1970 LT1 - frame restoration

[Stephen L.]

Hi all - as this is my first post, i'll trouble you with a brief introduction:

- have never owned a corvette in my life...that is, until last week - after struggling between a project lt1 and driver lt1, i liquidated the kids' college funds and got one of each!

- why the LT1? - because first and foremost i drive my cars - have never showed a car, and have always tended toward the highest performing model - the lt1 seems to fit into this category - current driver is a pantera - and while i know the 2 will drive differently, i am excited to see how the lt1 does

- 70LT1: the first is a project - I have never done a project before - most of the cars I have had were drivers that appreciated continual work

- the 70 will require a frame off restoration, as it deserves one - the car's engine is nearly 100% stock from what I can tell from the outside, and has been rebuilt with just dyno time on it - the transmission is also freshly rebuilt

- the rest of the car is covered in spider webs for the most part, some grass and mud clumps here and there, the interior is shot - but, the frame is suprisingly solid

- as importantly (it appears), the car enjoys a tremendous amount of documentation.

- the driver lt1 is a 72 - both cars are t-top coupes, btw - the 72 is what i believe you would call a survivor - mechanical work has been done to all the major systems, but as needed and over time - it appears to be bone stock and also has a tremendous amount of documentation.

The question: I curious to understand what is the proper way to restore the frame from the perspective of renewal - that is, can it be galvanized and then painted? (know that is not factory correct, but in this instance is that acceptable?) - can it be powdercoated? - or must it be primed and painted? - and in whatever case, what is the correct color and finish?

If there are resources I should be turning to or searches I should perform prior to troubling you all, please let me know!

On a final note, I took the chrome molding off of the right rocker and found a series of numbers stenciled there - they appear to be part numbers, but it seems odd that they would be stenciled and not stamped?? - at any rate, it appears precisely in one of the areas with surface rust - is there a way to remove the rust without removing the stenciling, or does this matter because either it is some after markety thing or can be replicated (although i am not sure i can read it all at the moment) - thanks!! stephen

[Jack H.]

Before...

you get too far into these 'restoration' jobs, you ought to buy/read the basic NCRS judging documents: (1) Technical Information Manual & Judging Guide (for your year cars), and (2) NCRS Judging Reference Manual. They'll answer a LOT of questions for you plus acquaint you with the rules of the road.

For instance, 'Survivor' is a term used by the 'competition' (NCCB/Bloomington Gold). At NCRS we have a very similar award recognition category called Bowtie. We judge cars in two categories: restored and unrestored and Bowtie applies to unrestored cars.

A car can only compete ONCE in its life for the Bowtie award and 'tinkering' with it (restoration/repair) HURTS the car's chances to achieve the award! It wouldn't be the first time a new owner bought an 'untouched' car, jumped in to fix/spruce up this/that aspect of the car and wound up taking a turn down a one way street away from recognition in the unrestored car category, FOREVER...

The question you asked about the numbers on the frame are what we call a 'stencil'. Frames were supplied to GM from an outside mfgr and the PN was painted on via a stencil. That plus other 'marks' painted on the frame are looked for/verified during judging....

[Patrick H.]

Re: Before...

In addition to what Jack said, seriously consider having an NCRS member very knowledgeable in 70-72s inspect the car(s) and give you an opinion. We've all seen countless errors made on cars because the owner wasn't familiar with the nuances of a particular year or option, or aspect of originality. You don't give any information in your profile, so I can't suggest anyone since I don't know where you are.

You have two very nice cars. I hope that you can find someone to teach you about them before you do anything else.

And, take countless digital pictures of the cars at this point. Put the cars on a lift, and shoot away from below too. You will value those pictures as you need to refer back to something. I keep a couple hundred pictures of my 72 on my computer for just that purpose.

Patrick

[Chuck S.]

Stop!!!...Wait!!!...

Before you do ANYTHING, learn everything you can about 70-72 Corvettes. If you don't, you'll regret some of the work you'll do before you learn better. Also, if the car is running, drive your 70 to find out what needs restoring.

"If there are resources I should be turning to or searches I should perform prior to troubling you all, please let me know!"

Start your education with the C3 Reference Library in the NCRS Store...This collection is not complete, and a few of these you won't need:

https://www.ncrs.org/store/shop.cgi/page=C3.Library.htm/SID=1188836202.24613

Attend NCRS meets and compare what you've observed on your car with cars being judged and original cars on display. Clean up your car using only mild solvents sparingly and Simple Green or other strong detergent...take particular care NOT TO REMOVE any chassis or body markings. Then have the car judged...this will provide you with another list of things that will need to be restored or changed. Sometimes, depending on the car, less restoration is better than a frame-off.

Galvanizing the frame...bad idea; I assume you're talking about hot dip galvanizing. It will change the metal surface texture, and it'll be next to impossible to get paint to stick to it...and that doesn't even consider the cost. Powercoating once was frowned on, but more people are weakening on this point...I personally wouldn't use it on a Corvette I was restoring. It's time to quit picking up Super Chevy at the supermarket...some of the resto tips you'll get there are good; others should never be used on a collector car. JMHO.

[Patrick H.]

Re: Stop!!!...Wait!!!...

Chuck,

You're starting to sound like Jack H.

I'll be interested to see how the owner responds. In my experience, 75% of the time we make posts asking them to stop and learn, but then they never respond, join CF and start blasting and powdercoating everything in sight.
Nah, I'm not pessimistic.

Seriously, I hope he listens. I'd be happy to review the cars with him if he's anywhere close.

Patrick

[Stephen B.]

Have them judged in current condition

Why not just have the cars judged in their current condition? So much is learned. When I had my '70 350/350 roadster judged the first time at a chapter meet, I let it be judged with aftermarket sway bars, etc. on it. I received a little good hearted teasing from some of the judges, and I informed them of my long term intentions of improving the car.

[Alan Drake]

Re: Have them judged in current condition

Everyone has given you the best advice - and I bet some learned the hard way!

If you just desire to clean take a look at Ridrust (.com) - a rust cleaner which will leave the paint marks, but clean the rust, it may be just what you need for the frame area.

DO NOT through anything away, mark it and save

[Chuck S.]

Re: Stop!!!...Wait!!!...

Thanks for the compliment, Patrick.

Sounding like Uncle Jack, and many others here is a high aspiration. But, in my case, I think it may be the hazard of being a technically-minded pedantic in a potentially technical hobby. Actually, after I posted, I wondered if I had repeated what you had said.

Getting some help to check the numbers would be a good idea before he sinks a lot of money into restoring a car that DOESN'T deserve it. Many of us have lucked out on that first uneducated purchase, but many haven't been so lucky. To his credit, Stephen has made a good first long stride in his journey...He has a member number.

[Jeremy D.]

...or send the parts you don't want to me!!! *NM*

[Patrick H.]

Re: Have them judged in current condition

Note that while I do like Ridrust for certain things, I have found it will remove any yellow dichromate finish, will eventually remove black or gray phosphate, and may peel off chrome if there is any corrosion on the part.

But, if used judiciously, it can work quite well.

Take a look at my car frame below. I really thought about trying Ridrust until my experience with smaller parts made me rethink that idea. 3 Top Flights and a Bowtie Award later, I'm not too worried about it any more.

Patrick

[Dick W.]

Re: 1970 LT1 - frame restoration

Stephen, why not bring it to Waco for the Regional. Good place to find out what is correct. Most of the same judges that would judge the car at the National Convention will be there.

[Patrick H.]

Re: Stop!!!...Wait!!!...

Member Number - $35
LT-1 coupe - $35000

Understanding that we're not joking when we talk about taking it slow and getting advice ..... Priceless.

PH

[Stephen L.]

Re: ...or send the parts you don't want to me!!!

thanks all...very, very good advice.

one potential problem here is that there are 2 cars at issue - one is a project (as in engine is on a cart, tranny is in a box and there are various vice grips holding bunches of wires together - so...this car is not driveable...period.

the other car is a driver and currently drives - although it is very original (probably not by NCRS Bowtie/BG Survivor standards), it is also a terrific car with everything it needs (including all important documentation).

so, the first step is for me to post separately about each car - it was always my intention, but I interleaved them for purposes of the introduction.

next - while I am a rank ameteur on most things cars and everything corvettes, i do enjoy researching and have done a fair amount - in addition, prior to buying both cars (and each was bought sight unseen) I did have them inspected - one car by Chuck Berge from VA, the other by Bob Cook from Dallas - I found them through the research - they have unreservedly endorsed each car as the "real deal" - so, while I could never hope to defend that statement, I certainly rely on their judgement.

i very much take to heart the "good intentions" can lead to an ignorant mistake - and that is something I DO NOT WANT TO DO - for this reason, you will see lots and lots of posts from me - asking how things come apart - what product to use for what item - "proper" way to restore things - while I like Super Chevy (and a whole bunch of other things), I realize they have their time and place, neither of which relate to the project at hand.

So, to sum up what I got from the threads below:

1. - the stenciling on the frame resulted from a toll mfg'er - this like many of the other markings are unique and represent the history of the car and they must not be destroyed in any way - so...much like the archeolegist, leave the blaster at home and use a lighter touch so as not to destroy the record - ok...got it.

2. - there are products out there that will kill rust and not paint - understood and will look into that - one follow on: given that the frame gets primed and painted, was the stenciling originally on the bare frame? - and once it gets covered up, how do judges "judge" it when they can't see it - via restoration photos?

3. - educate myself - indeed...hence the membership and the questions - there have been good suggestions for reference materials and I will get those - some, in fact, came with the 70 (the 72 (the "driver") comes tomorrow) - a compendium of NCRS technical articles (perhaps the judging rules/requirements) - and a photocopy reproduction of the manual by a company called mid-america corvette (there may be others...lots of boxes stuffed into the 70 - assume parts, but who knows, maybe more literature

4. - you guys have a good sense of humor - Chuck has been busting my beans but extremely generous with his time - already owe a beer per a different thread - Patrick had me laughing out loud with the credit card spoof - so OK - learning yes...stop and wait, learn and then do...maybe...how about this approach...chug along (slowly) and stop, wait and learn prior to each step, without stopping the whole journey - after all, I must not be the only guy that blew off homework and watched the sunday night movie...

Dick - not sure how far people travel for shows - did you mention Waco because all the people just go...or did you have a premonition that I live in TX - Houston to be more precise - either way, sounds like a good option for the 72 "driver" - hopefully Chuck Berge will be there and what he says there will match his inspection report!! So when is it...and where exactly? - maybe a web link?

Speaking of Houston, maybe some of the experienced folks that would like to mentor yet another amateur are in or around?

Patrick - is there a deruster you do like for "everything" - Orison? - the one that uses beet juice? - the one that needs a pump and has to continually wash over the part? - other?

OK - enough of 47758! - being a new guy, i should pipe down...

[Chuck S.]

Busting Your Beans!!!...

"...while I like Super Chevy (and a whole bunch of other things), I realize they have their time and place..."

Did I have you pegged, or what???!!!

If you live in Houston, and you don't go to Waco...you're under-motivated. I'm not going, but I live 12 hours away!!!

Frames: The frame cleaning/painting procedure is in the archives at least twice that I know of, maybe more. Learn how to use the search feature effectively; most of these questions have already been asked a zillion times...whenever you precede your question with "I tried searching the archives...", you'll really impress us, and save yourself from getting grump-chewed. You just think I've busted your beans! Nah, only kidding you.

Essentially, the fabricated frames were cleaned and degreased in a very hot solution, and then were painted upside down over an open pit with hoses while they were still hot.

Excess paint ran off into the pit, and it was recirculated through the hoses again. All frames do not have runs, but if runs are present, they will run "up" as the frame is installed in the car. The frames were stenciled later while stacked upside down...the stencil includes the frame part number and the date of manufacture.

Stencils are not visible with the rocker molding installed, and are not judged. If yours is still visible, it is valuable documentation. If you later decide to sandblast the frame before repainting, record the position of the stencil exactly, so you can return it to the original position. Pre-cut stencils with your information can be ordered from various Corvette vendors.

[Patrick H.]

Re: Busting Your Beans!!!...

"Stencils are not visible with the rocker molding installed, and are not judged."

Wrong-o, Chuckie.

There is a line item on the judging forms just for judging the stencil. We regularly use mirrors to find and evaluate the stencil. Can't let some silly piece of anodized aluminum stand in our way!

He should be sure to photograph it (didn't someone suggest that earlier?) and reproduce it accurately. The companies that reproduce them will make an exact duplicate if you ask. In fact, they prefer that when possible.

Patrick