Lousy aluminum casting quality

[Michael W.]

Re: Lousy aluminum casting quality

Who said that it's a sPace Car?

[Barry K.]

Re: Lousy aluminum casting quality

Patrick

no, this isn't a Pace car, just a regular '78 L82.
I never assumed it was a rare car, even with the low milage, just a somewhat more desireable example (relatively) of a '78 because of the low milage and full documentation but I'm not unrealistic about it - it's a '78 so it's not like it's ever going to be worth a lot of money no matter what.
I just happened to stumble across it and was able to get it pretty cheaply so decided to pick it up.

Two reasons that required me to remove the intake - one, the intake, and the entire motor and engine bay needs a THOROUGH detailing because of it's previous neglect and it was so bad looking under the hood I figured taking everything apart to clean, repaint, etc was the easiest way of doing the job correctly so it looks good like it should. Two, the car did not run. When I had it flatbedded to my house and in my garage I was able to start it after a while with some major coaxing but she ran like crap, wouldn't idle at all on it's own, and just putting the tranny in gear was enough to make her stall, etc. My idea, based on a completley non-mechanical background and VERY LITTLE experience working on cars (only started working on my '65 last Aug), was that I'd take it apart, clean everything including have the carb rebuilt, put it all back together again while checking everything once it was clean such as the vacuum hoses for cracks, etc, and she if she ran any better once everything was cleaned and reassembled. If she ran good, than great, if not, than I'd start diagnosing the problem but than I'd be able to (hopefully) rule out certain areas as potential problem areas since I'd already inspected them as I reassembled the car.

[Barry K.]

Re: Lousy aluminum casting quality

John
I was wondering about the pipe fitting plug on the side also

[Gary #41345]

Re: Lousy aluminum casting quality

We are talking a sand casting here!!!! You are going to get voids and plenty of them... they were not looking for a 4-8 micro finish on the outside of a sand casting. The voids actually lighten the overall weight of the product and in engine parts that can be a disireable thing. The machined surface or any other sealing surface is another matter, a surface finish requirement of 16 micro or better is often on the blueprint.

[Barry K.]

Re: Lousy aluminum casting quality

Gary
you may be very correct. I don't pretend to know anything about various types of castings. All I know is that an intake, even one in a late model C3 that is largely covered by a big air cleaner assembly, and by lots of hoses and vacuum lines is still a very visible part of the motor and one of the first things someone notices on a motor - at least I do. For such a part of the motor to have so bad of a cosmetic appearance to it because of the flaws of the casting I just find hard to believe that any car company would find acceptable.
I haven't studied many late model C3's to know if this is just common or mine is unusually poor quality, but I just find it hard to believe that something like this would be put onto a car and sold to a customer.
Than again........ maybe I shouldn't be overly surprised. I've seen other cars of this vintage with original paint jobs that I would expect better results if I took thje car to Maaco! I know someone with an original '78 Pace car with only 53 miles on it. The car is never used or taken from the garage except once every two years it's loaded on a trailer, taken to DMV to be reregistered, than unloaded back at home again. The car still has the plastic on the seats and carpet. The paint job on the car is just awful and shows many runs, sags, and a TON of orange peel but it's the original paint job and in the exact condition it was when it left the factory floor.
so, I suppose if they will let a car out with a paint job like that they sure aren't going to care about what an engine part looks like.
Still, I look at it as Chevy was just willing to accept a very low level of quality control and a very low level of standards for what they felt was acceptable as a finished product.

[Gary #41345]

Re: Lousy aluminum casting quality

One of the many problems with out sourcing production parts to cheaper suppliers, the real problem is that it is "THE" norm today and in many manufacturing circles considered "THE BEST PRACTICE" in place of using your own employees. Who pays in the long run the consumer of course but GM did take a hit in the wallet and realized they had to pay a little more attention to quality vs profit.

[Patrick H.]

Re: Lousy aluminum casting quality

Nobody.

But, if that many 1978s (which happen to be that way due to Pace Car status) are very low mileage, another low mileage 78 is not an uncommon car. I was using the number of Pace Cars to describe the large number of low mileage 1978s relative to virtually any other year.

Patrick

[Paul L.]

Pipe Plug on Left Side?

Barry,
You have a pipe plug on the left (driver's) side?

[Barry K.]

Re: Pipe Plug on Left Side?

Paul
yes, there is a fitting in there that is almost flush to where it's mounted in the intake. you have it in yours also, i can see it on the opposite side of the picture you posted.
do you know what it's for?

[Paul L.]

Re: Pipe Plug on Left Side?

I think that's the plug on the vertical surface just below the carb mounting area, driver's side. If I remember correctly (that intake is stored now) it has a large Allen wrench head fitting. Having said that I have no idea why it is there....It is just plugging a hole.

[Kevin M.]

The Picture

Here.

Kevin

[Gary S.]

Re: Lousy aluminum casting quality

I agree. While I don't have extensive personal experience with aluminum Corvette intakes, it doesn't take a rocket scientist to see the roughness of yours.

The aluminum intake on my 66 L79 was actually quite nice (almost said pretty ).

Gary

[Joe L.]

Re: Lousy aluminum casting quality

John------

The 3/4" NPT driver side fitting was added to most, if not all, small block manifolds about 1973. This included cast iron as well as aluminum varieties. I don't know the purpose of it. However, it's also notable that all of the manifolds that have it are also EGR-type manifolds. I believe that there is some connection between the EGR and this fitting. It may be some sort of "access port" required for manufacturing reasons. I don't know of any application that actually uses this port for some other fitting.

[Paul L.]

Re: Lousy aluminum casting quality

Thanks Joe,
It puts my mind to rest that someone with your knowledge does not know the answer as well. I thought I was pretty versed on late C3s but that question stumped me.

[Mark #28455]

EGR crossover

Isn't that plug in the hole that allowed the EGR to crossover to both sides of the intake?

Mark