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Old 06-13-2012, 04:19 PM
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Default 71 Pontiac Lemans

I have been lurking on this forum for almost a year now learning an amazing amount of information from all of you and your impressive builds. Thank you for making the effort to publish your experiences, it has been a huge help to me.

To show my appreciation to the LS1Tech community I am starting this build thread for my project to share what I have learned and accomplished with the hope that others can learn from me.

First, some background. I am 52 years old with a mechanical engineering degree. I worked at the Boeing airplane factories for many years where I learned a lot about airplane manufacturing, materials, fasteners, etc. I have also enjoyed my woodworking hobby for many years, for the last several years I turned that into a cabinet-making business. So I am good with my hands making things and figuring things out.

I have had two car projects in the past. The first during high school was a 1978 Plymouth Volare with a V8 and four speed (I know, sounds lame now but Dad worked for Chrysler and I ordered it new with the features I wanted, paid cash saved from after school jobs). I did the usually hot rod stuff, four barrel carb, headers/exhaust, wheels tires, etc. Learned a lot about cars from this effort, especially from my mistakes! Second car was several years later, bought a 1972 Datsun 240Z where I changed carbs to a Holley four barrel, reupholstered interior to black and did a crude red paint job.

Fast forward to last year; kids are teenagers, have time/money/place to do another car project, and divorced so no one to justify spending money to. My 18 year old son and I got to watching Overhaulin episodes on Netflix last year, he would keep asking me if we could do something like that. I initially wasn't real crazy about it, but the more I thought about it the more I liked the idea.

So last summer went searching for a project candidate. Looked for mostly GM (easier to get parts), and something cheap to conserve other money for upgrades. I ended up buying a 1971 Pontiac Lemans convertible. Previous owner and his dad bought it in pieces 10 years ago, it sat in their barn untouched until I bought it. He was asking $2500, I paid $2000. He said "floors are solid", I soon found out as many of you have what a misused phrase that is . . . Being a midwest car it has rust issues, some I was aware of when I bought it, some discovered later.

Pictures below show us bringing it home:



I also got bumpers, front sheet metal, two sets of doors, seats, most of the exterior trim, etc.

Plan is to do a mild Pro-Touring build with LS1 power, and hopefully get my kids involved now and then so they can learn about cars with me.

We started this build last fall and have worked on it steadily since then making a significant amount of progress. I thought I would post an update every few days covering all of my progress made between then and now and then hopefully keep it updated. I will try to include details and part numbers as much as possible.

Thanks for reading.
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Old 06-14-2012, 06:40 AM
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Default Deconstruction Begins

Deconstruction started as soon as we got it home. I took the advice of others and tagged and bagged removed parts and took pictures as much as possible.

Since it's a convertible I added bracing to the interior to keep it folding up like a taco while it was off the frame. Since my welding skills were zero at that point and steel can be a little pricey I looked for materials that might work and come upon electrical conduit which is relatively cheap and easy to work with. I attached these to the car and to each other with 5/16" bolts. I tried to triangulate the bracing as much as possible to keep the body from flexing too much, it seemed to work really well and kept it rigid for months.




With that done I was ready to remove the body. Removing the body bolts proved to be quite the chore due to rust, I think only one or two came out without damage. Some snapped in the middle, some the welded cage broke off. Those bolts I wasn't able to get off I just cut through. I tried soaking them with PB blaster without much luck. Several of them had rusted to the point they were less than half their original diameter. Once the body bolts were out it was a slow and careful process using wood and concrete blocks and a floor jack to raise the body high enough to roll the frame out.




To sandblast the frame and keep the mess outside I rolled it outside in front of my shop. I bought an Eastwood blaster which I was very happy with. The seller of the car also sold me his old 80 gallon air compressor which was very helpful supplying the large quantities or air required by the blaster.




The frame was in pretty good shape, mostly surface rust with the exception of some rusting out around three body mount holes. I fixed that with the repair "washers" some of the restoration companies sell.

To finish the blasting I removed all of the suspension, brakes, steering, and remaining hardware and tubing. To refinish the frame I used all Eastwood products; Rust Convertor first, then Rust Encapsulator, then two coats of epoxy primer and two coats of their epoxy chassis paint. Internal Frame Coating was sprayed on the inside of the frame. This picture shows the frame refinished and the caster supports I made to make moving the bare frame around easier.

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Old 06-14-2012, 07:30 AM
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Cool project you have there sir, I take it your going modern LS power? It'll be fun for you and your son to build together, gl!

-SS
Old 06-14-2012, 08:03 AM
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I work on 737' s and have almost finished my Ventura LS swap. The aviation experience has helped out a bunch for wiring and plumbing. Good luck.
Old 06-14-2012, 09:14 AM
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Good start on saving another Classic Car.. keep up the good work and keep them pictures and posts coming.

Looking at the car on wood and block's brings back images of what I did,.. I used the same method, I did it by myself.. running from back to front and side to side until I got it up and the rolling frame out !! LOL

BC
Old 06-15-2012, 05:54 AM
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Good to see another Tin Indian here. My car is very similar, be happy to share my experiences and parts lists. If you need pictures, don't hesitate to ask.
I am following the mild Pro-Tour set up with brakes, control arms and coil overs at all corners. I have designed and prototyped upper and lower mounts for the A-body and have patterns if you are interested.
Old 06-15-2012, 08:46 AM
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oldgoat69: Thanks for your very generous offer to help. I'm actually done with the frame, it has new suspension, brakes, and the body is back on the frame. I hope to get this thread caught up in the next week or so with all my progress over the last several months.

bczee: Your thread among many others was very helpful in my planning stage. I may have gotten my body support method from you. I also did that by myself, it was a little nerve racking but actually worked out well. My kids don't help me full time, it's when their schedule and interest level allows. Probably 90% of the time I am working by myself.

74ventura: I worked in the Boeing Everett plant for several years as a trouble-shooting engineer so I spent many hours looking at schematics. This did prove very helpful when I had some issues getting the engine going recently.

hotrodscrap: Yes, LS1/4L60E from a 2004 GTO. I will document that in a future post, should make interesting ready.
Old 06-16-2012, 11:43 AM
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Now that the frame was done it was time to put suspension and brakes on. The first thing to go on was an updated steering box. I learned from the Chevelles forum a popular and cheap upgrade is to replace the original slow steering box with one from a mid 90s Jeep Cherokee. Surprisingly it bolts right up just like the original, the only thing that has to be done is to remove the Jeep pitman arm and replace it with the original A-body one. The advantage of the Jeep box is a faster gear ratio. You can see the steering box installed in the previous post about the painted frame.

Being the geek/engineer that I am I do a lot of research before I buy something, especially if it's expensive. My research into suspension led me to get the Stage 2 Plus Touring Suspension package from Savitske Classic and Custom. As a lot of you have also found out, Mark Savitske literally "wrote the book" on muscle car suspension upgrades (you can find it on Amazon) and is extremely helpful and enthusiastic with questions. The package is a bit of a hodge podge of suspension bits from different vendors, but Mark apparently has searched the industry and picked the best component of each type that work well together. The package solves the suspension issues these cars come with and work more efficiently with the upgraded brakes, wheels and tires these cars get. After dealing with all the rust I was also motivated to get the stainless suspension bolt upgrade. In fact, I use stainless hardware as much as I can for everything underneath the car and in the engine bay. Picture below shows the suspension bits being organized for installation.



The picture also shows the brake package I got from Stainless Steel Brakes. I ordered package A123-1A for the front and A125-26 for the rear. The fronts appear to use the stock design for things like the brackets, shields, bearings, etc. They are designed to use the stock spindles so I got some new spindles also. The calipers are pretty cool looking - large aluminum billets with a brush finish and SSBC engraved and them. Different powdercoated colors were an option, but I just got them in the natural finish.


I gave my daughter the honor of putting the first new part on, the rubber jounce bumper in the frame:




Ove the course of the next couple of months the suspension and brakes were installed. The design of the SPC upper arms requires some grinding for clearance on the frame bracket; my son enjoyed creating sparks while he did that:




I also decided to rebuild the rear end. In doing so I found to my surprise a 12-bolt Chevy rear end. This was a plain Lemans with power drum brakes and no A/C so I'm I don't believe it came this way. I am guessing a previous owner swapped it in the past. It was leaking around the axle seals and I wanted to replace all the bearings so I bought a rebuilt kit and started tearing it apart. On teardown I found the races on the axles were pitted so new axles and studs went in.



Some say to leave rear end rebuilds to the experts, but I thought I would give it a try. One of my goals on this project is to do as much as possible ourselves. It's not so much to save money although that's part of it, it's for the challenge and learning experience gained with doing it myself. I got it back together as best I could, if it ends up not working out I can take it to a shop to get it redone. Plus it has a 2.7 gear and is non-posi so I will probably want to upgrade those in the future also. It's good enough for now. This picture shows the rebuilt rear end going back in with the new suspension and brakes (my son and his friend, high school football players are handy to have around for jobs such as this, that rear end is heavy!)




The final shot of this post shows the new suspension and brakes mostly installed. I also bought and installed the factory braces that go between the rear upper and lower control arm mounts of the frame. All of the work in this post took place over 2-3 months last fall.



Since then I moved the rear calipers to behind the axle, it worked out better that way for the brake line and emergency brake line hookups.

I STILL haven't installed the triangular rubber bumpers that go into slots on the rear axle (you can see them in the picture on top of the spring pockets), any suggestions on how to get them in?
Old 06-16-2012, 12:32 PM
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Neat looking build so far, and nice selection of parts too! For the axle bumpers try some silicone grease and either work them in with a screwdriver or position them and hit em with a heavy rubber mallet.
Old 06-16-2012, 12:55 PM
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LOL, I have that same welder
Old 06-16-2012, 04:08 PM
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I used dish soap on mine with very little persuasion with a screwdriver and they popped right in.
Old 06-19-2012, 08:27 PM
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With the frame in pretty good shape I turned my attention to the body. Of course I found the floors to be in worse shape than I thought. As I tore into it I found amateur repairs such as plates tack welded in and even a repair under the driver's feet composed of foil tape and Bondo. The front and center floor braces were pretty much shot, and the area under the rear seat had significant issues also. The rockers were fortunately mostly intact, just some small holes near where the braces attach. I started on the driver's side by cutting the damage back to good metal. I bought repair sections for the two sides driver's and passenger, the section under the rear seat, and the front and rear braces. This picture shows the driver's floor section fitted in place with clecos.



At that point my welding skills were very much in the beginner stage, especially with sheet metal. That fact and my desire to do as much as I can myself led me to investigate some alternatives. After much research I decided to use 3M Structural Bonding Adhesive. Structural adhesive has been used for many years in the factory, in some cases for the entire car. My 96 Chevy truck has the hinges bonded to the cab structure with no problems. I fit the panels with a 1" overlap, ground the mating pieces to bare metal, applied the adhesive to both sides and installed with stainless steel blind rivets as "clamps". I thought it came out great, for me better and easier than welding. It doesn't look as slick as smoothed butt welds, but the top will be covered and I don't care what the bottom looks like; I am not trying to build a show car. I don't think I would have done this with a unibody car but with this car having a full separate frame I feel comfortable with it.

Access to the driver's and passenger side floors were fairly easy with the body on blocks, but installing the new floor braces, repairing under the rear seat and trunk areas was going to be more difficult. I looked into getting a rotisserie but didn't want to spend money for something that would get used for a short time. I again did some research and discovered the wood "rolltisserie" idea on a few other forums. My version is shown below.





It may look hokey but it actually worked really well, was very stable, and made working on the floors much, much easier. I had my son help me rotate it up and down, but I probably could have handled it by myself; it was that easy. The rolltisserie is attached to the cowl boxes in the front and the bumper bracket bolts in the rear.

I continued cutting out bad metal from the floor and trunk areas and installed new sheet metal with the same procedure. This next picture shows how much metal I replaced. The black areas are original sheet metal treated with a rust convertor. The bare metal areas are the new sheet metal.



I wanted to blast the metal floor top and bottom to remove the remaining surface rust and prepare for coatings. I didn't want to make a mess of my shop so I make a "tent" over the rolltisserie. It worked great, but was sometimes hard to see through the dusty fog the was created inside. I wore goggles and a respirator when blasting.




Once the repairs and blasting was done I treated the existing sheetmetal with rust convertor and encapsulator. Then all areas got two coats of epoxy primer, seam sealer, and two coats of chassis paint. Then several layers of undercoating were added to the bottom.

LS1 swap coming up next.
Old 06-20-2012, 05:52 AM
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Been there done that, caught myself on fire, but that is a different story. Way more fun when the dirty stuff is done.
Old 08-05-2012, 01:06 PM
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It's been almost two months since I updated this post, I have been busy with work and summer activities.

I wanted to get the frame as complete as I could before I put the body back on it because it's much easier to work on it with the body off. This included things like the engine, transmission, cross member, headers, exhaust, etc. So that meant I needed to source an engine and transmission. I had been looking quite a bit at buying a drop-out engine/trans from a yard, buying an older Camaro or Firebird, trying to find engines and transmissions on craigslist, etc. An idea I came across on other builds that I found very appealing was to buy an entire donor car. As I did my research a logical donor car to me was a 2004-06 GTO. They have newer LS engines, nice interiors, and typically have lower miles than older LS1 Z28s or Trans Ams. Lots of salvage yards have listings on the Internet and I started to search those for a good candidate. I found a 2004 GTO with 60K miles at a yard a couple of states away.









As you can see I bought it from East Coast Auto Source in Virginia. I bought it through phone calls and emails, they were very good to deal with. They even arranged for shipping with a carrier they recommended. It arrived less than a week after I bought it.

It obviously got hit on the side, which was a plus for me. I was reluctant to buy one that got hit on the front since I didn't want to worry about what was damaged under the hood. It arrived with a broken ignition lock and no battery, after I dealt with those issues I was able to start it. It actually drove just fine (up and down the driveway).

My plan is to get quite a few parts out of this – engine, transmission, radiator and cooling fans, wiring harness, most of the interior including the dash, console, front & rear seats, and other miscellaneous bits. Then I will sell what’s left (which will be mostly body parts, suspension and wheels/tires) and cut up the carcass and recycle the metal. Based on my research and calculations I should make out pretty well with this, it will be much cheaper than buying all of the parts I need used on ebay and definitely cheaper than buying these parts new. I am hoping there is good karma here also – parts from a newer Pontiac going into an older Pontiac.

Next up, disassembly of this donor car.
Old 08-06-2012, 05:34 PM
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nice, i'm doing a build of my own on a 71 monte carlo, got the engine from a guy who did a ls transplant out of a 87 merkur. plan on doing another on my 66 goat, looking for an engine, how much did they charge for that donor car if u don't mind me asking
Old 08-06-2012, 05:47 PM
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Nice build! Now you've angered the "hardcore" Pontiac folks that think the last true Pontiac was built in '81. I say fooey to that! LS power for the win!
Old 08-07-2012, 05:52 PM
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Great job so far, good luck on the build. Looking forward to more pics.
Old 08-07-2012, 06:19 PM
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Looking good! Keep the updates coming.
Old 08-08-2012, 04:53 PM
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Thanks for all the encouragement and feedback.

I bought the GTO donor for $7000, the shipping was $400 from Virginia to Ohio. No tax on that. It may sound like a lot but I think I got a lot of parts for what I spent, and I hope to make about $2000-3000 of that back by selling what I don't use. I saw LS1/4L60E pullouts on ebay for $3000-5000, GTO seats for $1200, etc. Figuring that and all of the parts I didn't have to buy new - radiator, wiring harness, A/C system, gauges, cruise, sound system, interior bits, etc., I should be ahead of the game by quite a bit.

The guy I bought the Lemans from is a die-hard Pontiac guy. When I bought it he asked me what my plans were for it, when I told him his reply was "Oh, I'm not sure I like that, a Chevy motor in a Pontiac!" I guess letting it rot in his barn was better? I told him I would try to get the motor from a Trans Am or GTO but he didn't seem too impressed with that either. I appreciate what the restoration guys are trying to do, it's just not my thing. I've done the traditional hot rod stuff with carburetors and all the fussing that goes with it and don't particularly want to do that again.
Old 08-08-2012, 05:04 PM
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Originally Posted by fsdproject
Thanks for all the encouragement and feedback.

I bought the GTO donor for $7000, the shipping was $400 from Virginia to Ohio. No tax on that. It may sound like a lot but I think I got a lot of parts for what I spent, and I hope to make about $2000-3000 of that back by selling what I don't use. I saw LS1/4L60E pullouts on ebay for $3000-5000, GTO seats for $1200, etc. Figuring that and all of the parts I didn't have to buy new - radiator, wiring harness, A/C system, gauges, cruise, sound system, interior bits, etc., I should be ahead of the game by quite a bit.

The guy I bought the Lemans from is a die-hard Pontiac guy. When I bought it he asked me what my plans were for it, when I told him his reply was "Oh, I'm not sure I like that, a Chevy motor in a Pontiac!" I guess letting it rot in his barn was better? I told him I would try to get the motor from a Trans Am or GTO but he didn't seem too impressed with that either. I appreciate what the restoration guys are trying to do, it's just not my thing. I've done the traditional hot rod stuff with carburetors and all the fussing that goes with it and don't particularly want to do that again.
I agree, that's the reason for my swap, tired of the carb thing. As for the 7k for the donor, you're way ahead of the curve, plenty of things you can use from that and plenty to sell. I'm in Michigan so the shipping will be along the lines of what you paid, I'm looking to do the same as you.


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