different in how the signals work. Narrow band gauges are junk and a waste of cash.

skinny z

I understand the differences. What I didn't know was what comes standard in an old Camaro. Now I do. And thanks.
And now the OP knows too.

Dracula

The problem is not the gauge the problem is idk what o2 sensor to put in neither the engine or exhaust system are stock

skinny z

Check out the link that midias provided. I think you'll find that the AEM gauge includes the sensor. What you'll need to do is weld in a bung in the exhaust.