1970 LeMans Repower
 

Working on making a build thread on this project. Been a many year deal. Was my dads high school car. And when I inherited it from it was still riding on tires that were installed before I was born. Started out life like this.

Good luck on your project. Having been your Dad's car makes this extra special.

Dad had the car sent back to his friend in Alabama who restores Pontiacs for a hobby. Paid the guy piecemeal to get it back in shape. Looks pretty good. Dad and I went down and brought the car back home. After that it sat at his house for about 8 years and he did not do much of anything with it. This is how it looked when we got it back home.

In 2012 my Dad called and asked a really goofy question. He asked me if I would trade my rarely used Polaris 500 sportsman for his LeMans. Well of course I'll take that trade. So I took it home and got to work getting it back in shape. Installed 4 wheel disks. Changed the iron intake to a performer RPM. Added a new carb. Changed the distributor over to HEI. Added an MSD Digital 6AL. New wires etc. Also car was still running the factory shocks. So changed those as well. After that added the hood tach and new head lights. Makes a big difference in driving at night. The car still had 2 of 4 OEM T3 headlights. Swapped over to HID lights and and Halogen low beams. Was a big difference. When swapping the brakes over found out that the rear calipers would not clear the factory 14" rally wheels. Had to get some steel 15" wheels for the time being. Started driving the car and enjoying it.

Yup it has been fun. Getting to the end though. Well they are never really done but 2020 was the year I wanted to really get after it. So now that I got pretty far and am just working on finishing some small things figured I'd post about it. Not the kind of guy that tells a story much. But have been reading and learning from the great guys here.

Silver w black top looks fantastic! Very nice ride. Was the brighter light as simple as swapping headlights or was there a wiring change?

Swapping the lights was just changing over to non sealed beam glass and then adding the HID kit. The glass I got has the reflector to cut down on the glare to other drivers. The HID kit was pug and play. And I have them wired as the highs and it does not bother traffic coming at me. (well I never get high beamed)

Drove the car off and on during the summer on the weekends. Started to plan other upgrades to the car. First on the list was the suspension. Seeing that the stock shocks were on the car and that the other bushings were cracked and worn. I placed an order with UMI Performance and installed their full stage 3 kit and installed it on the car. Unfortunately I cant find the pictures of that or of the new Dakota Digital dash install. Car handles so much nicer with the new suspension on. Made a world of difference. I recommend UMI and their products.

The Dakota dash really made the car nice to drive and gauges easier to read and kind of solidified the Pro Touring or RetoMod theme. I like the old car look but wanted some of the modern touches. This car was never numbers matching and it sure is not a GTO or collectible in that sense. I do find it cool that of the car shows I have been to, I never see another Lemans though.

Also while under the car doing the new suspension I took out the stock carrier and gears and installed a set of 3.73 gears and a posi-traction unit. Installed new bearings and seals and installed a rear cover and bearing cap braces. I am pretty sure based on tooth count that the stock ratio was close to 2.73. I know that it would hardly get moving but once it was going it cruised really well.

All of this work was completed in 2014-2015. I also installed a new Kenwood head unit and new pioneer rear deck and kick panel speakers. My uncle had already butchered the dash metal to install a Sparkomatic some "wally world" brand I guess radio. It was around this time I began contemplating the next steps for this car. The original 350 still ran excellent but time had taken its toll on all the gaskets. They were all starting to leak and the motor was due for a refresh. Story from my father was that it was rebuilt in 1980 and was from one of his earlier cars. I cant remember if it was a GT-37 or another car he had. The trans was a TH400 with a TransGo shift kit in it as well. So by this time the motor and trans had about 35 years on them.

So it was a difficult choice for me on what to install in the car. I really wanted to stay with pure Pontiac power. But after doing the research and making various budget sheets and pro/con lists, I settled on going LS. I just at this point in my life could not justify the dollar per HP ratio. Where I work almost 98% of our fleet is LS powered and I get first dibs on any retired vehicles. Also I already had a fully rebuilt 5.3 that was siting on a stand in the garage.

So in 2016 I started gathering parts together for the swap. I wanted to have it all ready so that I could enjoy the car while I was working on getting things together. I finally had every thing together this year. And I really got started in November and took the car off the road. Before that I had the car ran on the dyno to see where it was before I got started.

297 Tq
228 WHP

Goal would be 600- 700 WHP

I do like the Dakota gauges . The headlights too, help add the updated look to a classic car. You've made yourself a classy ride!

Thanks working on it. Hope that it all comes together. I have a lot more updates left to post.

So earlier this year I started with installing new Year One rally wheels and firehawk rubber. 275/40/17 on all 4 corners. Really changed the look of the car. Also I added a new steering wheel as the current column is not tilt and the original steering wheel was turning to Goop. Started gathering parts for the swap and planning what I thought I could have done before spring 2021.

Got the new steering wheel installed. Also took this time to invest in something I've never owned and got myself a lift for the garage. Always done my work on ramps or stands. Not anymore. Sure it's not a 2 post but I don't have room for that in my current garage. 15x32x8'. So got a Quick Jack 7000# lift. It works real nice and fits all of my vehicles and its fairly portable. My son finds it awesome that you can lift a car with a push of a button. :) Also do not have any pictures of the install but I had replaced the stock tank years ago. The sender unit was bad and once you hit 1/4 tank it quit moving. Left me stranded once. So new tanks tank and straps. Made sure I got the version with the EFI sump even back then.

Got more parts showing up. Got the oil pan in and installed. Got the LS swap kit from BRP hotrods. Found a 4L80E from our fleet. Unboxed the wiring harness that I had from the original donor vehicle for the 5.3 and got started on stripping down the harness and making it stand alone ready for the trans and for the motor. Using a cable throttle body. And started cleaning out spaces in the garage and worked on insulating the walls and recovering in plywood. Have had Heating and Cooling in the garage but was not cost effective to leave on.

Started in on the wiring harness. Fun for exercising my brain but a lot of tedious work. But got it all lined out and labeled. Dropped the rear o2 sensors. Kept the knock sensors and transmission control wires. Dumped any other non needed circuits. Laid it out on the motor and made sure everything was where I wanted it.

Was able to get a 4L80E from one of the fleet vehicles. Would not move in any gear. Started tearing it down. Got it pulled apart and found the forward clutches toasted. Cleaned the case and set it aside for the time being.

Got the new motor painted and sealed up. Painted the valve covers and the coil brackets. Painted the water pump. Ordered new alternator, power steering pump and tensioner. Installed new plugs and sensors. Also swap headers showed up. Speed Engineering stainless headers. Looks like they will fit. Took the car to a Drive In we have in town and watched a double feature. Was a classic car cruise in as well.

Took a break from the engine and transmission work. Started on the audio upgrades on the car. So built an amp rack and trunk panel. Installed sub enclosure behind the panel and then installed the panel. Installed 2 Alpine amps and power cap. One amp is for the four speakers and the other is feeding the subs. First try at building any thing like this. Have had audio systems before but they were always thrown together and not near as neat. I'm sure someone will find issues with what I did. But hey got to learn somehow. Also received oil cooler and fuel system parts in the mail as well. Going to run an in tank pump and firewall mounted regulator with return line. Also started to figure up the cost to tune and reuse the factory ECM. Holley's new Terminator X Max looks like it my be the ticket.

One of the installers at work crashed one of the vans last year and I was able to pay the buy back from the insurance to keep the van. Was really just after the engine and trans. Maybe the harness and computer as well as the hydraboost unit. Van was towed to local shop that does the work I don't want to do. The owner there called me when he ran the vin# and found that we had just replaced the transmission 15k miles ago with a brand new gm unit. Still had warranty left. So I decided to not worry about the trans I was rebuilding. Also got a Holley Terminator X Max. Found it was cheaper without the handheld and got it that way. I was always planning on using a laptop anyway for tuning.

Also picked and installed a keyless entry and start system. So no more keeping up with keys. Walk up door unlocks, sit down push brake and push button car starts. Just like a new car :). Got a new camshaft for the engine and a matching converter for the trans. So getting some parts together to really start moving now.

Sorry if I did not make it clear. I have completed the swap at this point in time. Just playing catch up on the build thread. I wish I was fast enough to get it all done this quick. I started most of the actual swap in November 2020.

cool...

Pulled the heads. Installed new lifters and trays. Installed new matched springs for the cam. Installed new head bolts and gaskets. Put motor back together. Installed the remote oil filter and fittings for test purposes. Pre lubed the oil system with break in oil. Wired up the Holley on the bench and fired the motor off. Made sure it was firing on all cylinders. All is good and nothing exited the block. Took a trip down to Somerset Ky for the summers night cruise. That was a nice time. Never been down there for that before.

Finally got started on the swap. Pulled all the connections. Pulled the hood. Got the lift setup and got the old motor out. Not an easy task to do by yourself. Got the old motor set down on the floor and secured. Got things prepped to start cleaning the engine bay. Radiator showed up at the office was worried about its condition after looking at the box. Plus its the 3rd package that FedEx has said I signed for and left but every time I have been an hour away.

Got the car rolled out of the garage and into the driveway. Washed it all down. Then sprayed it down good with degreaser. Let it sit and the pressure washed it off. I did this probably 4 times. Looks a lot better. Kept going till I could not see anything else coming off the frame. Washed the motor down as well. Lubed the cylinder bores and sealed the engine up. Then the fun part was getting the car back in the shop by my self. Luckily I had a 12 volt winch. Was able to attach that to the garage and use it to pull the car back in.

Was talking to dad, he was thinking the motor might have been from a buddies formula FB. Any way to tell from the casting numbers? It did run good. Got the car frame de greased and wiped down. Painted the engine bay. Installed the motor mounts. And started to get the new motor ready to drop in.

Got the motor set in place. And Like I knew would happen eventually ran into my first issue. The swap pan I had picked up fit in the bay. But the drop in the pan was laying on the backside of the crossmember. So I could not tilt the motor back any at all. Looked good but was not going to work. So I had to order the pan that BRP sells for this swap. Got it in and replaced and it fit perfectly. Now I will have to re figure how I am running the oil cooler lines because the new Moroso pan does not have the AN fittings that the other pan had. But at least it is in. I got pretty into finishing it up at this point so I did not take many pictures at this point. But got the 4L80E installed. No tunnel mods. Crossmembers in. Got the cooler lines made up and installed. Shift linkage installed and the factory floor shifter converted to the OD pattern. Headers dropped in. Passenger was no problem the drivers side barley kissed the crossmember. Fixed that issue. Ran the fuel lines. Installed the pump in the tank. Installed the filter on the frame. Ran my new battery cable to the front. Installed fuel pump electrics. started on the wiring harness. Measured for new driveshaft and took the old one to get cut down. About 1.75" place downtown does nice work. They called and said the old one was like a bent noodle. So it was time for a new one. Got that installed and all buttoned up.

Got the new radiator installed. Made up AN fittings for the power steering lines. Found out that the new pump does not come with flow valve. Ordered new flow valve and installed. Had to find hoses for the radiator. Found the hoses and got them installed. Filled the motor with antifreeze. Plumbed the fuel to the rail. Installed the ECU. Ordered and installed a new lokar throttle cable. Installed trans dipstick. Filled the motor and the trans. Filled the tank with fuel. Did the initial setup on the terminator. Checked for leaks and started the motor in the car first time. Open headers :) was nice and loud. Had to add temporary extensions to the headers to get the Wideband to read right. And was able to finally back the car out under its own power. Which is always a good feeling.

Built the relay and fuse panel. Relays are for low and high speed fan and for the fan on the trans cooler. Had to wire and terminate the relay panel. All outputs are fused separately. Signal wires go to the terminator to control the fans based on coolant temp and trans fluid temps. Got the cooling fan mounted. Using a windstar fan. 2 speed fan with the shroud. It actually fits well. Keeps the engine temps at idle in check perfectly on only low speed. I will know better once I can get out this spring and drive it. Fans good deal on rock auto less than a $100.00

I can't read the 2 letter code on the block below the cylinder head...that would help identify what car the engine came out of. The head casting # appears to be 16...if correct, off of a 400. There's also a date code stamped into the block near the distributor(left side looking from the rear of the block). The casting # on the rear of the block(9790079?) 68 or 69 350.

I cant get a better pic of the 2 letter code. Don't have access to the engine right now. Been out of town visiting family.

Before xmas got my new Pypes exhaust system in. Its the 70-72 with valance exit and cut outs with the x pipe. Also got the race pro mufflers. Ordered their 2.5" split tips as well. Got that all installed along with a set of electric cut outs. Sounds really good.

Only issue I had were the clamps. kit came with regular exhaust clamps. And I got ten of them. Well there are more than 10 joints that require clamps. So I just ordered the correct number of band clamps and installed them. The fit is great. All I need to do is adjust the tailpipes a little I want the tips up in the valance cut outs.

Also got the battery mount finished and bolted in. Need to finish installing proper cables and mounting breaker and fuses. Decided to change the front grille insert color. And installed the new cold air intake tube and filter. Worked on the cold start and idle tuning. Started working on installing a transmission line pressure transducer. Started to clean up the wiring under the hood and need to get car on a big lift and finish cleaning up the fuel lines and wiring under the car. And then get the range selector hooked up to the reverse lights as well. Also got all the other bulbs in the car swapped over to super bright LED bulbs and electronic flasher.

Is your exhaust 2.5" from headers to tails? If so it's going to choke your horsepower goal

Yes I do not disagree that is probably going to be the case. My goal will not be on all motor. Already looking for a new LSA blower for this fall or winter 2021 install. So I will see what can be made on this system. My issue was if I went 3" I did not see a system that guaranteed valence exit. And all the local shops cant do mandrel and would not do stainless. So I would wonder what the difference would be on open dumps? I know that the hellcats run 2.75" pipes. And if I cant get there on 2.5" then I will look at other options. And I might decide that 500ish is enough for me. I could I guess always change it to 3" up to the dumps then leave the rest but I guess we will see. Highest WHP car that I have ever owned/built was 398whp 325tq turbo 4 cylinder. So If this gets north of that maybe Ill be happy.............................. Probably not :) Maybe that's why I've owned 32 cars in 20 years of driving :)

Size comparison from what was on the car when I got it to the new pipes system. Old exhaust was what the 350 was dyno'd on.

Changed the headlights out on the car. Found some with better projection characteristics than what I had on there. Plus they have turns built in as well. Seem to work better and they have a way better light cut off. Changed the oil and filter again. Ran it through a couple heat cycles. Going to start going over connections and clean up more wiring. Probably going to order my vintage air next and work on getting that installed. Nothing but ice and snow here. So no real test drives yet. Hopefully we can get her out in a month or so. May have to fix the ramp into the garage cause the new exhaust might hit. Need to maybe extend it out. That way its less steep.

Enjoyed reading your thread, lots of cool updated goodies.

Thanks. Just trying to make her the way I would like. Want it to be my nice weather driver. Have a company vehicle and good car for my wife. But I want to have something different to drive around and enjoy.

Got a few more updates going on. Found an idea on the center console from another forum. So going to give that a try and see how it turns out. Picked up some carbon from Rock West to make the top plate. Ordered a shift indicator from Lokar. Also got the shifter module from Dakota. It will integrate with the VHX gauges and the Lokar indicator. Plus will give me an output for the backup lights as well. Picked up a wireless charging pad for my Iphone and am going to graft that into the front pocket in the center console. Can't decide if I want the gloss or the dull side up on the center console. Also looks like I am going to be able to order the Vintage Air, rockers and hardened push rods this month as well. Hope I can get that all in before summer. Finished extending the ramp from the garage yesterday. Still not sure on the exhaust clearance from the ground. Edges of the cut outs are 2" lower than the trans pan. Just looks low to me. I have the x pipe touching the drive shaft at full droop. When under compression at ride height its about 2" above the x pipe.

Have more things going on with the car. Got a bunch more parts showing up. Going to be a fun summer. :) LSA blower showed up. The new front drive showed up. Started getting the new center console installed. Got the supercharger lid. And continued working on the shifter plate.

More stuff done
 

Got a few more things done. Got it up and running. A few more things to work on. HVAC controls came in. Vintage air will be here tomorrow. Will have to get that installed. Working on tuning. Then a trip to the dyno at some point. But running real strong at this point. :3gears:


https://youtu.be/UilwHFq6YSA

Well have had a lot of things that have been goin on. But have made progress on the car. Did finally make it to the dyno. Made a few pulls and got some good numbers. Developed a lifter noise. Tore it down found collapsed lifter. Installed new johnson Tie bar lifters and new push rods. Added head studs and a ported inlet for the LSA charger. Smaller pulley on new snout. Have not been to dyno since the upgrades. On the dyno was running only 12 degrees of WOT timing on pump. Making about 6 pounds of boost. If I can get the uploads figured out I will post more pics. But every time I try I am getting errors. The Dyno was WOT at 3200 and ran out to 6000. Torque was 400+ from 3700-5800 WHP was over 440 and had not peaked at 6000.

Just found your thread, enjoyed seeing all the work you have accomplished. Very impressive! Beautiful car and so much for you to feel good about.

Do you happen to know if the rear valence is steel or aftermarket? Did your dad make that change when he had it painted? Good to hear the exhaust system fit well... lots of conflicting info on that one.

Does a 4L80E fit under the tunnel without having to cut or hammer sheet metal?

The Valance is steel. It has been on for over 20 years. Dad had it changed out and I am not sure where he got it from. Yes the 4L80 fit with no tunnel mods and I used the Factory shifter and cable. Just added the shiftworks conversion kit.

Thanks!

Yup if you have any questions just feel free to ask. As soon as I can get pics to load I will update the thread again.

New baby came yesterday :-) Maybe I will have some time to fix this photo issue this week while I am home getting everyone back on track.

Congrats!

http://Way2qwk4u.quickconnect.to/mo/sharing/g9bGW0F6P


Lets see if this works.

Attachment 596780

Got the photos figured out I believe. Now I got to go through and fix all of them again. But here is a shot of the new snout. Hope this pic comes out ok.

Link to pics worked fine for me, thanks.

That's way above my head but those are fancy-looking parts!

Thanks. It took me years to get things together and about 2 months to get it put together.