1961 Impala 2 door hard top mild custom
 

Initially I started a build topic on another forum, however that site is less technical and more restoration based thus I think more people will gain from sharing information here.

The car is a 1961 Impala 2 door hard top (aka bubble top) I purchased in 1993 and drove daily for several years. Even as styles changed, my overall goal for this car remained basically the same. The only real changes to the original plan were the technological improvements that have come about in the past 20 plus years.

The basic build goals are:
• Reliable enough to drive coast to coast (power tour, etc.)
• Fun to drive
• Modern EFI reliability / drivability
• Build as money and time allow
• Do everything to this car myself excluding interior, chrome and machining.
• Look like a mild 1960’s custom with a few modern updates.


This build will be slow as I’m actually drive testing parts and ideas to ensure everything works or fits as desired before I get into paint. I also work by myself most of the time and make all the custom parts you will see me use.


When I purchased the car it was white with a teal stripe and interior with a bit of hand laid pin striping on various parts. The build plate confirms this as the original paint combination, but the car had been painted a few times in its prior life. Some point early on I decided rattle can primer looked better than faded white and the earliest photos I can find show this combination (circa 1993 or 1994). This is when the car was my daily and only vehicle which meant any wrenching I did needed to be completed in time to sleep long enough to go to school and work the following day.

These images, shortly after I purchased the car circa 1993 or 1994 were previously hosted on our former business site.

http://downivlife.com/pics/1961Impala/atlake.jpg
http://downivlife.com/pics/1961Impala/passfc.jpg
http://downivlife.com/pics/1961Impala/passrc.jpg
http://downivlife.com/pics/1961Impala/rearc.jpg

In 1997 I bought a new car the Impala was retired from daily service, but still driven and tinkered with on weekends. In 2004 I used the engine and transmission I built while driving the car daily for another project marking the last time I would drive this car until 2015.

http://downivlife.com/pics/1961Impala/emptybay.jpg



I built and helped build countless cars while this car patiently waited. Originally planning for tuned port, I stumbled into the Gen III / IV / V (LSx) engine family with flash tuning via OBD II or CAN Bus and I haven’t looked back.

After some life changing events in 2014, I pretty much stopped building stuff for other people and refocused on my own projects. I set a goal to have this car running and driving at a local show where unfinished projects, rust, primer, barn finds, crazy fabrication, pin up girls and flame throwers in the exhaust are normal. No billet parts, no silly looking 20” wheels, nothing modern looking and no cars newer than 1964 or trucks newer than 1972. In short, a purists hell and a customizers dream.


First task was a solid chassis. My suspension bushings and ball joints were shot so I purchased a set of tubular CPP upper and lower control arms that add 5° of caster to the steering. These come loaded with bushings, cross bars and ball joints. They are so complete they are ready to bolt in with everything you need minus a chassis and bit of grease.

http://downivlife.com/pics/1961Impala/CPPlower.jpg
http://downivlife.com/pics/1961Impala/CPPlower1.jpg
http://downivlife.com/pics/1961Impala/CPPupper.jpg
http://downivlife.com/pics/1961Impala/installed1.jpg
http://downivlife.com/pics/1961Impala/installed3.jpg

Next was the power plant. I had a few 5.3’s but by chance a friend found a virtually untouched 6.0 and 4L80E in a self-pull yard. Unfortunately it rained the night before so we were had to get creative to get the job done. But the job got done.

http://downivlife.com/pics/1961Impala/pulling6liter.jpg

http://downivlife.com/pics/1961Impal...ing6liter1.jpg

http://downivlife.com/pics/1961Impal...ing6liter2.jpg


The truck was a worker for sure and everything on it looked like it had been ridden like a rented mule it’s entire life – including the engine internals. I’m thinking they spent a lot of time at idle or didn’t change the oil very often.

http://downivlife.com/pics/1961Impal...rchangeoil.jpg


Close inspection of one of the rod bearings looked so nice I went Denma style and put the cap back on. It’s difficult to tell in the pictures due to the grime and cooked on oil, but the cylinder bores were absolutely beautiful and the cam looked great. I re-used the cam, rockers and pushrods then I bought a used set of low mile lifters on ebay because I was concerned with the originals being gummed up. Then I disassembled and cleaned everything the best I could with four cans of carb cleaner. Hahaha.

http://downivlife.com/pics/1961Impala/rodbearing.jpg

http://downivlife.com/pics/1961Impala/bottomend.jpg

http://downivlife.com/pics/1961Impala/topengine.jpg

While looking for a car intake I stumbled across a set of used LS3 heads which of course require an LS3 intake and offset intake rockers.

http://downivlife.com/pics/1961Impala/LS3heads.jpg


I assembled the engine with fleabay studs.

http://downivlife.com/pics/1961Impal...neassembly.jpg


A call to my friendly GMPP dealer netted a complete LS3 intake, throttle body, MAP sensor, injectors and fuel rail. In the images below I had already swapped to a fleabay drive by cable throttle body.

http://downivlife.com/pics/1961Impala/LS3intake.jpg


Installed.
http://downivlife.com/pics/1961Impala/enginetop.jpg

Wow, you actually started a build thread here! And at 3am no less.......:D

It's all your fault! Hahaha!

Apparently I can't stay up that late, I fell asleep while typing... Hahaha I hope the earlier bit makes sense.

After the assembly and a few test fits, I get the engine and transmission installed in the car after a combination of notching the front cross member, custom engine mounts and a custom transmission cross member.

http://downivlife.com/pics/1961Impal...ialtestfit.jpg


In this photo it’s a bit difficulty to see but the oil pan hangs about 1.5” below the crossmember. No good for something that sits low or will be driven a lot.

http://downivlife.com/pics/1961Impala/musclecarpan.jpg


My home brew custom adapter plates.

http://downivlife.com/pics/1961Impala/adapter.jpg


For additional space concerns and a leak proof seal I also added fleabay V-band clamps to my Sanderson short headers.

http://downivlife.com/pics/1961Impala/header2.jpg

http://downivlife.com/pics/1961Impala/header3.jpg
http://downivlife.com/pics/1961Impala/header4.jpg

http://downivlife.com/pics/1961Impala/header5.jpg

http://downivlife.com/pics/1961Impala/header6.jpg

LS3 intake bottom

http://downivlife.com/pics/1961Impala/intakebottom.jpg

Glad I could help! :angel:

Love these old cars especially with LS swaps. Gonna have to follow along...

I'm glad you like it aggie91. Rest assured, there is more to come. :)

I’ve used a variety of methods for supplying fuel to these engines and this time I used what I had lying about – some left over OEM style nylon 3/8” fuel line from a previous project. Long ago I built a tool to install the factory ends in the nylon line and ran the length from the tank to the engine securing it with 3/8” rubber isolated clips. The only real down side to this line is bends and potential exhaust heat. Any directional changes need to be mellow or broad and sweeping as the nylon fuel line doesn’t tolerate sharp turns without kinking. In the future I’ll run NiCopp metal fuel line but I needed to be quick and metal line is easier to work with the body off which will happen when I replace the full floor.

http://downivlife.com/pics/1997tbird...ne/image01.jpg

http://downivlife.com/pics/1997tbird...ne/image02.jpg

http://downivlife.com/pics/1997tbird...ne/image08.jpg


I ordered a retrofit EFI tank from Tanks, Inc. The stamping is made overseas, but is a good copy of the original and modified for an in tank pump, adjustable sender and internal baffle. I have two complaints with this setup. My first gripe is with the fuel pump fittings location, and the second is the gasket material they sent.

The first problem is where the vent and return wind up which is just in line with the tank strap on the passenger side. My initial installation and test fit was setup in the most logical method with the fittings directed forward as the pictures below will show. Since I used the box the tank was delivered in as a stand to do my installation, I didn’t realize the grove was actually for the tank strap until mounting it in the car. This is easily rectified by clocking the fittings, however in my opinion this is annoying and should be fixed on future production runs. Simply moving the sender and pump holes two inches toward the center would make all the difference.

http://downivlife.com/pics/1961Impala/fuelfittings.jpg


The second gripe I have with this product and far more important than the first is the gasket material delivered with the tank. I’m not sure what type of rubber the supplied gaskets are made of but when I picked it up it didn’t feel proper for long term fuel handling and I was right. I only had a few tanks of fuel through the system and none were even partial E85 like I plan in the future before the gaskets started leaking. My entire fuel system is E85 compatible except these two gaskets, which apparently aren’t even E10 (normal local pump gas) compatible. I discover this right before the first show in which I fill the tank for the first time and see gas dripping from under the car. Awesome. I have since pulled the gaskets and used Permatex Motoseal on the gasket surfaces. The Permatex has been working well for over a year.

The spots are actually rust dust from the chassis when I removed the tank from the body.
http://downivlife.com/pics/1961Impala/gasket1.jpg


The supplied gasket after two or three tanks of E10 fuel.
http://downivlife.com/pics/1961Impala/Gasket.jpg


Sealer I used as a replacement for the fuel pump and sender.
http://downivlife.com/pics/1961Impal...exMotoseal.jpg



The good things about the tank are it is a 100% drop in solution and if ordered properly comes with everything you need but gas and a car to bolt it to. The pump kits you can order tanks are supplied with real Walbro internal pumps. These are the only brand I will use and completely reliable. I ordered the GPA-6 pump because of my future E85 and engine mods. The baffle is very simple, but works well down to the last gallon or so and the tank is quite affordable. I would purchase this product again and recommend it to anyone looking for a drop in solution for a 1958 to 1964 Impala (non wagon) chassis.

Inside the tank showing the baffle.
http://downivlife.com/pics/1961Impala/filler.jpg

http://downivlife.com/pics/1961Impala/sender.jpg

I purchased a GM fuel composition (flex fuel) sensor # 13577429 and pigtail and wired it into the PCM. With a bit of programming the PCM now knows the ethanol content of the fuel at all times and calculates the proper air fuel ratio accordingly.

http://downivlife.com/pics/1961Impala/flexsensor.jpg


I used HP Tuners to tweak the air fuel ratio with 0% ethanol (far left) to 100% ethanol (far right) and spark tables.

http://downivlife.com/pics/1961Impal...alibration.jpg

http://downivlife.com/pics/1961Impal...sparkadder.jpg



Transmission lines are hand bent NiCopp and flared with my Mastercool 71475 hydraulic flaring tool to fit the clip in 4L60E fittings. This tool also does the quick disconnect GM fuel lines, double flares and several others. I sourced a plate and fin transmission cooler from the salvage yard that fit the space so I made it work.

http://downivlife.com/pics/1961Impala/cooler.jpg


This is an example of two popular flares I can make with my hydraulic flare tool. On the left is a GM quick release transmission flare and on the right is a GM quick release high pressure fuel injection line flare. Not cheap but well worth the money.

http://downivlife.com/pics/1961Impal...issionfuel.jpg


One of these days (I keep saying this) I’m going to build a folding engine test / storage stand on wheels. Maybe this coming summer… I stripped the harness just enough to fire and run the engine, I wasn’t trying to win any best harness awards. At this point I’m only looking at mechanical issues, any codes, electrical or calibration issues like the intentionally slightly high idle seen in the video below will be addressed later.

Test start:

Stripping the truck harness and getting the layout like I want it.
Stock untouched harness.

http://downivlife.com/pics/1961Impala/harness.jpg

http://downivlife.com/pics/1961Impala/harnessbefore.jpg


Stripped harness in process to see how it naturally lays out. Not well.

http://downivlife.com/pics/1961Impala/drapedwiring.jpg

http://downivlife.com/pics/1961Impala/drapedwiring1.jpg


Nothing has been extended at this point, just laid how I want it to flow.

http://downivlife.com/pics/1961Impala/harnesspath.jpg


Most wires extended.

http://downivlife.com/pics/1961Impal...immedroute.jpg


Trimmed down and organized a bit.

http://downivlife.com/pics/1961Impal...eextension.jpg


Finished result.

http://downivlife.com/pics/1961Impala/wiring.jpg

http://downivlife.com/pics/1961Impala/wiring1.jpg

http://downivlife.com/pics/1961Impala/wiring2.jpg


With the engine wiring 90% complete, it was time for another test fire to ensure everything was working as desired. This time I was able to start the car with the key and run it for several minutes. The electric fan is hooked up and programmed, the relays are all in place and everything works as desired.

What temps do you set for your fans to come on and go off? Running 1 or 2 e-fans?

I'm using a 16" Derale single mounted on a sheet metal shroud. The PCM is set to turn the fan on at 185° and off at 179° with a 160 degree thermostat. My high temps in heavy cruising / stop and go traffic on a 90+ degree day are around 188°.

This image shows an additional angle on the Sanderson generic LSx shorty headers with high temp sealer on the flange. In a previous post I showed a picture of the v-bands I later added to each header.

http://downivlife.com/pics/1961Impala/header.jpg


My original upper radiator "hose" was going to be this little custom baby. That is until I discovered my original radiator had an irreparable leak. I changed to an aluminum dual pass cross flow radiator. Oh well, more welding practice and wall art.

http://downivlife.com/pics/1961Impala/custompipe.jpg

http://downivlife.com/pics/1961Impala/custompipe1.jpg

http://downivlife.com/pics/1961Impala/custompipe2.jpg


This image shows the bottom of the master cylinder I replaced 20 years ago. It had a mystery leak and wouldn’t build pressure when trying to bleed the brakes. The internal seals were bad and it leaked through the push rod hole inside the firewall. To be safe I replaced all the hydraulic components of the brake system except the steel lines.

http://downivlife.com/pics/1961Impal...ercylinder.jpg


I made my own exhaust from mandrel bent tubing. This was early, before I decided to switch to v-bands. If you haven’t used them, v-bands are awesome for a reason.

http://downivlife.com/pics/1961Impala/exhaust.jpg


CBM billet water neck. This is a very nice piece. It’s actually designed for the Gen IV water pump I will switch to in the future.

http://downivlife.com/pics/1961Impala/waterneck.jpg

http://downivlife.com/pics/1961Impala/waterneck1.jpg


Here I’m power washing 50 years of ick and random paint from the trunk. How often do you get to power wash the interior of a car?

http://downivlife.com/pics/1961Impala/trunkwash.jpg

Yeah, that's fun! I pressure washed the whole inside of my wagon, should have taken pics, after I tried spraying off all that crap (asbestos???) they put on the inside of the roof, it looked like someone blew their brains out in it, made a mess of the dash and windshield......:barf:

My roof insulation is still in one piece. Hopefully it will come out that way.



Custom engine mounts I made for a friend of mine and his 1963 Impala wagon swap. Mine are a similar design, but the only pictures I had were from his build.

Rough mockup with engine level and held in position by a jack or other steady means.

http://downivlife.com/pics/1961Impal...passmount3.jpg

http://downivlife.com/pics/1961Impal...passmount4.jpg



Cardboard template pattern used to make the next piece. Due to mimicking the factory design, none of these pieces can be the same.

http://downivlife.com/pics/1961Impal...passmount5.jpg

http://downivlife.com/pics/1961Impal...passmount6.jpg



Quick tack weld before test fitting again.

http://downivlife.com/pics/1961Impal...passmount7.jpg



Finished product.

http://downivlife.com/pics/1961Impal.../passmount.jpg

http://downivlife.com/pics/1961Impal...passmount1.jpg

http://downivlife.com/pics/1961Impal...passmount2.jpg

To go with the custom engine mounts I needed a custom transmission mount. I know I have progress pictures of the thing but the only one I can find is after I installed it.

http://downivlife.com/pics/1961Impal...rossmember.jpg


Trailing arms seem to be very expensive for how basic they are and I’ve never understood why. There are several companies selling only lower trailing arms for $200 and up. Fine for all the bolt-in guys out there, but I’m not in that crowd. I try to save money on things I can build so I can spend it on things I can’t. As you will see, trailing arms are one of those things I can build. Hopefully after this you can too.

I started with a bunch of dead bushings like this one…

http://downivlife.com/pics/1961Impala/deadbushing.jpg


This is the result of spending $20 or $25 from my local cut metal supplier, even less per unit if I need full lengths.

http://downivlife.com/pics/1961Impala/trailingarms3.jpg


Simple jig from scrap material.

http://downivlife.com/pics/1961Impala/jig.jpg


Bushings mocked up in outer sleeves I made from the shorter piece of tubing.

http://downivlife.com/pics/1961Impala/jig1.jpg


Using washers as temporary spacers and set the level at 0.0 in relation to the jig.

http://downivlife.com/pics/1961Impala/jig2.jpg


Close up of the handmade notch before welding.

http://downivlife.com/pics/1961Impala/jig3.jpg

http://downivlife.com/pics/1961Impala/jig4.jpg

http://downivlife.com/pics/1961Impala/trailingarms.jpg

http://downivlife.com/pics/1961Impala/reartarms.jpg

http://downivlife.com/pics/1961Impala/reartarms1.jpg


New rear springs.

http://downivlife.com/pics/1961Impala/rspring.jpg


Dead shocks with new shocks.

http://downivlife.com/pics/1961Impala/shocks.jpg


Installed with new springs and shocks.

http://downivlife.com/pics/1961Impal...sinstalled.jpg

Subscribed! I love it!

Thanks man!

Like what your doing, wish I were closer to you KC guys, I could learn a lot.