Thread: 305 Questions!

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Ok I have a list of questions I need to know about this 305 I have of mine. I will not ask them all at once so not to get everyone confused but I will start out with a couple here. First off this is a 1985 Chevy Custom Delux 10 truck. It has the original 305 with AC and carburated. Here are my questions.
1.) On the exhaust manifolds there are these metal hoses comming out of them. One on each side. The go to this little round box looking thing and a wire or two from that box to a thing on a belt pulley below the Alternator. It looks like an alternator but isn't of course and that is all that is up to that thing. What is this thing?
2.) Can I take it off and not have those hoses and run some nice headers?
3.) Ok I need plugs and wires very bad. I see there are wires for over the valve covers and then some for UNDER the headers. Which look better and cleaner and will either one work?
4.) What are some good plugs?

I plan to get that HEI upgrade kit from Pertronix with the 50,000 volt Ignition coil and all so will need thick wires like 8mm I guess.

Thanks for any help here! I am in need of plugs and wires bad so thought I would change headers and everything as well. I took or tried taking a plug out and they were like froze in there, I took this heavy duty lube and sprayed it all over and plug snapped off at the block. Luckily only the top part did and I was able to barely get a wrench and take it out still. I haven't messed with the others yet. The truck is running real rich and the plugs were changed before the guy said but foul he said as well. They were really black and caked with oil. I don't know if it's burning oil as well or what but I will do the plugs and wires, drive it and see if it's burning any oil and go from there.
Ok well thanks again!

Shawn-

The metal hoses are air hoses. The idea was to inject oxyogen into the exhaust system before you got to the cats. Good for emissions, but not really nessicary. Even my moms 4100 will pass without them. As for the "alternator looking thing" thats the pump to those hoses. You'll find it also has larger hoses that go elsewhere. If you plan to convert over to a carb, their really not nessicary. If you have TBI or the infamous GM "Feedback" carb, you will want to keep this. Otherwise, It'll constantly force the engine to run lean. As for the wire question, I would reccomend over the valve covers. That way its not such a pain to change them. As for good plugs, my standard reccomendation is bosch platnium. I have yet to see another plug that you can walk into advanced auto and get a new one No Questions Asked.

Ok. Likely those hoses go to a smog pump, you should be able to remove it and get headders. Both kinds of wires work, over the covers need looms but don't have heat issues like the under headders do. If you want clean looking and you are able to use a standard HEI cap, get a crossfire cap, there a internally wired distributor cap that allows the wires to each side of the engine to that side of the cap, so wires don't cross over. The only supplier of the crossfire cap I know of, is www.yearwood.com and it is pricey, at 49.99 but worth it if you want a clean look.

Ok awsome. So if I take the exhaust manifolds off then I can take that belt driven smog pump off right? Plus that should be nice, one less thing out of the way. Also Denny, I plan to get an edelbrock Performer carb instead. This stock one is gummed up like crazy. The truck never starts up right away, takes it a while. The guy said he pumps it twice, tries cranking and then two more time. I just hold it to the floor and right when it gets to the floor I crank it. That way works easier for me at least when I tried it. Only thing is that I still have to get inspection but today some kid said on his Honda car (ricer) he gets the exhaust check where they put the probe in the tail pipe and check for the exhaust gas. His car is like a 02 or something so I am hoping they don't do that to mine. I want to get a Edelbrock carb, intake manifold and a cam kit. I will hold on the cam kit for now but just wanted to add that. Also I will get some glasspacks with some headers. I am thinking, if I can't find someone to just pass this thing for me (which my dad said he may know someone) then I am going to keep the old cats and pipe, etc and just cut the pipe to where I can put the whole assembly on and off easily and switch it out when inspection time comes around.
Ok so here are my two other questions. (doing it this way to make it easier to follow along since when I type I kind of go all over the place and get mixed up).
1.) Can I take that pump off and the belt?
2.) Is it ok to take that wire crap off and run a Edelbrock carb and intake manifold to free up some power?
3.) Cerma-Coat Headers from Dynomax any good? They have Jet Hot coating inside and out and are 16 gauge tubing and stand up to 1300 degree's F. $240 from Jegs, part # 289-86003

Seems like Hooker headers are about 300- 400 bucks for the coated ones or even plain besides the Comp headers which are about 160.
Thanks a lot guys! Dave, sorry for bailing out on you like that today after I asked you that question. I didn't want to sound rude but I looked at the clock and saw that I was already supposed to be headed to the college already.

Wow, you gave us a lot to comment upon. In the future, post fewer querries and you'll get better answers.

anyway.. if you are subject to the smog tests, you would do VERY WELL to show up there in person one day, and get some information on just what they check, and how hard-nosed they are. By-the-book, they are FIRST supposed to do a visual check. That means the smog pump had better be there, and any obvious after-market components had better be CARB approved. Inquire before you order and make sure. CARB approved parts will come with stickers, which you will want to display prominently under the hood for the convenience of the inspectors.

This does not necessarily mean you can't get headders... you just have to make sure they are CARB approved, and that they have the inlets for the smog pump. Here is another caveat: the smog pump is an industry cheat. They claim that by adding clean air into the exhaust, it allows the unburned gasses to burn off. THAT'S CRAP. All it is doing is DILUTING the exhuast mixture, thus fooling the 'sniffer' they stick up the pipe. ( rather similar to the small perforations around the circumfrence of a cigarette filter, but that is another rant ). Before you go replacing the carb, considering you are under inspection obligation, you would do well to just get your original carburetor rebuilt. While you are at it, double-check your vacuum lines, make sure everything is as it should be. You are going to need catalytic converters, but there are high-flow 'cats' available. Your old cats are shot, they only have a functional life of 3-7 years.

Call Summit ( 1-800-230-3030 ) and ask for a free catalog. Better wear a baby bib the first time you read through it, cause you will be drooling all over yourself like a dog waiting for scraps at Thanksgiving.

Depending on how much wrenching you like, you could always consider getting the vehicle in good running order for the inspection, then pulling all the junk and throwing it in the corner till next year when you'll have to put it on again for inspection.

You can save a bundle on the headders, by just ordering SUMMIT brand, then wrapping them with THERMOTEC heat wrap. You'll need one roll-per-headder. You can leave the wrap 'naked' and it will develop a patina like a brown paper bag. otherwise you can use hi-temp paint of your color prefrence. Hold the nozzle about an inch from the wrap, and absolutely soak it. It'll take a can per headder. the aluminum REALLY looks nice! Use some of the 'extra' wrap to make booties for your spark plugs. Just unravel some of the wrap to make yourself some 'thread', then use the thread to sew the wrap into sleeves. Slide the sleeves onto the plug wires, and VOLIA! you got booties for your plug wires, and a WHOLE LOT CHEAPER than what Summit wants for them.

EG

Thanks for the info Firebird. I am about to call the local speed shop and ask them about the laws here. I am going to get some good Taylor wires or such, the Pertronix HEI tune up kit with the 50,000 volt ign coil, and air filter. I will check on that stuff you said about and go from there. I will try finding a guy first that wont care about the visual and ask the speed shop owner if he knows of anyone like that around here.
Thanks again and anymore info is still appreciated!

I had a 305 with the Quadrajet 4barrel carb, like I think your talking about. I had the smog pump out the day I got it. In my state, there is no emmissions testing, and as long as you know where to go for state inspection, your ok. Those q-jet carbs are junk. I also had the airpumps and manifolds with blowdowns on my ford 460. I ripped those off that too, with no change in the performance. I can't comment on the spark plug wires, but I can say, you will have alot less junk under the hood once you switch to the edelbrok carb and headers. Once you do that, you could eliminate alot of hoses and wires and junk that takes up space and looks bad. Good luck.

460_fan, thanks man. Yeah well I called the shop today. The guy said take my cats and everything off and go with a NON EGR manifold and carb from Edelbrock and a Holley carb (which I think I will go Edelbrock again, they make nice street carbs and a bit cheaper) and he will show me some guys that will just pass the smog test and all for me. Which will actually be nice. I will keep all the old parts under the house in a box just in case for years from now if I ever go to sell it. I ordered the MSD HEI upgrade kit. Was 20 bucks more than the Pertronix but the guy at the shop said the MSD is a much better unit. Taylor 8mm wires, and then he said go with autolite plugs. He said the platnums are ok but the Autolites are better. They all drag race and everything else and know what they are talking about and I have known the guy for quite some time now so I trust him on his word. I also ordered the plain Edelbrock series air filter, just the plain 25 dollar round one. I am going to get the headers and manifold, etc next though once I find out for sure if I should run EGR or not.

I have some pictures I took of before and I will have after pictures on Monday most likely. I will wait till then and post all my stuff. I painted my door panels black since they were old and you can scratch them and the plastic would fall apart you know. So I sanded them down, primered them with the plastic primer stuff and then plastic paint. Won't hold real great but good enough for now. Updates all on this next week though. Sorry for two posts in a row.