73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Performance => Topic started by: screamin86 on December 03, 2009, 12:20:32 pm
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Alright im having alot of smoking issues with my new motor but its all fuel smoke! My edelbrok 1406 is running very rich. I still need to check my fuel preasure but as far as i know without pulling it apart it has stock jets/rods/springs.the motor is a 350 bored 040 speed pro pistons with stock 601 heads is about 9:4.1 cr 214/224 444/465 112 cam. Long tubes ect. Nothing too wild. I adjusted the carb with a vac gauge but havent cracked it open yet set inital timing at 11 until i can start driving it and tunning more. Plugs are autolite #26 gaped at .035 and a 8mm wire.ive got another 1406 that im pulling off my 82ta soon and may try it. Ive got a jet/rod/spring kit but wondering where i should start and what to set my float levels at. Thanks in advance! :)
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My floats were out of adjustment from the factory. Adjusting them helped with a slight stumble under braking. The procedure for checking/adjusting float level is in the owner's manual (page 9):
http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf
The manual says a MAX fuel pressure of 6 psi (idle). But the scuttlebutt is these carbs prefer 5 psi.
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My floats were out of adjustment from the factory. Adjusting them helped with a slight stumble under braking. The procedure for checking/adjusting float level is in the owner's manual (page 9):
http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf
The manual says a MAX fuel pressure of 6 psi (idle). But the scuttlebutt is these carbs prefer 5 psi.
My floats were also out of adjustment, brand new in the box... I also had to install a fuel psi regulator to cut the psi down to 5-5.5psi for various reasons and it fixed me all up along with a float adjustment. With no regulator I was getting around 7psi to the carb.
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Yeah i was planing on throwing my fuel preasure gauge on it this weeksnd i have a feeling i may need a fpr. Anyone suggest one thats decent but not ovely expensive?
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You can get a "T" and a gauge for under 25 bucks from summit racing.
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I have a Holley 12-803. I think it was $25 at the local parts store. It's also a 2 port setup and does not require a bypass. One side goes to the carb and one side goes to an underhood mounted guage.
(http://i160.photobucket.com/albums/t195/wes2880/78%20C20/Engine%20pics/Regulator1.jpg)
Here's the bracket I made to mount it.
(http://i160.photobucket.com/albums/t195/wes2880/78%20C20/Engine%20pics/Regulator2.jpg)
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Alright im having alot of smoking issues with my new motor but its all fuel smoke! My edelbrok 1406 is running very rich. I still need to check my fuel preasure but as far as i know without pulling it apart it has stock jets/rods/springs.the motor is a 350 bored 040 speed pro pistons with stock 601 heads is about 9:4.1 cr 214/224 444/465 112 cam. Long tubes ect. Nothing too wild. I adjusted the carb with a vac gauge but havent cracked it open yet set inital timing at 11 until i can start driving it and tunning more. Plugs are autolite #26 gaped at .035 and a 8mm wire.ive got another 1406 that im pulling off my 82ta soon and may try it. Ive got a jet/rod/spring kit but wondering where i should start and what to set my float levels at. Thanks in advance! :)
verify rod and jets stock should be 75x47 with a .098 main jet(numbers are based on a .300 system.. probly read .398 or .098 on the jet)
verifiy floats
and you should have a yellow (4"hg) step up spring.
also you can put smaller step up springs in... these mod the rod in and out of the main jets. under high vaccum the rods are sucked down basicly leaning out the carb. they have 5 diferent spring ranging form 3inhg to 7inhg. the high the # the sooner it will lift the rod and richen up sooner then putting a smaller spring. said springs http://www.summitracing.com/parts/EDL-1464/ (http://www.summitracing.com/parts/EDL-1464/)
how far out are your idle screw? 1.5-2 +/- .5 turns is were they should be.
i have ran that cam both with a 600cfm and a 750 cfm carb.. both with a 80gph summit mech fuel pump.. on a 305ci motor neither blew black smoke
also what is all in timing at and what rpm?
what are you useing for a fuel pump?
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It has the factory pump from the old le9 305. I run that cam in the 305 thats currently in my 82 ta and the only time i had fuel issues was when the carb had .098 primarys and .101 secondarys and silver springs.
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take it this is not the same engine???
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By same engine you mean the trucks original engine?
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i think u lost me..
350 with the 214/224 cam and a 1406 smoke like a frieght trian.. original post.
now your talking abuot you LE9 305??? which has the same cam as the 350?? that run stock fuel pump.. had no problem excapt drop to 2psi of fuel pressue are WOT?
what that got to do with the 350?? beside the fact you running the same cam spec in both engines. and 600cfm carbs?
so on the 350sbc what are
tottal timing
fuel pump.
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Here's what I have in my 1406 on a Bone Stock '78 350.
.095 Primary Jets
#7547 Primary Rods
Orange Springs
Secondary Jets are whatever came in it (I didn't write it down)
Mine is setup to runs one step Lean (From Stock) on cruise mode (check your manual for the table)
or follow this link: http://www.edelbrock.com/automotive_new/misc/tech_center/install/1000/1406_manual.pdf (http://www.edelbrock.com/automotive_new/misc/tech_center/install/1000/1406_manual.pdf)
If I recall Correctly the floats should be set to 7/16" <- If the Owners manual seems sketchy on setting floats and stuff, go ahead and buy a quality rebuild kit for it. You'll need one sooner and later and they all have great instructions from my experience.
Excess Fuel PSI can cause flooding, but if it's just a steady smoke stream all the time, somethings wrong. Either some gasket somewhere could be leaking or maybe the needle valves have trash in them and won't seat properly or there may be too much pressure.
I was getting around 7psi from my stock replacement fuel pump from advance. Mine never would run right until I got a fuel PSI regulator. With that being said, I had a 1406 Carb on a 69 Ford 302, a 77 chevy 350, a 73 chevy 400 and never needed a regulator until now. I don't know why, either. Maybe the QC on the carb settings is that bad. I've never seen one unservicable or made of poor quality, but all the ones I've had needed adjustment right out of the box brand new.
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Ok the truck originaly had a le9 305 it broke a ringland off the no.7 piston so i pulled it out! Im however using the fuel pump that the truck had with the 305! Got it? Lol