1981 Pontiac Trans Am LS1 Swap - South Africa

[Picard]

I test fitted the dash. Need to still hook up all the wiring. So far everything is sorted. Got the two harnesses working together. The car starts and idles and lights etc all work. The only issue we’ve picked up is the indicators seem to indicate slower with the headlights on than with them off. We’ll figure this out though.


I have a hole in my bonnet    Need to make up some contraption here still to hold the shaker hood. Lots of guys end up welding it to the bonnet, but I’d like to make it as it was intended.


This is how she’s looking at the moment.


Planning to bleed the brakes this weekend and get her out the garage so that we can run the motor up to operating temperature and make sure the fans all kick in when necessary and see what errors we pick up. Fluids have all been topped up.  At the same time, a quick wash to get all the dust off. I feel sorry for the neighbours as that V8 with only headers is extremely loud, but sooooo nice  :drool:

[Picard]

Been a bit slack getting to the workshop. After getting the Trans Am fired up I noticed a bit of anti freeze on the garage floor. As luck would have it a dam seal on the radiator must have let go, so I had to get it all out and sent in to Silverton. It was a bit of a mission as the transmission cooler, aircon radiator and fan shroud are all connected up to it. So to get it out and split apart was a real pain in the butt. Not really a great pic but got back the radiator all painted black, instead of the aluminium colour it was before.


Decided to sort out the T Tops. Stripped the original seals off and they've been replaced. At the same time, I mixed up some paint I had from Barry, sanded and primed the tops and painted them up nicely.


My brother's pretty good at painting, so got him to do it. Came out quite nicely.




I've been busy with wiring...lots of wiring.


Having gone with the Lumina motor, unfortunately I've had to lose the original instrument cluster. I've replaced all the gauges with Speedhut rev counter and speedometer. I've reused some of my VDO gauges that I had with the 383 and also added a VDO fuel gauge.


I can't wait to test out the Speedhut Speedometer as it's a GPS based unit.

The fuel gauge was quite easy to hook up. Connected straight up to the original sending cable.


Hooking up the water temp sender wasn't too difficult. I had a spare spot on the side of the head I was able to use. For the oil pressure sender, I followed a guide found on the web, where you need to drill and tap into a cover located by the oil filter on the LS1's.


This is how it looks now with a VDO oil pressure sender sticking out of it.




This is a friend's car. Went for a drive in it and was impressed as to how quick it is and the whole feel. Very different to a big V8 and def not made for someone of my....um...size.


Kitt's got nothing on this.    It's only a reflector.


Managed to get the TA out the garage and blew most of the dust off, and at the same time a quick wash.


And finally...after a few years and lots of work, I got to take my Trans Am for a quick burn up and down the road.

I was pretty nervous as there's still quite a bit of testing that needs to be done to make sure everything's bolted on properly etc, but the anticipation was killing me. We fired the TA up, engaged Drive....made sure the brakes were working and off she went.

[Picard]

A quick update on the Trans Am build.

The front and rear glass has been installed and the window trim all fitted.




The dash is in and my gauges are hooked up and working. I'm very happy with the Speedhut gauges. They came out looking good and were a breeze to install. The Speedometer is a GPS unit which you litterally hook up 12v to and you're on your way.  The Rev counter is really very Fast and Furious like...with a built in shift light and a couple of extra features......but it's grown on me.

I need to put in a diode or change the indicators on the dash panel as they are extremely bright.




Next up on the build was my final big expense, the exhaust system. I called around to some of the more well known places and was getting quotes around the 10k to 15k mark    for a set of pipes to the back. This was excluding manifolds/branches. I ended up going through to a SupaQuick I was referred to.

I had the car flatbed through as I did not want to drive it to far with just the manifolds on.


I opted for 63mm stainless steel system with Cowley free flow boxes. I checked the grade of the material used and it was in order.

I spent a whole day with the guys mocking it up and explaining how I wanted it made up. They've built it in a way that if I ever need to remove the system, it splits into 3 sections.




I had them weld in the bungs for the 02 sensors so that I could keep the originals.


This is what the two boxes look like.


I don't like seeing the exhaust pipes sticking out of the back of a Trans Am. When I bought my Trans Am it looked like a wheel barrow. I had them bring them down at an angle and cut them so they remain hidden.


Unless you look under the car, you won't see them.


It came out sounding better than I expected. There's no drone and it has a very deep typically American V8 rumble, which I like.

I've still got lots of odds and ends to do. I've put together a list of things that need to be finished and am working my way through it all.

Now it's nice work though. The sort of work that lets you tinker on the car and then go for a drive.

Took it through to grab some roadhouse lunch.


Some competition arrived while I was there 


It's still a bit to early for me to comment on the difference between the LS and my 383 Stroker. I will be able to feedback once I get some mileage into it.
So far I'm extremely happy with it. It starts immediately...idles perfectly and pulls like a train.
I've noticed that the ride feels exactly as before except that the shifts are super smooth compared to the stupid box I had in before with the shift kit.
The brakes are not even comparable. The conversion to discs on the back with the bigger discs up front with new calipers have transformed the braking system completely.
It stops now....something it never did before.
I managed to get her up to about 100KPH and she literally idles over at about 1400rpm in overdrive.
The cooling system works perfectly.

I think my 383 Stroker may have had a bit more bottom end torque compared to the LS motor. I used to just prod the peddle and it would light up the rear....well...one of the rear tires with the open diff.    It would run out of revs quickly though and the old cast iron heads could never give you more.

With the LS I can feel that difference in bottom end torque....but my god...as soon as those revs pick up this Trans Am comes alive!
I've only given it the beans once or twice and so far I am seriously impressed.

[Picard]

Thought I would do a quick catch-up on my post on this forum for those that were following it.

I have had quite an entertaining time with the Trans Am over the last few months. I’m put on about 3000km’s and some of them happy miles with smiles and some really frustrating niggles.

I fitted the under hood blanket


Then I had some fun times trying to make the shaker fit. Many people end up welding it up to the bonnet, but I decided I wanted it to shake. Although the LS is smooth, it is nice to see it moving around.






I started taking the car out on longer trips and making up my snag list of issues that were bugging me.

[Picard]

First up was a drivetrain vibration. I kept experiencing a vibration on acceleration and while cruising.
I landed up taking the wheels to Monte Carlo wheels in Edenvale and had them make up some spigot rings. This exercise was extremely frustrating as the level of workmanship is quite scary. Anyhow, after two attempts, we managed to get it sorted and it the vibration issue improved slightly.




I still was not happy with it though and landed up back at Propmaster in Edenvale. I had them make up the prop during the build using the Lumina’s original prop. After hoisting the car up on the lift and running it in the air, we picked up what was happening. Something simple….yet enough to give me so much grief. The Lumina has a rubber piece (Think it’s called a Guibo) and it was just slightly rubbing up against the underside of the car. I had never spotted this.

When I fitted it, it seemed to clear with no issues. A new prop was made up, using an Isuzu bit and all vibrations are gone.

Second up was the rear suspension. I was not happy with how the car with sitting and riding. It felt as if the rear had sagged and it was extremely low. It would scrape the exhausts over every bump.
I landed taking it through to Golden Spring in Selby. They removed the leaf springs and made up a new set. I also messed around with the rebound rate on the Koni's. What a difference! The car rides nicely now. You can actually carry people in the back and it handles the bumps nicely. It may sit a bit higher than I like, but it is more practical with the quality of our roads.

[Picard]

The big balls up I’ve had though, which has really put a damper on things has been the gearbox.

So, I originally sourced a 4l60e from Porky from American Motorsports. I purchased it from him knowing it had been refurbished and according to him beefed up to handle more power.

He agreed that he would honour the warranty on the box from when I got the Trans Am up and running.
In the mean time, I purchased the Lumina and stripped out it’s motor and gearbox. I decided it would be best to sell off it’s gearbox and use the gearbox purchased from Porky as it was “new”.

We fitted it and since day one I had a bit of a bad feeling about it. I picked up that when punching it, it would bounce off the limiter in first before shifting into second. I figured this was maybe something to do with the shiftpoints, but Izak set everything up and it was still doing it.
The other thing I noticed was that when cruising it would hunt around ever so slightly….almost as if it was battling to get into or stay in overdrive.

Somewhere in November, I was having a friendly race against my brother in his M3 when it bounced off the limiter in first to second....and then at the top of second it also didn’t change. I immediately backed off and it carried on as per normal. That evening I took it out again and this time it went into limp mode.

I called Porky….leaving messages for him for 3 days with the promise that he would call me back. On the 4th day I managed to catch him when he answered the phone. I could tell straight away he was not too interested in helping me out to resolve the issue. Immediately he became defensive with shifting the blame onto how I installed the box, wiring etc… He suggested I get the car to him where when he had a chance to put it into his workshop to work on, he could investigate. He confirmed he would get back to me with when I could send him the car, so that it doesn’t sit out in his yard.

Well, not surprisingly, until today I have not heard back from him. I decided to not waste any energy with American Motorsport and sort out the issue myself. The thought of the drama of leaving my car with them and then the frustration in trying to have them feedback to me what was happening made the decision clear to me.

We decided to take on the task of rebuilding the 4l60e gearbox ourselves.

I removed the gearbox, which was a pain in the arse. We really need a lift at the workshop as I'm getting to old for working under cars. My unique physique doesn't help the case much either 



The gearbox oil smelt quite bad and once removing the pan, I was surprised to see how much gunk was in there. The pan has a magnet to attract any filings etc, which was covered in black gunk.


After a bunch of disassembly, we landed up with a table looking like this.




From what we can figure out, the gearbox suffered what is commonly known as  ¾ Clutch failure. It seems to be one of the common failure points on the 4l60e’s.
We realised something like this could be the problem when we were trying to remove the input drum. It’s supposed to come out easily, but no matter how hard we pulled on it, we couldn’t get it out. Eventually…after a good couple of hard bangs on a piece of wood on the floor it came out.

Once we got the forward clutch pistons we found this.


It seems, when this box was rebuilt, this seal may have been pinched. I’m guessing this would cause an issue with not enough line pressure, which will burn up the 3-4 clutches.

[Picard]

Quick update.

Unfortunately I didn't take many pics of the assembly, but most of it was pretty self explanatory.

The torque convertor was sent off to Fullrace and two or three days later was sorted.

It always feels like Christmas when you receive boxes from the States.  My Sonax Smartshell and new wiring harness with all the solenoids arrived safely.


I compared my original sunshell to the sonax one, and they look pretty similar. The Sonax is supposed to be much stronger, heat treated and apparently stops spline stripping, hub breakage
and also eliminates planetary bearing failure and all in all seems like a good piece of kit.



The kit came with the heavy duty reaction shell, thrust bearing as well as a custom roller clutch race


Assembling the gearbox went well. We took our time, measured up everything and started putting all the bits together together.

The input drum was built up with all the clutches and measured out.


We stripped and cleaned out the valve body. This one was quite tricky with lots of little parts.


We finished assembling it and fitted the plates with all the check balls. 7 of them if I remember correctly. Once that was done, we carefully fitted the valve body, making sure we didn't mess any of the balls around.

Everything got torqued up to the specified amounts


So this where the fun part began. We fitted the gearbox....bolted everything back together again and filled it up with oil. After a few hours on Saturday morning.....I finally got it ready to start and test.

With the rear wheels off the ground, we fired her up and ran her through the gears. Put it in reverse....nothing. Put it in 1st, 2nd, 3rd and Drive and it works perfectly. Try reverse again..... :'( Nothing.

So I start trouble shooting and eventually decided to hell with it and removed the gearbox....again.

During the build I had asked for advice from a gent who repairs gearboxes from home and I contacted him to ask him to help me check it out. He agreed and I took it through to him. I suspected it had been the reverse boost valve and he confirmed it. A dam circlip which we must have not seated correctly popped off and fell into the sump.  >

While it was with him I gave him the go ahead to do a modification to the apply servo for better engagement on the band.

The box came back and I fitted it up again. Ran through all the tests and it's working perfectly now.  :bravo_2:

Pulled the car out...gave it a nice wash and drove it home.



On the highway she ran perfectly. Came off the highway, taking it nice and easy it ran through the gears without any issue. As I was about a block away from home, I noticed the temperature building. Pulled over and after a bit of investigation....figured out the Thermostat wasn't opening.  and with the pressure it managed to blow off the bottom radiator hose.  :angry:

Pulled out the thermostat, refitted the hose and got the car home.



I've been wanting to replace the pump for safety's sake, so I did a bit of calling around to see if I could source a new pump locally without needing to order one in from the states. After a bit of help from the gents on the lumina owners whatsapp group, I managed to source an Airtex pump as well as a thermostat from the V8 Shoppe and fitted it last night. This weekend will spend some time testing it out.

One thing I will be fitting now, as a lessons learnt, is a CLD unit. (Coolant level detection). My brother supplies these units and had warned me to fit it as we normally do so on the old cars. This unit would have picked up that I had no water running through the hoses and immediately warned me about it. I was lucky enough not to damage anything.

[5th T/A]

After your original post got lost with all the others earlier this year glad you went through all the trouble to repost again. Incredible detail that will help others undertaking such an elaborate project and hopefully provide inspiration needed to keep going.

Funny how an engine upgrade turned into a complete restoration, but that’s what happens. In the long run you will be happy you went through all the hard work and expense.

I am curious as to how you mounted the shaker hood to the LS engine. Seems like that would be challenging.

Beautiful car, hope you gets lots of enjoyment!

[Maxthe222]

Better a LS over a chev 350 so that's a good decision, I'm actually surprised how many T/A's there are in South Africa? This car looks like it's a Y84 SE as well, did you find a buildsheet or PHS for that car?

[Picard]

After your original post got lost with all the others earlier this year glad you went through all the trouble to repost again. Incredible detail that will help others undertaking such an elaborate project and hopefully provide inspiration needed to keep going.

Funny how an engine upgrade turned into a complete restoration, but that’s what happens. In the long run you will be happy you went through all the hard work and expense.

I am curious as to how you mounted the shaker hood to the LS engine. Seems like that would be challenging.

Beautiful car, hope you gets lots of enjoyment!

Thanks! I will put together an updated post with how it's been and all the fun I've had with it since completing the build. Although....is it ever complete?
I just thought to transfer the post from another forum onto here.....in case i helps anyone.

I'll take a picture of how I mounted the shaker. Wasn't anything too complicated. A simple bracket I made up.

[Picard]

Better a LS over a chev 350 so that's a good decision, I'm actually surprised how many T/A's there are in South Africa? This car looks like it's a Y84 SE as well, did you find a buildsheet or PHS for that car?

I daily drove a 2004 Chev Lumina (Holden Commodore) with the LS and loved it. So, as my car was never original to start with, I was always keen to have something a little more modern and at the time.....different.
There are a few running around. I attend many of the car shows in the Johannesburg area and am always surprised how many there actually are. Nothing compared to what you find in the States....but they are around. They used to be one of the cheaper "Muscle Cars" to buy into, but not anymore these days. Unfortunately many of the ones we find here have been fiddled with.....and not in a good way. Finding a neat one is quite hard.

I unfortunately never found the build sheet. From what I can see from the VIN code...it matches up to a black 1981 Trans Am, originally with an 4.9l V8.

[Picard]

So glad to see it didn't get lost! Thanks for recovering the site.

[737driver]

Really great work on the project! Looks like it will definitely be a great car! I’m sure it gets lots of attention in SA.
Jim

[Picard]

Really great work on the project! Looks like it will definitely be a great car! I’m sure it gets lots of attention in SA.
Jim

Thanks Jim! It sure does. As you hardly ever see them here you land up driving around feeling quite special with all the attention it generates. Only thing I hate.....and it drives me mental.....is when you drive past folks and you hear them call you "Hey Michael Knight"  I've learnt to accept it 

[TATurbo]

Your car looks fabulous, Congrats!
I know what you mean about the Knight Rider comments.  For me, it's 'Smokey and the Bandit'...Now I appreciate people's memories about these cars, and I love the attention and smiles these cars bring to others. But, not every TA is a 'Bandit'.  I've actually considered a personalized plate that reads 'NOTABNDT'.

Congrats on the progress. I hope you get a bunch of enjoyment out of it!