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Old 07-29-2003, 09:32 PM   #1
Senor_paco
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Edelbrock #1407 carb jets/rods help please

Hello again, I've started playing with my Edelbrock 1407 to get the secondaries to work properly, and am on the right track, but need a little guidance fro mthose of you in the know. First of all, whenever I stomped on it, it would just bog out. Then I bought some step up springs, and replaced the orange 5" springs with the pink 7" springs. well, now we have something but it sputters a lot. Okay, then I put in the silver 8" springs. Now we are going good to about 75-80% WOT, then it starts to bog. I'm thinking I need to go with richer jets, maybe 2 stages as per Edelbrocks' site, but wanna make sure I'm going the right way. I'm thinking since the spring is weaker, it opens under higher vacuum, feeding more fuel, so if I go richer, it'll give me more fuel and also by replacing the rod 2 stages richer, it won't affect my cruise mode, since that's currently ok, with the plugs being a light tan. I don't wanna replace my jets if I can help it. THe rods are right on top and take maybe 2 minutes to swap. A heck of a lot easier than my old Holley carbs. My Ex said she could hear me stomping on it almost 3 blocks away!

Am I right on the rods issue?
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Old 07-29-2003, 09:37 PM   #2
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Oh yeah, btw 350, .060 over, Crane 272 cam, Edelbrock Performer RPM manifold, Flowtech headers, Supercoil HEI, yada yada yada...


Must... Go... Faster... (jurassic park)
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Old 07-29-2003, 09:46 PM   #3
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You may want to run bigger secondary jets. Changing the jets isn't very much harden than changine the metering rods, just pull the top off of the carb. I changed the secondary jets in my 1406 from .095" to .098" jets, and it took me less than 20 minutes, and gave the truck more of a "kick" when the secondaries open.

If you say the truck runs great under part throttle, but is lean when the secondaries are open, try maybe some .101" jets in the secondaries. I tried them in my 1406, and they were too rich for my combo and actually slowed the truck down. They may work for yours. Have someone look behind your truck when you mash open the secondaries....if alot of black smoke comes out the exhaust, you are proably already running too rich. A little black smoke is normal on a carbed vehicle, but not too much.
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Old 07-29-2003, 09:49 PM   #4
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Stiffer springs put the rods into power(rich) quicker. on my 383, I run the stock 113 jets on the primary side, with a 73/47 rod....just a touch leaner on the cruise mode than the 71/47s out of the box. secondaries are box stock jetting, & the step up springs are orange(5 hg). The acc pump has been set down a couple holes, for a little less pump shot. Out of the box, my 1407 had a float level off, causing it to run rich......I would pull the top, & check/set float levels as a 1st step. The jetting is for my 383, specs in the sig. Good luck,crazyL
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Old 07-29-2003, 10:52 PM   #5
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crazylonghorn,
Help me understand something you said. To get a leaner shot from the acc, pump you moved the rod down closer to the manifold? I have a 383 stroker also with a very high vacuum signal. Whats the best way to determine which springs you need for the metering rods? Thanks for your help.
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Old 07-29-2003, 11:17 PM   #6
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Take a look at the holes in the pump arm, & as the link rod moves closer to the carb body by swapping holes, it should raise the acc pump up in the carb to give a bigger shot & vice versa. As the link rod is moved away from the carb the acc pump sits lower in the carb. As far as the step up springs, my 383 seems to work best with the stock orange springs, & does pull pretty good vacumn(16.5" @ idle). From what I gather from edelbrocks tuning info, a flat spot in the powerband that cant be tuned by jetting, can sometimes be "cleaned up " by swapping the stepup springs. The only way I know , is to swap the springs, & test run.Orange are 5 hg, Pink are 7 hg, & silver are 8hg. the yellow & blue springs are 3 & 4 hg, & more used for low vac situation with a large cam.You can get the spring kit separetly, or in a tuning kit with jets & rods. Edelbrock 's site has a lot of good tuning info on the carb . Good luck,crazyL
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Old 07-30-2003, 12:29 AM   #7
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yellow72, the primary on mine is .113, and the secondary is .107 stock. your 1406 has .98 and .95 respectively, at least as per Edelbrocks web site. I saw where you replaced your springs, and I did the same today.

Do I pull the whole top of the carb off, since these are secondary jets? I was looking at edelbrocks site re WOT tuning, and it says go with 2 stage richer rods 1st.

You know what? I have a new, in the box Holley fuel pump sitting here. I'll replace that in the morning, just to make sure the carb has enough pressure. It may be dropping below the 2 psi minimum reccomended. at 80 gph, I think that'll be good enough. at least to alleviate any uncertainty, don't you think?
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Old 07-30-2003, 06:56 AM   #8
crazy longhorn
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Yes, you need to pull the top to change the secondary jets........the 1407 runs pretty "fat" out of the box tho. My 383 is running the .107 jets in the secondarys. with the bigger fuel pump, you need a regulator, as the edelbrock carbs dont like more than about 5 - 5 1/2 psi on the fuel pressure. crazyL
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Old 07-30-2003, 12:02 PM   #9
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you know, I was wondering why I needed to keep going richer. I thought it was supposed to be pretty rich stock. Maybe it has something to do with my cam?

I bought the Crane Energizer 272. Here's the specs.

I don't wanna get get my plugs any darker at part throttle and cruise, so should i just richen my secondaires? Or if I put a bigger rod on my primaries it won't matter, since it doesn't kick in except under load? I'm using the 8" spring, since it was a whole lot better than the stock 5" spring.
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Old 07-30-2003, 12:51 PM   #10
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do i need any special tools to swap the secondary jets? I've never done it.
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Old 07-30-2003, 02:24 PM   #11
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I suggest you contact Edelbrock Tech. They were a great help to me. Read here:

http://67-72chevytrucks.com/vboard/s...threadid=62157
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Old 07-30-2003, 09:43 PM   #12
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you can swap the secondary jets with a screwdriver, but I really find it hard to beleive that you need fatter jets in the secondaries? The Comp XE in my 383 is .477/.480 lift, & 224/230 dur @ .050, & edelbrock rpm heads...... no flat spots in the powerband. I think i would look at float levels & maybe check fuel pressure. Edelbrock really does have good info on the website on the carbs, & tech support is good . I had to lean the cruise mode a tad on the 1407 on my 383, after I set float levels(one was off enough to foul plugs)....probably dropped in shipping? It still runs pretty rich @ idle, but responce is good. One thing to remember is that if it runs better cold, but doesnt run "crisp " when hot, the jets are too fat. You might even look at ign curve if you have a flat spot that wont dial out. Good luck,crazyL
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Old 07-30-2003, 10:38 PM   #13
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Really? I recurved the distributor a couple of years ago, and it was fine with the old q-jet. I'll check the floats.
As per the fuel pump, I am running a stock pump, but today I finally opened my Holley fuel pump, and there was a note in there saying they substituted the 80gph pump with the 110gph pump, at 7.5 psi. I'll try that too, and maybe need to get a regulator. In any case, instead of the 71/37 rod to go 2 stages richer as per the manual, I ordered the 73/37 rod, to lean out my cruise a little bit, because the plugs were a little too dark for my taste.

I'll pull the top tonight and check the floats. as per the manual, they should have 7/16".

I ordered one stage richer secondary jets, just in case. I still have the stock stuff, and this gives me more room to play.

Thanks guys for all of the help. It means a lot.
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Old 07-31-2003, 11:24 AM   #14
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I had the same problem on my 1406, secondarys did not give me the power I needed. Here's what I did. When you look at the front of the carb, on the right hand side in front of the linkage, there is a rod that goes into the secondary lever. Out the box, this rod is in the middle hole, move it up to make the secondarys open up sooner. No jetting or anything like that unless you have done major engine work.
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Old 07-31-2003, 12:58 PM   #15
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Okay guys, i pulled the top of the carb, and measured the floats. Right on the 7/16" mark, so the UPS guy didn't slam dunk it over the fence. There was just a tad of brown stuff at the bottom of the bowl, and I cleaned it out. OK, I'll try VDOG's advice, nothing to lose, eh? It's probably that simple. Man, these things are easy to take apart!!!
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Old 07-31-2003, 02:12 PM   #16
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Like you I was very unhappy with the Edlebrock, cause I was looking for more performance. Then I saw this fix in Hot Rod Magazine. Unless you had major work, this should work.
Let me know.
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Old 08-01-2003, 01:35 PM   #17
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Before you start doing a lot of hit and miss adjusting, do yourself a favor and contact this guy. mlin@edelbrock.com Tell him what your problem is and the specs on your engine. Im sure he will be of some help.
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Old 08-02-2003, 02:44 PM   #18
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Yeah, i've been sending mesages to him, and we're working on it. Still bogs about 70-75% WOT
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Old 08-02-2003, 03:00 PM   #19
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vdog, are you referrign to the accelerator pump linkage ion the front right?
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Old 08-04-2003, 03:21 PM   #20
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OK, so I replaced the secondary jets with the #1432 as per mr lin at edelbrock. It sounds a little better, but I was wondering why, at WOT, it sprays fuel vapor out of the top of the carb? I would think under WOT, everything would be going DOWN, and not up. Any ideas?

Oh, yeha, at my l;ocal O'Reilly, the counterman said the rods and jets for the primaries werren't in stock, and he was too busy for a special order. Well, I left right then. I went to Autozone, and asked for a special order, but was told the jets were $13.99, and the rods were $18.99. Not for a whole set, but for just a pair! Ouch!. Looks like I'm ordering from Jegs, and paying the shipping.
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Old 08-04-2003, 09:18 PM   #21
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I bought the whole calibration kit just in case.
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Old 08-17-2003, 11:38 AM   #22
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Carb too big for motor. Now the rub, to sell it, or get a 1406 for my SBC and use the 1407 on a BBC? Hmmm... My wife doesn't like my logic: I have a carb that'll work on a BBC, so I must get the rest of the parts. Heheheh. I don't have any BBC parts yet, so I think that's the problem she has.
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