Carburetor question for 66 C-10 with 283

[AslanRules]

Originally Posted by markeb01

Don't be bummed, that's not bad news, just different information. If you still choose to put on a new Edelbrock manifold and carb, the intake ports will actually line up better. You can skip the oil fill tube and just install any late model valve covers with breather holes. The only downside would be if you had really wanted it to be an original numbers matching truck.

Hopefully someone else has the answer on the 350/305 question.

Thanks, Mark. Y'know, I'm not sure exactly what I was expecting, since this is my first foray into the world of restoring old cars/trucks. I had assumed that the truck had the original engine in it. Silly me. After reading lots-n-lots of blogs and forums, I am realizing that an original numbers truck is the exception rather than the rule, and that I would have really gotten a steal if I had accidentally bought one.

So....since this is either an 1985 305 or a 1972 350, I know I can skip the oil fill tube and go with the twist-in oil-fill-cap, and get newer covers with breathers. BUT.....I would like the engine to look older and more vintage, so I will probably still go with the oil fill tube and keep my older valve covers. Is there any reason NOT to do that? If the engine can still breathe as well with the current configuration, and if there's not too much oil back-flow out of the breather cap, I'm happy to leave as-is.

Boy......this has been, and continues to be, a real education. I love it !!!!

Randy

[AslanRules]

Originally Posted by raycow

There should be a casting number and date on the top rear of the block behind the intake manifold. Since you have already decoded the stamping in front, the casting date will give you the year for positive identification.

Ray

Ray,

Thanks for the message. Yeah.....I was hoping to avoid crawling in and around the engine compartment to find the casting number on the bellhousing/transmission mounting flange. I'm not even sure I could find it with the engine still in the truck.

Are there any other tell-tale signs between a 1972 and a 1985 small-block that would suggest what YEAR it is? If we can pin down the most probable YEAR, then that would let me know if it's a 305 or 350......at least until I can crawl under the hood with de-greaser in hand....or until I take the engine out or remove the heads at a later date. I don't suppose it matters much for my present purposes of replacing the valve cover gasket and carb.....I'm just curious.

So......everyone put your collective grease-monkey heads together and see if you can make an informed guess.

Thanks,

Randy

[markeb01]

Hi Randy, you can still run a manifold with the oil fill tube and breather in front, but there still must be some place to connect the pcv valve. It either has to be connected to a valve cover, the back of the block (like on a 283 which won’t work on your engine), or in the back of the manifold as described by raycow.

There are a few options connecting to the valve cover – use any later cover with a preformed hole as described earlier, fabricate something like what I’ve done (which requires machine shop abilities), or buy one of the new Corvette style covers that have a flat boss on the side above one of the valve cover hold down screws. This keeps the top of the valve cover smooth. They are available in a variety of styles but are spendy:

http://www.yourcovers.com/valve_cove.../sbc_holes.pdf
http://www.yourcovers.com/valve_covers_11026.php

I have seen some guys install early sealed covers with the smog valve connected to the oil fill tube using a factory fill pipe designed for the purpose:



Unless the road draft tube is in place (which a 305/350 does not have), this arrangement doesn’t really evacuate the crankcase. The only source of fresh air is the breather cap, which will offer less resistance to the smog valve than the crankcase. The breather will flow lots of air, but the crankcase will have no source of incoming air.

The other option being an attachment at the back of the intake manifold. I’m sure this would work fine, but an effective baffle doesn’t seem like an easy task. The original baffle in a 283 block is a vented metal can about the size of a frozen orange juice container that lies in the lifter valley, connected through a large hole in the rear of the block wall. Here’s an example:

http://www.classicchevy.com/product....&dept%5Fid=388

Enough study might produce an easily workable design, but I don’t have one readily available to offer. Anything that could potentially come loose would end up dropping into the lifters/pushrods.

Here’s another thread on the topic of pcv connections for some light reading:

http://www.jalopyjournal.com/forum/s...d.php?t=151629

Regarding identification without the casting number, here’s an interesting thread full of opinions that all boil down to the fact - you need the casting number:

http://www.thirdgen.org/techboard/fa...305-350-a.html

[Slow Build]

If I could kidnap this thread for a quick question. I have a 283 with the oil fill breather and road draft tube. I'm switching manifolds from Edelbrock SP2P w/ oil fill tube to an Edelbrock 2101 w/o oil fill. I currently have valve covers with grommets for breathers on both sides. I'm planning on running a breather on one side and a breather with PCV tube on the other. I'm guessing that means that you need to put a PCV valve inline to the air cleaner. I'm also running an Edelbrock #1405 600cfm carb if that makes any difference (I'm currently trying to find someone to trade down to the #1403 or #1404 500cfm carb).

I this case what should I do with the draft tube (block it off, use as breather, ect...) ?

[raycow]

Reading through that rather lengthy thread on Third Gen, I came up with one possibly useful piece of information: "all pre 80 smallblocks had driver side dipsticks, displacement doesn't matter".

This was in post #44, if anyone wants to look.

Ray

[markeb01]

Originally Posted by Slow Build

If I could kidnap this thread for a quick question. I have a 283 with the oil fill breather and road draft tube. I'm switching manifolds from Edelbrock SP2P w/ oil fill tube to an Edelbrock 2101 w/o oil fill. I currently have valve covers with grommets for breathers on both sides. I'm planning on running a breather on one side and a breather with PCV tube on the other. I'm guessing that means that you need to put a PCV valve inline to the air cleaner. I'm also running an Edelbrock #1405 600cfm carb if that makes any difference (I'm currently trying to find someone to trade down to the #1403 or #1404 500cfm carb).

I this case what should I do with the draft tube (block it off, use as breather, ect...) ?

If you're going to use a breather on one valve cover and connect the pcv valve on the other, the road draft tube hole is really unnecessary. The simplest and most permanent solution would be to fill it with a soft plug/freeze plug. I normally use red Loctite on freeze plugs, but seal it with whatever you are most comfortable with.

The pcv valve should be the type that plugs into the valve cover grommet and connects to full manifold vacuum either at the front center port of the carb base, or my preference is the threaded port at the back of carb. If you’re running power brakes, the vacuum booster hose can connect to the manifold port behind the carb so there is no interference between the two.

Here’s what mine looks like, although the valve is routed differently:



PCV valves are available in straight or 90 degree designs. The 90 degree style minimizes the amount of hose needed and makes for a cleaner appearance. If you already have a breather with a hose barb and want to use that instead of a valve that plugs directly into the valve cover grommet, an inline valve will work equally well.

The pcv/smog valve should never be connected to the air cleaner, it must go to full manifold vacuum. In fully sealed systems, the cap on the opposite valve cover would have a hose barb that could be connected to the air filter. Unless a legal necessity, most street rods run a breather on the opposite side instead. Venting the engine into the air cleaner prevents crankcase fumes from escaping into the atmosphere, which is great for the environment. It also allows fumes in enter the carburetor and air filter. Depending on how old the engine and amount of blowby, it can make a mess of of your carburetor and alter mixture settings over time.

[AslanRules]

Originally Posted by raycow

Reading through that rather lengthy thread on Third Gen, I came up with one possibly useful piece of information: "all pre 80 smallblocks had driver side dipsticks, displacement doesn't matter".

This was in post #44, if anyone wants to look.

Ray

And in post #11. Aaarrrrrggggggghhhhhhh !!!!!!

Looks like it's a 1985 305.......I was hoping for a 350.

But I will crawl around and try to find the casting # to make sure.

Thanks Ray.

So..................any general comments about the 305 vs 350 vs 283?

Randy

[geezer#99]

Easy to find the casting number on the drivers side rear of the block. Use a big mirror to locate it. I use the wife's big mirror. SHHHH!!! Don't tell her. LOL!!!

[Slow Build]

Originally Posted by geezer#99

Easy to find the casting number on the drivers side rear of the block. Use a big mirror to locate it.

Easier with a digital camera. Just point it in the vicinity of the drivers side back of the engine down toward the bellhousing.

[Rich 5150 69]

[QUOTE]I'm heart-broken. I finally found the numbers off the front pad, as suggested. This is NOT the original 283 engine that came in this truck. The ID # is V0111CDH. According to my research, the engine was made at the Flint Engine Plant on January 11th. The CDH suffix indicates that the engine was made for a CAR, not a truck, and is either a 1972 350, or a 1985 305. The VIN on the pad does NOT match the VIN on the tag in the driver's door.
/QUOTE]
Randy The good news is
CDH acording to the hollander manual is 1972, corvette, 200 hp, 350. But it has the 305 heads on it, which is alright, higher compression just smaller valves which will help with increased lower throttle response. Its either a 014 or 010 numbered block

[AslanRules]

Originally Posted by markeb01

Hi Randy, you can still run a manifold with the oil fill tube and breather in front, but there still must be some place to connect the pcv valve. It either has to be connected to a valve cover, the back of the block (like on a 283 which won’t work on your engine), or in the back of the manifold as described by raycow.

http://www.yourcovers.com/valve_cove.../sbc_holes.pdf
http://www.yourcovers.com/valve_covers_11026.php


Regarding identification without the casting number, here’s an interesting thread full of opinions that all boil down to the fact - you need the casting number:

http://www.thirdgen.org/techboard/fa...305-350-a.html

Thanks for the link to the thirdgen article. It's not exactly what I wanted to hear re: dipstick location, but I think the mystery is almost solved: it's most likely a 1985 305. I still have to climb through some grease in the next few days and find the casting number.

Wow......those "yourcovers.com" valve covers are awesome. But I agree, probably a little pricey for what I'm trying to do. I've pretty well resigned myself to having at least 1 valve cover hole for a PCV valve....with air intake through the filler cap.

Question: So...you have a significant concern about the existing PCV valve location, since there is no baffle and sharp edges where the cover was cut, right? I'd rather replace the covers than have the bottom part of the grommet fall down into the lifters.

I have been shopping online for valve covers. Which covers do you like best?

#1: http://www.billetspecialties.com/ite...id=235&pid=475

#2: http://cgi.ebay.com/ebaymotors/ws/eB...#ht_2063wt_939

#3: http://cgi.ebay.com/ebaymotors/ws/eB...ht_1876wt_1165

#4: http://cgi.ebay.com/ebaymotors/ws/eB...#ht_3316wt_897

#5: http://www.summitracing.com/parts/CAL-196186/?rtype=10

Any and all opinions welcome.

Randy

[AslanRules]

Originally Posted by Rich 5150 69

Randy The good news is
CDH acording to the hollander manual is 1972, corvette, 200 hp, 350. But it has the 305 heads on it, which is alright, higher compression just smaller valves which will help with increased lower throttle response. Its either a 014 or 010 numbered block

Rich,

But this chart indicates that CDH was used twice: the 1st time in 1972, as you mentioned, but also a 2nd time in 1985: 305 cid @ 150 hp.

And......since my dipstick is on the passenger's side, that dates the engine to post-1980.

The blue-painted engine is chipping in areas and shows orange paint underneath......this is encouraging as a sign of an earlier engine, but who knows if the orange paint is original.

I'll try to look at the casting number tomorrow.

BTW......how can you tell that those are 305 heads?

Thanks,

Randy

[markeb01]

Originally Posted by AslanRules

Question: So...you have a significant concern about the existing PCV valve location, since there is no baffle and sharp edges where the cover was cut, right? I'd rather replace the covers than have the bottom part of the grommet fall down into the lifters.

I have been shopping online for valve covers. Which covers do you like best?

#1: http://www.billetspecialties.com/ite...id=235&pid=475

#2: http://cgi.ebay.com/ebaymotors/ws/eB...#ht_2063wt_939

#3: http://cgi.ebay.com/ebaymotors/ws/eB...ht_1876wt_1165

#4: http://cgi.ebay.com/ebaymotors/ws/eB...#ht_3316wt_897

#5: http://www.summitracing.com/parts/CAL-196186/?rtype=10

Any and all opinions welcome.

Randy

Hi Randy, I have no concern with the "location" of your existing pcv valve, and even the lack of a baffle isn't that much of a problem because the valve itself is nearly vertical above the rockers (compared to behind the engine where inertia will push oil to the rear). My concern is the grommet itself resting against the sharp edge of a piece of sheet metal. It's not like a grommet holding a wire in the firewall, there is going to be a lot of vibration living on the engine, and with a hose flopping around above the valve for leverage, the continuous movement may eventually slice the grommet around the perimeter allowing the lower half to fall away - into the engine. Valve covers designed with the hole in the same place have either a rolled edge or a formed flange to protect the grommet. Some have a built in baffle while others do not. I've used both and never saw any noticeable difference.

As for the valve covers my preference would be #3. They remind me of a set of Cal Custom covers I had on my 283 powered 54 Chevy sedan back in the 70's. You'll notice I had the closed breather connected to the velocity stack, and yes - it made an oily mess out of my carburetor. It was a learning experience.



I don't care for the first two with the script offset so far, just doesn't look right. The Edelbrocks look too 80's / Camaro for me, although they are certainly popular. The Summit covers look just like #3 for a lot more money. If I hadn't wanted mine to look like an early engine, my preference was the square Mickey Thompson covers, like these currently on eBay. It really comes down to personal preference.

http://cgi.ebay.com/ebaymotors/Micke...Q5fAccessories

[likaroc13]

i like #3 valve covers as well...i plan to switch to that aluminum finned style in the near future...i saw the Cal Custom ones at Summit Racing...i wonder if those are any different...if you get them, i'd be interested in knowing how they turn out

[AslanRules]

Originally Posted by markeb01

Hi Randy, I have no concern with the "location" of your existing pcv valve, and even the lack of a baffle isn't that much of a problem because the valve itself is nearly vertical above the rockers (compared to behind the engine where inertia will push oil to the rear). My concern is the grommet itself resting against the sharp edge of a piece of sheet metal. It's not like a grommet holding a wire in the firewall, there is going to be a lot of vibration living on the engine, and with a hose flopping around above the valve for leverage, the continuous movement may eventually slice the grommet around the perimeter allowing the lower half to fall away - into the engine. Valve covers designed with the hole in the same place have either a rolled edge or a formed flange to protect the grommet. Some have a built in baffle while others do not. I've used both and never saw any noticeable difference.

Mark,

By "current configuration", I was referring to the PO's method of non-stock defacing of my vintage valve cover....not where he defaced it. But you do make a good case for replacing the cover in order to avoid rubber foreign bodies falling into the lifters. I wish there was a way to keep the sheet metal from cutting the grommet, but I guess there isn't. So, looks like I'll be getting the finned covers (#3).

I made some photos of my casting number today and I am posting them below.

The 1st photo shows the numbers as my camera viewed them, standing on the front bumper and leaning way over the engine. The distributor is seen on the left, and the back of the driver's side valve cover is seen on the right of the photo. The casting number is on the left, and another number is on the right. I am assuming that it's the Date Code, but it doesn't look the way it does in my research. In fact I think that the casting number should be on the right next to the GM insignia. Anyway...........



Here's a similar photo, but I have flipped the photo 180 degrees so that the numbers are easier to read:



Here's another view of the casting number:



Here are 2 views of the presumed Date code:





According to the casting number, this is definitely a 305, 1980-84. The Date Code is a little harder to decipher. The format should be "Alpha-#-#-#", but this one appears to be "#-#-Alpha-#".

Anyone have a clue here?

BTW....is that the oil pressure sensor next to the distributor?

Thanks,

Randy

[Rich 5150 69]

Yes it is a 305 and yes on the oil pressure...!

[AslanRules]

Originally Posted by Rich 5150 69

Yes it is a 305 and yes on the oil pressure...!

What do you think about the alleged Date Code? Wierd, eh?

[raycow]

It looks like "5.0 L" to me - 5.0 liters, or a 305.

[AslanRules]

Originally Posted by raycow

It looks like "5.0 L" to me - 5.0 liters, or a 305.

I think you are correct !!! I didn't know that they put that on the block.

What do you think the last digit means?

[AslanRules]

Originally Posted by AslanRules

I think you are correct !!! I didn't know that they put that on the block.

What do you think the last digit means?

Perhaps a "G", meaning Gasoline (vs. Diesel) ???

Maybe an "8", for the # of cylinders???

[Rich 5150 69]

G - Gas Possibility...!

[Slow Build]

Hey Mark
Since I'm in here should I bother removing the inside baffle for the road tube or is it a no harm no fowl thing. The only real problem I see that it could cause is if the bolt ever backed out on it's own.

[raycow]

I would leave it in as long as it clears whichever intake manifold you are planning to use.

Ray

[markeb01]

If it were mine I'd leave it in place. Not sure if removing it may cause excessive oil to flow through the opening, or if plugging the hole might cause other problems. I don't think the screw backing off will be much of an issue, they lived there for decades and I've never heard of a problem. For extra insurance a dab of Loctite and a new lock washer wouldn't hurt anything.

Edit - I can't see clearly enough to determine what style bolt that is, but replacing it with a new one that has the serrated flange washer built in would also be cheap insurance.

Also, should you ever decide to go back to the old configuration, it would be easier if you didn't need to search for a replacement baffle.

[Slow Build]

Thanks for the advice.

The Edelbrock performer manifold is on now. I went to get a new carb base gasket but that seems to be a problem. Unfortunately I didn't take the two old gaskets with me. I thought it would be pretty easy. NOT. The people at both Kragen stores were absolutely clueless. They sell Edelbrock carbs and manifolds but they know what to do if you ask for a gasket to go between the two. the guy was looking through catalogs for about 15 minutes while I was getting other stuff but still didn't know what to do at the first Kragen store. The second store at least said he could order one. So first thing tomorrow I have to go to another auto parts store with people that have a clue. I did see in one catalog that it is a two gasket set. That seems strange too but thats what I took off. Can anybody tell me if the two piece gasket set is nessesary or is there another simple option. I wish I could ask the people that get paid to do it but that's just asking too much.