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OK just rolled under there again and can find no numbers stamped on the housing. I do not think that it has been changed as it still has the lock tabs on the u joint u bolt nuts and no one ever put those things back on. While it is still up in the air I might soak it with cleaner and pressure wash it in case the stamping is faint and I missed it.

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Posted (edited)

Old Guy,

Hope you can see the details in these photos. Took them with my phone sometimes it doesn't do so well. This manual is the one actually put out by Pontiac Motor Division..So I'm 100% sure it is accurate. Got it from my dads immense automotive library 40 some years ago.

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Edited by TWO LANE BLACK TOP

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Did not see anything in that location but will take a closer look tomorrow, right now I am putting my beat up body to bed.

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OK crawled back under and took one of those tooth brush size wire brushes and cleaned the area. The stamping is pretty faint but looks like it could be a 2

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Posted (edited)

#2= 2.69 gear ratio...Not having good day..Season opener at local race track tonight..( We are running in NASCAR Modified Division ) Had car out on track for final tuning..Early This morning was clicking off some really fast laps..Got mixed up with another car.. Went ass end into wall hard..Driver OK.... Car not so good...

Edited by TWO LANE BLACK TOP

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2.69 is about what a 3.5 would be with a 700 R4 in overdrive. Sounds like it might all work out for cruising mileage. It should be ok in town also, the trans is geared low enough in 1st gear that even as sour as the engine was running it had good throttle response at stoplights. Frankly better than I ever expected for a two barrel single exhaust engine.

Sorry to hear about the car but rear is better than front. A whole lot less moving parts back there. Are you going to try an all nighter to get it back on the track for the race or have you just resigned yourself to see the race from the stands?

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Two lane,

IT'S ALIVE! The car is running, I have been driving it for a couple of days and the camshaft seems to be exactly what I was looking for. The low end throttle response is so good that I had to jack up the trans throttle pressure linkage because the trans was shifting way too soon. This should result in improved fuel economy and it appears that it might have but the carb still seems to have problems. What slight amount of driving I did before I took it apart it was sucking fuel faster than I drank beer in my teen years. It is still sucking fuel but not nearly as bad. It has that nasty rich odor when running but not bad enough to be blowing black. I pulled the plugs for a read but I have not had to read a plug since the switch over to unleaded fuel and am not sure what to look for. With about 70 miles on the plugs they look like they just came out of the box. In all my years I have never tweaked any Rochester carb, my carb of choice was AFB for street and end bowl Holley for performance. I know that the end bowl Holleys were notorius for feeding too much fuel when they were in the transition stage coming off of idle before the throttle was open enough to be feeding off of the venturi cluster. Is it possible that the 2GC Rochester suffers the same problem because on the surface streets the throttle is never open enough to reach the venturi cluster. Back in the dark ages we used to plug and meter the transition passage on the Holleys to lean them out while in the transition stage and I would guess that it should be possible on the Rochester if I need to figure that out, or possibly there is another answer. I went through the carb and found no cracks or warpage anywhere everything looked good with a straight edge and the gaskets that came out all had good sealing marks. I plan to take it off and take it apart again this morning to see if I might have missed anything but I don't think so. 

I am not too familiar with anything east of the Rockies but do not think of Indiana as having extreme elevations so I would not think that the original jetting is incompatible with the 1100 ft elevation of Oak Park. 

Have you ever heard of anyone converting one of the late 80's early 90's GM throttle body injectors as they were two barrel and would fit on my two barrel manifold. The two problems that immediately come to mind would be a distributor that would fit in the Pontiac that has the internals to trigger the injector and a crank position sensor. Those post date my years of crawling around under hoods professionally so do not know if they ever used that system on a Pontiac. 

How is the race car. Did you get it on the track for the race or chuck it and go home. Bad omen for opening day, hope the rest of the season improves.

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Posted (edited)

Hello Old Guy,

Hope you can see these photos..and that they actually help you. The special tool that measures the float level is unneccessary..there is a measurement that it is supposed to be..Will have to find out what that is. Will get back to you on that..Sorry I Haven't gotten back to you earlier. Rained out races Sat. night. Race car is going to have to have rear clip put on it. Probably going to be a few weeks before track ready again..We are just doing for fun this year anyway wasn't going to run full schedule anyway..Still sucks though...One major thing between present day gas and what was used in the good old days. When you could buy real gas besides the lead is the ethanol. Gas here in NC uses 10% ethonal..Don't know about Cal Fuel blends..Do know that they're different out there. Anyway ethonal laced gas doesn't get as good mileage because ethanol doesn't have as much energy in it..A gallon of ethanol will not have as much energy as a gallon of gas therefore you can travel farther a gallon of gas than you can with gallon of ethanol..with gas blended with it.  Will hurt gas mileage in the long run..Have a place here where can still buy nonethanol gas. Although more expensive..Can go almost 10 miles farther on a tank of it. Than Can with blended gas on my carburated motorcycle. They  did use throttle body fuel injection on Pontiac but it was the corporate (chevy) engine. In the 1980s..

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Edited by TWO LANE BLACK TOP

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Just signed in with my laptop instead of my phone. Was hoping the photos would be clearer. Don't know what if anything.I can do to remedy that..Any suggestions would be greatly appreciated. Think Mrs. Two Lane might have a way to scan them onto her work computer and then post them directly with out having to take pictures with my phone. Will ask her. As far as throttle body conversion I have never done one so I honestly don't know that much about it. I have always gone the other way from throttle body to 4 bbl carb especially in a performance build. Although I do have a HOT street combination that works really really well with tuned port injection..Hoping these photos will answer some of your carb questions. If you can not see these photos well enough for them to be of any use please let me know will do something different....Mrs. Two Lane just got home she says that she can scan them but will be a couple of days..before she can do it..

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Two Lane,

I did take the carb apart and took another look at it. I had forgotten that the idle circuit on that design carburetor two and four barrel was fed through metered tubes in the main jet wells. Short story is that they are much better metered than the earlier end bowl holleys. It is my understanding that Holey has fixed all of its gremlins in the past few years but I digress. When I pulled the top off of the carburetor the fuel level looked high and with a float in it it would be even higher. I lowered the float about a quarter inch from the level shown in the instructions that came with the carb kit and went out to run a few errands. When I started it up I let it warm up and found that I needed to lean out the idle screws, a good sign, and driving it with the top down you get a lot more of the exhaust smell than you get top up and the nasty rich exhaust smell seemed to be gone. Something as simple as the float level? Anything is possible.

Re: cal gas. We have the winter and summer blend. More ethanol in the summer blend. We are still on winter blend. 

At any rate I will drive it for a while and see what happens. I might drop one jet size and see what happens, It has 64's in it right now.

On another subject I just picked up a 4 row aluminum radiator, with A/C on a 110 degree summer day in our lovely L.A. stop and go traffic I do not think that there is such a thing as radiator overkill. Question is which coolant to run. When I had the Ford diesel I switched it from the green to the red coolant on the advice of a friend that used to be a heavy equipment mechanic with Caltrans. Something to do with the egr cooler. When I did the 100,000 mile service on my wife's Lexus I put it in that and what the h... did the Mercedes SL at the same time. The A/C I put in the car is out of a late 90's Crown Victoria which has an aluminum heater core that did have the predisposition for premature failure in the police cruisers. Ford came up with a variable restrictor in the inlet hose that helped until motor transport found a source of copper heater cores. I checked and the copper cores are no longer available, haven't checked with ford on the variable restrictor yet. So with all the aluminum which coolant is the least corrosive.

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Use the green.. I use it in all my cars..Changed the red out years ago. Have rebuilt several late model engines with aluminum blocks and heads and the ones that had red antifreeze in them almost always have corrosion issues with head gaskets the engine block decks..Cooling passages and the cylinder heads, heater cores etc..Have seen blocks and heads corroded to the point where they couldn't be reused. Especially if is not flushed and replaced every couple years. Basically turns the aluminum into a white powder..the red creates an electrolysis similar to a galvanic reaction like when aluminum is bolted or rivited to galvanized steel without some sort of barrier between them.  Over a period of time it just eats the aluminum...Just curious were you able to make out the photos or do I need to try something different??

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I can sort of make them out but lowering the float level about 1/4 inch lower than the instructions called for seems to have made a tremendous difference. If I need them possibly I can move them to another program that will allow me to manipulate them.

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Two lane,

I am finally back to the Pontiac, life and leaking fuel tank issues. Several posts ago you said that the code 2 diff is a 2.69 ratio. Was that a misprint? finally got this thing on the road and running reliably, Other things had managed to find their way farther up on the to do list than the Pontiac. Plus it took almost 7 weeks to get a new gas tank and sending unit. The only people I found that supply them were out of stock and apparently it takes a long time to have them made. I need to jack up one rear wheel and mark wheel and driveshaft and spin the wheel to get an approximate gear ratio but the way the engine spins on the freeway I would bet the ratio is closer to 3.5 to 3.7.

So I have run a couple of tanks of gas through this thing and it is running good but it still sucks fuel, about 11 or 12 mpg which doesn't make sense because it takes almost zero throttle to keep this thing rolling. My friends 67 Shelby 500 KR does better than that. The carb still has issues. I have had the thing off and apart 4 times and can see nothing. All the gaskets have a good print on them and I can see no cracks or other issues. There are strange things with it like coming home and parking the car on the driveway, which has about a 15 degree up angle, if you restart it within 15 to 20 minutes it is flooded and the float level is already 1/4 to 3/8 lower than spec. With about 400 miles on it I can get a plug read, the plugs on the high runner are brown but the plugs on the low runner are white.

Another thing, the exhaust is so cold on this thing that it is not even burning the paint off of the exhaust ports and the heat riser was not opening, spring too cold. I finally just unhooked the spring and let it fall open and backed the choke spring off a couple of notches. The exhaust still smells fat but the plug read would say different. Maybe it is just the absence of catalytic converters. 

I found a plug and play GM tbi at Howell Engine Development in Michigan which uses the 80-90's vintage gm tbi that I can bolt to my two barrel manifold. Ever heard of them? The other option is to keep looking for a 4 barrel manifold and use the Holley tbi. Or?

The car runs great but I would really like to squeeze a few more mpg out of it.

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Old Guy

Have been really busy the last month or so..I'm sure you know how it is...Out Early. In late...And it's 100 degrees...with 90 % humidity..Haven't been ignoring you..will have time Sunday to get back in the Pontiac frame of mind...

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I understand completely. I have been dealing with a family tragedy this week, no one died but that is the only thing I can think of that would be worse than the present situation. this family stuff will suck the life out of you faster than your 90% humidity. 

Just for giggles I did jack up one rear wheel and spin it while counting driveshaft revolutions and it does appear that 2.69 is actually correct. The tires however are only 25 inches tall which is why the engine sounds like it is spinning faster than it should with that ratio.

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OK, I think that I am getting closer to some answers. I mentioned in an earlier post that the plugs on the high runner are reading richer than the low runner. I was out of town for 11 days and when I got back I went to run a few errands. I tried to start the Pontiac and it would not light. I kept cranking and pumping the pedal and it finally lit. The carburetor was dry. There is a leak  somewhere that I have not found. I have had this problem with more quadrajunks than I can count but never with a 2GC of any kind. Guess I will need to take it apart again put fuel in the float bowl and wait for the leak to appear. A 54 year old carb, I hope that it is just a loose lead plug in one of the passages.

The garage has had a raw gas smell from day one after driving it and parking it in the garage with a warm engine, might have found a reason.

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Posted (edited)

Old Guy

Was just reading your latest post. Was just wondering if you are still running the original fuel pump ?? Also you mentioned one of the lead plugs leaking..Have ran into that problem before myself mostly with Q jets there are two of them in the bottom of the main body of the carb and when they started leaking had the exact same kind of issues that you're describing it Will also kill fuel mileage..and make them smell like they're running way to rich especially on cold start up and extended periods at idle..Also will let the fuel bowl drain dry especially when parked on an incline..Or for an extended period..Would also explain the difference in the intake runners depending on which side of the intake the gas was leaking into.. With the excess fuel puddling in the intake manifold will definitely cause a rich condition which could also explain the cold exhaust manifolds..anyway they used to make a thick gasket part that would go between the main body and the base plate..up into the cavity where the plugs are located If I remember correctly is was called a well seal..They were not included in the standard carb rebuild kit..Had to buy separately but always cured the problem..Would for sure look into that...Also probably wouldn't hurt to look Really really close to make sure that there is not a sometimes impossible to see hairline crack fuel bowl area of the carb..(Getting old and blind sucks)..Sorry that I've taken such along time to respond been having family tragedy also.. On top of long hours at work

Edited by TWO LANE BLACK TOP

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The pump is the one that was on the engine when it came, probably not the original but the original style. I don't know for sure that it is one of the lead plugs that is leaking, I am hoping that it is because that is a repairable problem as opposed to a crack which is not. If it is cracked I have no idea where I would find another one of those carbs or at what price, and finding a four barrel manifold for it is even more remote. I am aware of the thick foam gasket that was available for the Q jet, I used many of them but found that after a little time the gasket would shrink and the problem would return. I found that popping the plugs out turning them upside down and gluing them in was a more permanent repair. It has been so long that I do not remember what glue I used but something like JB weld would certainly work. I would file off the sharp edge of the plug so I could drive them in up side down without gouging the hole. I would glue the plug and hole and tap them in. Once in I would very carefully take a punch and hammer and tap on the plug to expand it, similar to an expandable freeze plug in an engine block. Using that method I never had one of those repairs fail. The only issue is that you must use extreme caution because if you expand them too much you will crack the carb and then you have an ugly paper weight. 

The 2GC is a completely different animal so when I get time, get past the family issues, I will take the carb off and apart again set the float bowl up on something fill it with gas and wait. I wonder if I could put some red food coloring in the gas to make it more readable. If it is one of the lead plugs I have many times used the right size lead shotgun pellets as a replacement plug. drill out the old one, a little glue one pellet and a small pin punch should do the trick.

Just wondering if you have ever heard of Howell Engine Development in Michigan. They have a plug and play 80-90's vintage GM TBI for the engine which is another possibility. The only problem with that is the family problems which in addition to sucking the life out of me are sucking the life out of the bank account and right now there ain't any money to buy one.

Hope that your issues are soon solved.

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Two lane,

It has been a while, the family issue turned into a short career. I found the cure for the 2GC Rochester, turn it into a paperweight. Norm at affordable fuel injection somewhere in Michigan put together a conversion for my Indian based on a '94 chev half ton TBI. It starts great it runs better and smoother it gets better fuel economy whats not to like. 

Also I believe that you stated at one point that you have an extensive automotive library. Do you possibly have information on the 01 to 05 Chev/ GMC truck quadrasteer. I have one that I will need to be digging into and can not find any information on it. I love the maneuverability with the rear steer and will probably be driving this truck until someone offers it again or I can not find or make parts for it anymore. I have been checking on line and purchasing parts as I find them and I believe I have everything I will need.  It is a motor driven dry rack and pinion and can not be that complicated but I would be more comfortable if I had information before digging into it.

None of the on line repair manuals have anything, I have contacted them all. I can not find a factory repair manual for this thing and none of the other manuals cover the quadrasteer. The unit was built by Delphi but they have no connection with the General anymore and have no information so I am at a loss.

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Frosty,

I had already found the Qsteer training, it is a basic overview of how the system works. As for the other stuff WOW!! All the time I have spent looking and you find this overnight, THANKS. I love this truck and with the Qsteer engaged it has a turning radius comparable to my SL500.  I can get around tight parking lots better than most cars, pull a u turn in the street in front of my house without touching either curb and so on. The problem is that if you spin the steering wheel to fast the system drops out of 4 steer into 2 steer  and the rear wheels which are supposed to center in case of system failure go to full lock right. Fortunately this only seems to happen at slow speeds. Backing out of the driveway into the street with the steering wheel near lock in one direction and spinning the wheel too fast in the other direction will set it off every time. Maneuvering too fast in a tight parking lot has also set it off. It appears that the rack is binding and not moving as freely as it should which is causing the system failure. I am hoping that I can fix whatever is wrong with the binding but the other problem is that  the system does not center. There are supposed to be springs in the rack to center the wheels, maybe one of them is broken? Maybe both issues are related, who knows. Maybe there is something in all of those service bulletins that mentions it. I hated homework when I was in school and it still is not one of my favorite things but I guess I need to bite the bullet and start the research. Thanks again I think.

Dwight

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Now here is an eBay link for a complete set of 5 manuals. I know its not cheap, but if you are going to hang onto this truck, its probably a worthwhile investment.

https://www.ebay.com/itm/2002-Chevy-Silverado-Truck-GMC-Sierra-Service-Manual-Set/232520220330?hash=item362348feaa:g:oK0AAOSwDmRZ3nXs&vxp=mtr

I don''t know about you, but the main branch of my local public library houses factory shop manuals for quite a few makes and models and goes back several years. You can't check them out, but you can photocopy the relevant pages, or photograph them with your smart phone.

I know what you mean about doing homework, but it will likely save you money in the end rather than just throwing parts at it. 

 

Edited by Frosty

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Too be honest I don't know anything about quadrasteer..I've heard of it..Not sure if I have even seen one before...Most of the literature I have is from the mid to late 70s back to about 1957 or so...Wish I could be of more help..Still trying to get estate settled....

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