Newbie seeks help with carb swap

[SilverJimmy]

Hey fellas, I need a little help wrapping up my carb swap. I have an Edelbrock 1406 going onto the q-jet manifold. I am using the square to spread bore adapter plate, and have replumbed the fuel line with in-line filter. So far so good...

Now I am stuck on the vaccuum and egr valve connections - I forgot to mark things as I pulled them - damn. Also, I am not sure where the PCV tubing goes from the front of the carb.

Lastly, is that my EGR valve coming from the manifold directly left (passenger side) of the carb? I've read that this needs to be blocked-off, but the block-off plates I see (triangular) dont match the size of the hole, which is square-ish.

Here are some pics of my pickup, albeit blurry, and a few of the engine without the carb/aircleaner. This was supposed to be a "weekend" project lol, and the wife wants the garage back.

Any help or advice on the emissions clean up would be most appreciated.

 

[Swims350]

ok you need to see if the egr hits the carb if so time to fab an egr block off plate. We had an alum. intake from holley had that ame egr port and we made our own plate for it.

The pcv hose goes to the valve in the valve cover and front big port on the carb, the power brakes go directly to the intake or big port on back of the carb that sometimes has a plug in the hole.

if you have a th350 or th400 you need the vac. line to the front of the carb, one side is timed one side is full vac. You need full vac. for it.
The dist. needs the other, which is timed, but alot of ppl use full for it, it's basically whichever way runs and works best for you without ping or spark knock.

Ok your metal tube screws into the back of the carb for power brakes.

I hope you have the correct throttle stud and kickdown stud if you have an auto. if you have a 700r4 you need a geometry correction kit to make sure the tv cable stays adjusted right and don't burn up the trans.

Not sure on the cruise if it needs a special stud or not.

Those hoses in the water neck they can be ditched if you remove all emissions, IF you don't have to pass emissions tests.

I can see by the pics you have an auto, but no kickdown or tv, so I'd say you have a th400 right? They have the electric kickdown switch by the gas pedal, but you still need vac. and it's more then likely hooked to the intake fitting.

 

[crazy4offroad]

Do you have to have egr to pass emissions? If so you may want to be a little more sneaky with the egr instead of just removing it, like a thin piece of sheet metal under it to block it off but make it look like it's still functional and in place. If not, I would take a jigsaw and a piece of mild steel, 1/16" thick or so and make a block off plate you know will fit. If you're running the stock cam you'll need timed vacuum. Other than that I'll have to go outside and take a pic or 2 of mine to show where everything else goes.

 

[Swims350]

I did that with my egr lol used a square body bed arch repair panel to make one. Now I just bought a plate for it, but the thing is alot of them hit on the carb and is why you can't use it. i think they have an adapter though for em.

 

[89Suburban]

 

[SilverJimmy]

Thanks for the replies! No, 86 and older don't require emissions testing here in WA, so I want to clean it up as much as possible under the hood. Thanks for the tips on making the block-off plate, and for verifying that is what it is. I don't have the proper throttle/kickdown studs yet, prolly gonna order from Jegs or Summit tonight (Preferences on favorite online supplier?)

Also, how would I know which trans is in the truck? It's a 3 speed. Like I said... I am a newbie=)

 

[Irishman999]

First off, that looks like a heat riser for the thermal choke on a quadrajet carb.

I just put a Edelbrock 1406 on my 85 and did a write up to clear up any confusion with this swap. Its in the tech section here.

http://www.gmsquarebody.com/forum/showthread.php?t=732

 

[HotRodPC]

Thanks for the replies! No, 86 and older don't require emissions testing here in WA, so I want to clean it up as much as possible under the hood. Thanks for the tips on making the block-off plate, and for verifying that is what it is. I don't have the proper throttle/kickdown studs yet, prolly gonna order from Jegs or Summit tonight (Preferences on favorite online supplier?)

Also, how would I know which trans is in the truck? It's a 3 speed. Like I said... I am a newbie=)

Welcome to GMSB. In a C20, if its the orignal transmission, you should have a Turbo 400. Pretty much a bullet proof transmission that tolerates alot of abuse.

 

[Swims350]

look at the shape of the pan, that tells you what it is.

I would garutee though being 3 speed and no visible kickdown cable it's a th400 unless somebody left the cable off lol.

th350 is square with one corner knocked off at like a 45 degree angle, th400 is weird shaped kinda like texas shaped.