1970 LT-1 Ignition Shielding

[James H.]

Can anyone recommend a good resource, book, manual, website, etc. that can give me the necessary details on how I properly install the complete set of ignition shielding on my 1970 LT-1?

Thanks

Jim

[John S.]

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[James H.]

Re: 1970 LT-1 Ignition Shielding

Thanks John. I do have a AIM, so I will check it out.

[Ron G.]

[James H.]

Re: 1970 LT-1 Ignition Shielding

Good advice.

I will check it out.

Thanks

Jim

[James H.]

Re: 1970 LT-1 Ignition Shielding

I am installing the lower ignition shielding, while the engine is on the engine stand. I have had the car for a while, but it never did have the shielding on it before, so all of this is new to me. I was thinking of putting the spark plugs in, connecting the wires routed through the lower shielding, and bundling them up on top of the manifold, out of the way for engine installation. Does this sound like it will work? It seems like a real pain to put the shielding and wires after I put the engine in the car?

Also, can anyone give me some details on where the "oil pan wire clips go"?

Thanks

Jim

[John S.]

[James H.]

Re: 1970 LT-1 Ignition Shielding

So far so good... I think... So the wires first enter into the top of the "boomerang" shield, and then down behind the shield, curving to the front of the engine inside the shield. Behind the shield, at the point where the two wires drop past the top of the oil pan, where the pan it attaches to the block, use a clip there at the nearest pan bolt an put two wires in that clip and then the two wires continue down inside the boomerang shield to the front two plugs on each side? Do I have that correct?

Would these clips be painted Orange?

Thanks!

Jim

[Terry M.]

Re: 1970 LT-1 Ignition Shielding

So far so good... I think... So the wires first enter into the top of the "boomerang" shield, and then down behind the shield, curving to the front of the engine inside the shield. Behind the shield, at the point where the two wires drop past the top of the oil pan, where the pan it attaches to the block, use a clip there at the nearest pan bolt an put two wires in that clip and then the two wires continue down inside the boomerang shield to the front two plugs on each side? Do I have that correct?

Would these clips be painted Orange?

Thanks!

Jim

Yes Jim you have it right, I think. Terminology may need some translation, but if I am translating right (up and down are a little confused with front to back) you have it. It is not rocket science. The path will be obvious once you have all the pieces installed. Please see the U69 pages of the AIM for how the spark plug wires are routed and how the ignition shielding is installed along with all the clips that were added at St. Louis.

Yes the clips on the oil pan rail are orange. They were installed at the engine assembly plant before engine paint. They didn't get a lot of paint, just like the oil pan. The bottom of the oil pan got almost no paint.

[James H.]

Re: 1970 LT-1 Ignition Shielding

OK, I got it.

Thanks guys!

[James H.]

Re: 1970 LT-1 Ignition Shielding

Another question, Sorry of this was previous answered, but I could not find it....

Someone here told me or I read... at some point in production, the front shielding was not installed by the factory. Here are my questions related to that....

1) was the difference that there was NO front shielding installed at all on either side? (maybe not because all 4 inners seem to be there in the AIM)

2) was it only OUTER front shielding that they stopped installing, but the rear inner and outer was still installed?

3) at some point in productions this change was made, what was that number and how do I tell what production number my car actually was? (and I do have the tank sticker)

4) anything else I might need to know would be appreciated.

Thanks

Jim

[Terry M.]

Re: 1970 LT-1 Ignition Shielding

Another question, Sorry of this was previous answered, but I could not find it....

Someone here told me or I read... at some point in production, the front shielding was not installed by the factory. Here are my questions related to that....

1) was the difference that there was NO front shielding installed at all on either side? (maybe not because all 4 inners seem to be there in the AIM)

2) was it only OUTER front shielding that they stopped installing, but the rear inner and outer was still installed?

3) at some point in productions this change was made, what was that number and how do I tell what production number my car actually was? (and I do have the tank sticker)

4) anything else I might need to know would be appreciated.

Thanks

Jim

Jim
1) My favorite asnswer: You need to purchase a copy of the 1970-72 TIM&JG (known as "the judging manual"). It will answer this question and has pictures for those of us with better visual aquity than verbal comprehension.

Short answer is that early 1970 had full box around the distributor and four shields over the spark plugs. Later 1970 had a one piece shield over the distributor and only the back two spark plugs on each side had shields.

2) More terminoligy: What you are calling inner shields are HEAT shields. What you are calling outer shields are IGNITION shields. I THINK. The pictures int he AIM would clarify this for you so that we would know what you are talking about.

The heat shields are there for ALL spark plugs for small blocks 1968 to 1972 and beyond. Probably before too, but I claim no knowledge of C2s.

3) Sometimes production number (or serial number) is given by the VIN -- on the windshield pillar on driver's side). Sometimes it is given by production date -- generally given by the date on the trim tag above the upper hinge of the driver's door. The date follows the word CHEVROLET at the top of the trim tag. Tell us the letters yopu find there and we will decode it for you.

Off the top of my head the change point is around S/N 12,000, but I do not have my TIM&JG at work so I will defer to someone who has one at hand.

4) Buy the TIM&JG and see if you can find a chapter close to you and join up. With the virus not too much is going on by way of events, but once this passes attend whatever events they have. In the mean time there are virtual events for you to learn from. There is a whole world of knowledge just waiting for you. Drink from the well.

[James H.]

Re: 1970 LT-1 Ignition Shielding

Terry,

On your suggestion, I did buy the judging manual and i have it.

Sorry about the terminology, but I was using what came on the packages from each reproduction part I purchased.

I have 4 heat shields installed, so I am good there.

After Chevrolet on my door pillar trim tag is G14. so it looks like July 14, 1970. My S/N is 194670S415323 (I don't know how this correlates into production number)

In 1987 when I purchased the car, most the shields were not on it, but it DID have the larger shield surrounding the distributor, with the removable top, and that looks very original. I believe that is "early" production.

I believe the early production distributor shield is correct, but the question is... should I have the front and rear "ignition shields" installed or ONLY the rear ignition shields, based on my production number?

Thanks

Jim

[Terry M.]

Re: 1970 LT-1 Ignition Shielding

Terry,

On your suggestion, I did buy the judging manual and i have it.

Sorry about the terminology, but I was using what came on the packages from each reproduction part I purchased.

I have 4 heat shields installed, so I am good there.

After Chevrolet on my door pillar trim tag is G14. so it looks like July 14, 1970. My S/N is 194670S415323 (I don't know how this correlates into production number)

In 1987 when I purchased the car, most the shields were not on it, but it DID have the larger shield surrounding the distributor, with the removable top, and that looks very original. I believe that is "early" production.

I believe the early production distributor shield is correct, but the question is... should I have the front and rear "ignition shields" installed or ONLY the rear ignition shields, based on my production number?

Thanks

Jim

With the box distributor shield (which is what you have) use all four spark plug shields. I may have been wrong about the change point from the box shield to the one piece. As I said I don't have my manual with me, but July 14 sounds late to me for the box shield. I'll look when I get home and update.

[James H.]

Re: 1970 LT-1 Ignition Shielding

OK, Thanks Terry.

The manual says that From about 1970 SN 12,800 through all of 1972 production the distributor shield is one piece. So it looks like prior to SN 12,800 the box shield was used and from what you are saying all 4 plug wire shields would have been used too.