Need some numbers help

[Dale S.]

Re: Moral to this story

Another moral to the story. A friend of mine went by the body shop his car was being painted at on Sunday(this was a place that was kind of back alley, the guy painted at a larger place). Low and behold the gate is closed but the shop door is open and the motor was half out of the car. This was before cell phones, he went to the 7-11 and called police. It was the painters brother in law. Photo every part of your car and document the serials. I have photos of most of the numbers on my car. Digital camera's are great, you can erase until you get it right. Dale

[Mike Cobine]

In sort of same situation once

I had my '68 in the dealer for work long ago. A problem came up and a dispute. My attorney said, take a camera, photograph it completely, then pay the bill and leave immediately. Do not delay. Do not argue price. That is what court is for later.

The photos there show the state it is in so they can't say you changed it later. You get it out to prevent anything happening to it.

They may just be well-meaning idiots, or they may actually know something, but they are not communicating that very well and it is time to leave.

One thing I learned long ago about cars, if they were running once, then those parts should be running still, unless something has happened to change that due to breakage or wear. Wear is slow, but you will notice changes. In your case, plugs were fine your last tune up, now they hit? Not likely from wear.

This would mean breakage and breakage is usually violent. But the only things can could break to make them hit are the rods, crankshaft, wrist pins, or pistons, and then the engine shouldn't be running as breaking enough to tap the plugs should hammer like crazy.

Possible that they installed the wrong plug. A R43TS is the standard plug, but if they went with an R43TSX or R43TS8, then the ground would be extended out a bit more and might hit. Or if the builder changed things so that they needed an R43T to clear and forgot to tell you, then that could be a problem.

Best to get it home and find out.

[Tom Jumper Chevrolet]

Re: In sort of same situation once

This is John Crowe from Tom Jumper Chevrolet. Let me step in here before we are bashed to death and stop some of these horror stories. mark brought his car into our service center. We have on staff fully certified techs who work on nothing but corvettes only after GM training and internal training. we honor ourselves in offering the best corvette experience OF ANY service center you could take your corvette. i put David Fulcher on this vette. Many of you may know David...if not do some research and you will see the quaility of tech we have here.

issue:

Mark has from what we are told had this car for 2-2.5 years. When he brought it to us it would not even run. we had to push it into the service area. when we got it into the service area and cranked. it ran very rough and would not rev above 3500 rpm. Mark informed us the car would never rev above 3500 the entire time he has owned it.

upon inspection the car has small plug heads (r44ts)

david took out the plugs and inspected them again....again 1-2 of the plugs had the gaps closed (these were just gapped)

david then proceeded to do a bore inspection looking for the item that closed the plugs.

what he found was that the piston were domed style pistons.

I then called mark, inquired about the cars history and performance. I then told him what we had found upon inspection. he asked why, and i told him that many times this is done as a forgery, but i was hoping and thinking this was not the case with his.

so heres what we have.

1 the heads are of the correct casting (date code unsure) and at present has small plugs in it

2. the pistons are of a large domed variety

3. we have been very upfront and honest about every item we have encountered

If anyone would like to contact me with or for inforation please contact me at john@johncrowe.com or calling my direct line. 770-351-2604

but please remember...there are honest dealers out there

[Chuck S.]

Thanks For Your Response, John...

Since you willing put your good name on this situation before a good part of the Corvette world, I believe Mark (any several of us as well) can relax and he take his trip without worrying that the car will have parts exchanged in his absence.

I presume David's borescope examination showed minor contact damage to the domed pistons directly below the plugs...Do you'all have a recommended solution short of changing the heads, such as different plugs, different gaskets, indexing, etc.?

[Richard S.]

Re: In sort of same situation once

John,
Thanks for posting the facts as you understand them to be. Hopefully your initiative will lead to a satisfactory resolution of Mark's problems with his Corvette. I'm sure you can understand that the posters who responded to Mark's original posting did so on the basis of the facts posted by Mark as he thought them to be at the time. You have conveyed a very professional and responsible attitude in your response.

[Mark #28455]

KUDOS for your response!!!!

Takes a person with guts to jump right in and explain the situation! My hat's off to you!

[Tom Jumper Chevrolet]

Re: KUDOS for your response!!!!

Heres what i have determined so far.

1. the car has r44ts plus put in it...should be r44t the ts plus is almost 1/4 inch longer than the t. The wrong plus were in it. I think replacing the 44ts plug with the 44t plus will fix the issue there.

2. are the domed piston correct for this year car 71 model

So many times things can be fixed if given time and we take the higher road and not jump to conclusions. This was a situation turned ugly when it shouldnt have. Ive spoke to Mark and expressed to him my concern of our business name being used until we couldnt come to an agreement we all were happy with. hopefully we are on the path to serving another happy customer. always remember its not about being right everytime, but doing right everytime that counts

[Mark Carlisle]

Re: KUDOS for your response!!!!

I started this thread one day before going on vacation, so I have not looked at it in a while. I asked my service advisor to look at the thread to see if it could shed some light on my problem. I was embarressed when he told me the thread had basically turned into a Tom Jumper bashing thread. Hence the post by John. It was never my intention to bash the dealership. The only reason I mentioned Tom Jumper was thatI consider Tom Jumper the premier Corvette dealer/service dept. in the south. My service advisor and I had a difference of opinion on how some information had been passed. We have worked past that and are on out way to figuring out what is wrong with the car. Both the service advisor and mechanic have worked hard to figure out a solution. Out of the millions and millions of cars GM has made they made less than 2,000 LT-1 Corvettes. I don't expect Tom Jumper to know everything about the car instantly. That is why I started this thread. I wanted to get some expert LT-1 advice.

I have nothing but positive things to say about the efforts of all three people I have talked with at Tom Jumper. They all are trying to find a solution to car's problem.

All of my post on this forum have bee positive experiences up until this point. Unfortunately this thread has turned into something I neither expected nor wanted.

I am requesting that everyone who posted anything other than constructive information about the LT-1 engine delete their post. Thank you.

Mark Carlisle

[Mark Carlisle]

Re: KUDOS for your response!!!!

Back to the LT-1. Does anyone know if this car is supposed to have domed pistons?

[Joe L.]

Re: KUDOS for your response!!!!

John-----

Domed pistons were NOT used for 1971 LT-1 engines. The pistons used for 1971 LT-1 engines were forged aluminum of GM #3991484 or 3997714. Later, these became GM #336754 and, later, yet, GM #474190. These pistons are FLAT TOP style with a single, elongated valve relief.

The GM CASTING #3973487 cylinder heads, which, incidentally, were produced in both 1.94"/1.50" and 2.02"/1.60" valve size (the latter size used for ALL LT-1s) have 75 cc, nominal, combustion chamber volume. Usually, these heads can be used with "domed" pistons but not ANY domed pistons. The installed camshaft can have a large affect on this, too. Normally, the original LT-1 camshaft, GM #3972178, could be used with these heads and domed style pistons equivalent to the 1970 LT-1 configuration. This should produce an APPROXIMATE compression ratio of 10:1 as compared to the 9:1 compression ratio found on all 1971 LT-1s.

The R-44TS spark plug, GM #5613302, was, at one time, the GM-recommended spark plug for 1971 Corvettes with LT-1. In 1974 GM changed that recommendation to the AC R-43T spark plug, also known as GM #5613354. However, I believe that either the R-43T or the R-43TS will work fine in a 1971 LT-1 assuming that the engine is of stock internal configuration. Domed pistons don't constitute stock internal configuration for a 1971 LT-1, though.

[Rick S.]

Re: KUDOS for your response!!!!

Sounds like things are on the right track. Keep us posted on the outcome Mark

Rick

[Mike Cobine]

Re: KUDOS for your response!!!!

John, if you are looking at this thread today, you can see that Mark has deleted many of his posts. Our comments were based on information here, not out to bash anyone. His initial comment was it was not running right. This is quite different than having to be pushed into the service bay.

1. As Joe stated, the R43TS is the original plug. However, tht is for stock configuration. As many on here have stated, original plugs were often too cold, so the R44TS is a good choice for most street driving.

2. The '70 LT1 used a notched dome piston with a .10 inch height and 1.41 cc dome, not all that big really. The '71 (Mark's) should have a flat with one notch piston, the notch being 3.4 cc, and the depth of the notch being .180 inch.

Now to the fix. The R44T or R43T are shorter than the -TS version and may clear. If so, he is probably ok but on borrowed time if he begins to really utilize the 6500 RPM redline of the LT1. Removing the heads and using two head gaskets may also help, but again, that isn't the best. Since the heads are already a 69.5 cc volume, there isn't much hope of replacign with heads with a larger chamber.

The only real solution that is 100% is to replace the pistons with the correct configuration.

As to my situation, I took a '68 in for alignment of the rear suspension after rebuilding the entire rear suspension. The charge given when I went it was $16 + tax (so it was a long time ago). When I picked it up, the bill was $170. The work was finished and the car was parked on the lot in back.

I left to call my attorney after I couldn't resolve it there and he sent me right back to get the car. When I arrived to pay the bill, my car was now in the service bay with the hood open. They did not have an answer as to why it was back in.

As you can see, I may have narrowly adverted a very bad situation with a dealer, so while I know there are good dealers out there, I have seen some who do not always have good guys in them.

You are obviously aware of the same or you would not strive so hard to keep your reputation so good.

Mark expressed that he had the feeling of having to defend his car against you and in a situation where the owner does not feel comfortable, the only fair thing to do for all sides is to remove the car. This way, you cannot be blamed or be guilty and he can feel that his car is not subject to any problems.

Good luck in getting this fixed.

[Tom Jumper Chevrolet]

Re: KUDOS for your response!!!!

Update:

Car is running. we removed the plugs that were in the engine, replaced them with r43t plugs and it cranked, idled and most importantly reved over 3500 which it has not been able to do before.