'S'tuff1979

Hey everybody, im nearing the finish line now all interior is in, Most mechanical is down. Alls thats left is to bolt on the tires and adjust the carb????????? thats where im gonna be for the next 2 yrs im afraid if someone dosent have some answers here lol..... Is there any thing different or special for tuning the 1406 (600 cfm electric choke) or it is what it is deal? anyone have specific experience btw ive got a 350 engine bored 20 over thanks Joes

Rickman48

Set your timing, plug in a vacuum guage where you've the vacuum advance plugged in, and turn the adjustment screws on both sides until you get the highest vacuum reading!
When done, set the timing again, and do it again, making sure you're turning the screws in, to achieve highest vacuum.
Remove guage, plug in distributer, adjust idle speed, and you're done!!

Texas69

For basic tuning, search youtube for "edelbrock 1406". There is a multipart tutorial by PerformancePartscom that shows how to install and tune that carb. I know it is probably considered remedial for some (most?), but the visual was so much easier for me to understand how to adjust everything than the cryptic owners manual.

I also found that adding 1" phenolic spacer between the carb and manifold solved a fuel boiling issue.

coppercutlass

You might need a slightly bigger carb. if it's bored over it might not be enough., that is if you are racing if not the 1406 is fine on the street . i ran a 1405 straight out of the box on my low 13 sec sbo with little to no tunning. The 1405 is jetted richer than the 1406 and from what i have seen you cant calibrate the 1406 to run like the 1405 . I could be wrong but edelbrock has 2 diffrent tunning kits for the 1405 and 1406 . maybe internal restrictions. The 1406 should work good and be very close out of the box I ran a borrowed 1406 on my car for a month all i had to do was set the idle and it ran good.

Stevec

I put a 1406 on a stock 400 with headers and it was small swapped it for the 750 edelbrck and it's better.

cutlassefi

Racing or not, you're saying 5 more cubic inches from an overbore will necessitate a larger carb? I don't think so.
They have different kits because they start out with different jets and metering rods.
I'm told by Edelbrock that all the metering orifices in the 600's are the same, all 750's the same and so on.

coppercutlass

To me the 1406 didn't feel as strong as the 1405 I know 5 cubic inches isn't much but I felt the diffrence with my stock bore is all. Not saying the 5 extra inches will hamper it's performance or need more cfm. I was just sharing my experience. I tried a 1406 it ran good but not as good as i wanted ,i ran a 750 eddy which alot of guy said would work with a small block and it was a pig and bearly ran in box stock trim and a profomr 650 dp. The 1405 worked the best all around . I now have a holley 650 dp and its perfect. All these carbs where ran out the box with the exception of the proform 650 which i changed the throttle plates for a better idle. The 650 im running now is box stock out the box holley and the runs great. cutlassefi im just sharing my expriences never made claim that it "will" need it .

jpc647

copper, what is your setup?

I have a 1406 carb on a stock 350, hei ignition and 3.33 gears in the rear. Mine is problematic during the midrange. The motor seems to be getting plenty of fuel at high rpms and at low rpms. In the middle I can feel the car not pull as hard for a second or two. But at max rpm it's fine. The car will chirp second gear all day long(th350 trans), but sort of runs out in midrange.

A 1406 carb may very well be too small.

coppercutlass

The 1406 should work fine in a stock 350. It ran good when i had it mine with a big cam headers rpm intake 10 to 1 compression, 3.73 gears. I ran the 1406 for a month it was borrowed from a friend until i could buy my 1405. the diffrence between the 1406 and thye 1405 imo was throttle response the 1405 is jetted richer my engine needs fuel the 1406 choked it up. the 1405 ran good but the new holley 650 i got out does them all. The 1405 was enough to get me a 13.3 in the quarter mile . I also ran a 1405 on mild 350 with a preformer intake and towing cam and it worked great. I think you may have to tune yours you might have to change the step up springs or try a diffrent rod combo.

jpc647

I don't know if my engine is stock or not, it certainly isn't radical, but I can tell you it's substantially faster than a couple other 71-72 cutlass's in my area. But if you had an rpm intake, a high cam, and 3.73's I would think it should be find for my car.

I do feel in the midrange there is hesitation, and edelbrock says that's to be expected with the 1406 and a performer rpm intake. So I would assume your car had this problem too? I also has a hesitation from a hard acceleration from a dead stop, this is probably the accelerator pump, but I don't want to take the 1406 apart, rebuild it, and not be able to get rid of the mid range hesitation.

I've been contemplating getting a 1405 but it only comes with a manual choke, and my current 1406 has an electric choke. Don't know how to swap that over. The primaries in the 1405 are only 0.002" bigger than the 1406. Is that really going to make that much of a difference, to justify a new $250 carb? - That is a question, I really don't know.

Tony72Cutlass'S'

I have an edelbrock 1405 (i try my best to be old school with the manual choke).

It runs like a dream on my 350 Rocket. That's the main reason why i'm not putting on a properly tuned Q-Jet. I just really like the reliability of the edelbrock.

If your car doesn't start. dont hesitate to open up the top bowl of the carb and check the float height. IIRC it's 7/16''.

coppercutlass

My car ran fine with the 1406 no flat spots no hesitation just the power was not all there. I never had a flat spot or hesitation from a dead stop at w.o.t . The 1405 however did hesitate everynow and again depending on weather. That was my fault I never changed the pump shot setting but usually very minor. I have the 1405 I had on my car with a calibration kit. If you are intrested pm me.

jpc647

Do you have a stock motor? What are you running? Rear end ratio?

pm sent. what is a "pump shot setting".

Tony72Cutlass'S'

2.73 peg leg differential with a bone stock 350. Never been rebuilt (to my knowlegdge).

jpc647

Stock manifolds and everything?

Tony72Cutlass'S'

Yup, not to mention Single 2.5'' exhaust all the way to the back

I seriously need to upgrade my engine...

Mind you, i can roast my tire and smoke any IROC on the streets on montreal.

All in all, my car is built like a sherman tank, and i like it that way.

coppercutlass

The pump shot is the accelerator pump on the carburetor is has 3 settings you can use.

captjim

Every combination is different, not to mention environment. There is much more to PROPERLY tuning a carb than setting the idle mixture screws. See if this helps,
http://www.edelbrock.com/automotive_...ers_manual.pdf

coppercutlass

I agree with you jim. But imho I have ran 2 edelbrocks in the past. And they needed little to no major tuning. Just the fast idle and idle mixture and it was happy cruising even with my current combo a stock ebrock worked very well.

captjim

Obviously, if it runs fine, no need to get into it. But, I like to tune, it is part of the fun for me. While most carbs will run OK out of the box, there is usually some performance to be found in fine tuning an engine, both carb and ignition.

jpc647

This is surprising to me. Now I have 3.33 gears in the rear, the performer RPM intake and 1406 carb and I wouldn't confidently say I can take on an IROC. I've never driven in one though. Maybe they are not as fast as I would imagine. Or maybe my Oldsmobile is faster than I think it is. I can only compare it my my DD, which I don't consider a "fast car", but it'll hold it's own.

I can't seem to roast my tires though. But my car will chirp second gear. I definitely need a new accelerator pump, I'm pretty sure mine is on the hop notch, so the diaphragm must be torn.

Tony72Cutlass'S'

Hmm interesting, it also might be because the kids out here in Canada drive cars for looks rather than for performance. Unfortunately all the unibodies up here rust out and there are barely any cars left from the 80's.

My car had a TUN of rust, but it was in "fair" condition for our northern salene climate.

jpc647

Just for my own curiosity, when you say " I can roast my tire" do you mean if you are stopped, and you let of the brake and floor the accelerator you're rear tire will break lose?

I only ask, because i've tinkered and tinkered with my car, and I'm not seeing anything wrong. I'm starting to wonder if maybe it's not a hesitation, but maybe just the car doesn't have as much power until it winds up a tiny bit.