1970 El Camino 350 Daily Driver Project - Lots of modern Modz

I am still working out a few bugs:
1. Mount electronic shifter into center console
2. Get DD gauges to register shift lever position
3. Get PCS paddle shifter display to not cut out so frequently.
4. Reverse lights not working
5. Safety neutral switch not working
6. Decide on buton combo I like - New switches on order with custon GV and O/D logos

But, more importantly I have had a few test drives now and totally love the combo of GV and paddles with electronic shifter. Everything feels great with accurate, firm shifting with predictable delays that are easy to account for.

Also, "almost" all-in on doing a rear end gear swap to Yukon 3.73s. I am still awaiting a quote from a local shop, but I am leaning towards buying a shop press and dial indicators and tackling this project myself. I plan to make setup bearings the current bearings. The big plus to the plan is that if I can handle this work, then I will do a gear swap in my wifes Jeep Wrangler. We bought it with 4" lift and 35" tires and it is a dog off the line and with top end power. We can't even get into 6th gear as it has no power at 70+ mph in 5th gear with an rpm around 1800rpm. I even added a superchips computer upgrade. It helped, but not as much as I hoped. The Jepp came with stock 3.71 (i think) gears and I plan to upgrade to 4.56 gears to restore the power, which is the recommendation I got from an avid Jeeper.

Last weekend I took the El camino down to Phoenix. It drove fantasitic! In a couple sections with lots of curves and some traffic I was able to blast through that section from 80-100mph. The suspension and control was amazing. I soooo need to get this thing out to an autocross track.

This weekend I am taking the car into the shop to replace the oil pan, oil pump, rear main seal and the front timing cover gasket. I am hoping to stop all these annoying leaks. I have been leaking more oil of late and it just drives me crazy. The driveway is a mess too. A friend told me about some driveway cleaner so I bought some and hope to return the garage floor back to its former oil free slab of concrete. I will report back if this works as advertised. The product is ACT Concrete cleaner. ACT Concrete Cleaner

I also need another adjustment on the exhaust system. A minor tweak to the driverside pipe that smacks a cross beam on occasion when going over bumps at speed. Mor importantly, I lost all the nuts on the right header collector so this problem was not resolved after rebuilding the exhaust. This is really bothering me. Does anyone have suggestions?

The last update is that I bought the Yukon 3.73 gears. The shop came back with a price of $650 for labor to swap gears. At this price I decided it was worth investing into a shop press, bearing tools, dial indicators, sanding disc wheel to make my own setup bearings and other misc tools. I estimate $300 in tools. I will then have all the tools needed to replace the front and rear gears in my wifes Wrangler later this summer.

I can't wait to get this installed and tested. My best 1/4 mile time was 17.5sec with 3.08s and the stock tranny. After adding the GV overdrive unit and paddle shifters my 1/4mile time was about 16 seconds. I woudl really love to get this car at 13.5 seconds. That would put a smile on my face.

More to come.

On Friday I took the car to the shop for a new oil pump, oil pan, rear main seal and other minor work to stop all the leaks. The shop estimated one day and about $650 in labor and incidentals and I supplied the big parts. Well they called on Friday to say the work was harding than anticipated. They unbolted the motor but could not lift it high enough to replace the oil pan. I was afraid of this, but they assured me they could do it. Hense the reasonable price.

Well, today I got the call to say they need to pull the whole motor in order to do this work. Now the price is double and they need the car for another week.

I was bummed out earlier today, but then I decided if they are going to pull the motor they might as well do a few things that I would not be able to do on my own. So, I asked them to repaint the block chevy orange and to replace the freeze plugs.

So the work now includes new oil pump, new oil pan, replace 2-piece rear main seal, replace front timing cover gasket, clean and paint the block Chevy Orange and replace the freeze plugs. Is there anything else I should consider?

The goal of this project is to stop all the oil leaks and have a nice clean looking motor. No performance upgrades here other than the Miloden shark tooth oil pump.

Scott
Sometimes while attempting to raise the engine enough to change the pan while in the vehicle, the distributor hits the firewall and damages the distributor. You might want to check that it is OK.

Might as well change the filter if changing the oil.
If changing the coolant/antifreeze, is it a good time to upgrade to safer Peak Sierra. It might be safer for Grandpa's dog. Regular antifreeze leaks are deadly to pets.
Any need/desire to add plug wire routing while engine out?

On painting block, possibly include water pump, dipstick, oil pan (unless "pretty").
If it is easy to get to, it might be worth painting (black) the steering shaft.

Orange?? OK.
Yet my avatar shows a VHT hi temp metallic Pontiac blue that might look good in your engine compartment.
VHT SP122 VHT Engine Enamel; Pontiac Blue; 11 oz. Aerosol; - Walmart.com - Walmart.com

I got the car back today. They did a really nice job and a very fair price considering the amount of work they put into this. They ended up pulling the whole motor and I had them replace a bad freeze plug and they painted the block with a fresh coat of Chevy Orange.

After picking it up I headed out on the road to my work site and it is not right. There appears to be a really bad vibration above 2500rpm. At first I just thought it was vibrating at speed. But after paying more attention I realized that it is not speed related but rather rpm related. I also don;t have the same level of power that i had before.

They questioned the timing and did not have access to teh EFI controller. So, I went back home and opened the program to set the base timing. The timing light was bouncing all over the place and not holding at a single point. It makes me think that somthing is not right. Distributor off a tooth, wires not corrected correctly or somthing like this. Also the driverside exhaiust is leaking. Anyhow I set the base timing as best I could and this did not resolve the problem.

I'm going to call the shop tomorrow and see what they can do.

Hopefully this gets resoved before the weekend so I can install the 3.73 rear end gears.

More to come. Does anyone have any thoughts on the problem?

Here is a look at the motor when they pulled it. I find it impressive that it can look like this and then be back inside the car in two days. That is definately more than I can do. That woudl take me weeks and cost a fortune in tools and equipment that i woudl likely never use again. Money well spent.

I take the car back into the shop tomorrow. Hopefully they can figure out what is causing the vibration.

In the meantime, I picked up the center console so I can install the PCS shifter controller. I am really dissapointed. This did not come out the way I requested. The controller was supposed to be mounted from under the console with the hole cutout so the controller sits flush and only the small section is showing. Instead, even with some serious sanding I was not able to make the interior large enought to properly mount the controller. So, I had to top mount it and it looks stupid. Well, this is just a temporary measure until I upgrade the interior so I am just going to move onto other projects. At least the controller has a dedicated place to be rather then just laying on top of the seat.

Here are a few photos.

Here is the PCS controller mounted to the top of the console. The controller was supposed to fit underneath with a flush mount, but this is not what the builder remembered apparently. There is not way it fits. Not even close. You can see that the flat portion is the same size as the controller outside dimensions. It needs to be about 1/2" larger on all sides so the controller can fit into the backside of the console.



Here you can see the underside. No way for the controller to fit even after I sanded off as much material as I could for the fitment.




Then I used long screws to secure the PCS console onto the main center console.



Cups are back in and now it is placed in teh car. Man this had so much potential.



Here is a final look at teh steering wheel with paddles, GV push buttons and the PCS electronic shifter mounted in the console.

Ok, the big weekend is over and I accomplished some major projects. I will detail items #2, 4 and 5, separately.

1. Got the car back from the shop. They pulled the motor to install an oil pan, oil pump and replace some seals and freeze plugs to stop all the leaks. The car now vibrates and we think it is the flex plate. So, it goes back tomorrow and since they have to pull back the trann I am going to have them install a new Hughes GM5TOW 1800rpm torque converter. They also did something to lock up the Lokar dipstick, so hopefully they can remove it, but they likely have to buy a new one.

2. Rolled the rear fenders for tire clearance. I still have to roll out the front inner fenders. It takes time, but man it works great when you have the right tool. No more fender rubbing in the back.

3. Adjusted exhaust system to stop a thumping sound that woudl occur on occasions.

4. Installed Yukon 3.73 rear gears and went for a 100 mile break-in. I learned lots here. I will share some of my experiences to help others and to remind myself of some importants tips for when I work on my wife's Wrangler differentials.

5. Installed a new black ribbed TH400 tranny pan.

Rolling the rear fenders took me about 4 hours. I am using a Summit Racing Fender roller. It fit the car just barely, but I do have shorter springs. So, it should work with any stock ride height el camino.

For tools I had a fender roller, heat gun and digital temp gauge.



This project takes patience and courage. You really have to get the roller angles right and use a lot of brute force. More than I was expecting.

Here are some photo descriptions:



Fender Rolling Tools-2 These are the tools for the job. I heated up a 5-6 inch section of the fender metal at a time. I aimed for 140F on the inner metal and tried to keep the outer metal around 120F. The heat is needed to keep the paint from cracking. My paint is about 4 months old, so everything held up great. The roller instructions say not to roll double layer fenders, but it worked. Both rear fenders are double layer.




Fender Rolling Rear-3 Here you can see the fender has a 3/4" flat lip. With 275 Nitto tires I get a little scraping on the driver rear tire and a lot on the rear passenger tire as there is less clearance. Here you can see my finger. The tire to fender lip is about 1.5 knucles, aprox 1".




Fender Rolling Rear-6 Thei sis the passenger side and I have 1/2 knuckle of clearance, about 3/8". The bigger problem on this side is that when the suspension compresses the tire hits the inner fender about 2" higher and you can see tire rub marks. I will show you this phots towards the end.




Fender Rolling Rear-8 The fender roller mounts to the lugs using your stock lug nuts. You then adjust the roller angle and tube length as needed to get the angles needed for each pass.




Fender Rolling Rear-9 Checking the outer metal to make sure it does not get too hot. I got the inner fender metal and lip up to 140-160F.




Fender Rolling Rear-11 Driver side lip has been rolled. You can also see two creases up higher on the inner fender. There is no tire rubbing on this side. So, I did not roll it in. It also entends inward toward the center of the car about 2" so it has potential for tire rubbing like the other side.




Fender Rolling Rear-14 this is the passenger side. The fender lip is rolled in, but if you look closley you can see the rub marks on the inner fender.






Fender Rolling Rear-15 This is the final look at the inner fender. I pushed it inward a good 1-1.5". After a test drive today, no more rubbing on the rear fenders even on high speed cornering.

Here is the final result with the tires back on and at road height.



Fender Rolling Rear-16 Finger test is about 2" clearance on the driver side.




Fender Rolling Rear-17 Finger test is about 1.5 inch clearance on teh passenger side. What really made the difference here is that the inner fender was pushed in a lot.




Fender Rolling Rear-18 Final look at drivers wheel and tire clearance.




Fender Rolling Rear-19 Final look at passenger wheel and tire clearance.

I installed a Summit Racing TH400 black ribbed tranny pan to match the Weiland black ribbed oil pan and Edelbrock Fuel injection system and valve covers. Everythign is lookng nice top to bottom. I am having the shop install a Summit Racing black ribbed Flexplate cover tomorrow. Then I will have a matching set.


Sometimes simple installs become a real problem. I read some reviews where people really struggled with the pan and had to do some mods. To my surprise, the pan fit perfectly. The only modz I had to make was to grind a little metal off the GV and Dakota Digital linkage brackets which fit onto the driver side of the pan bolts. No big deal at all.



Photo descriptions:


TH400 Ribbed Pan Install-1 Here is the inside of the pan. The gasket is a perfect fit and very high quality rubber. All holes line up and the bolts hold inside the rubber. I started with 4 bolts and this was super easy.




TH400 Ribbed Pan Install-2 Another trick is to use a very thin coat of gasket sealant to hold the gasket on the pan so it does not slide around when you mate it to the tranny. Once I got the 4 bolts in everything else was a breeze.




TH400 Ribbed Pan Install-3 Here is an underside look at the GV, exhaust with H pipe and tranny pan.




TH400 Ribbed Pan Install-4 Here you can see the matching oil pan too.




TH400 Ribbed Pan Install-5 Final shot from teh front. Fresh Chevy Orange paint and new matching oil and tranny pans. The Flexplate dust cover is also matching and shoudl go on tomorrow.

The last project detail for this weekend is the Rear Differential upgrade from Yukon 3.08 gears to Yukon 3.73 gears. It took me about 20 hours and I learned a lot. I will be much faster for future work. I did run into several problems and I also have some tips to remind myself in the future and for others. You know some stupid stuff that you wish was included in the instructions, but the people that write the instructions are experts and to them some things are just expeted to be understood. Some of the details that I think are really important and worth sharing with others I will mark as "TECH TIP." This will also serve as a reminder for me on the next job.

Specialty Tools Used:
12 ton shop press
6" steel pipe (One for each size bearing. Bearing must spin freely when using the pipe mated to the bearing case).
Oven / heat gun
Bearing puller (failed)
Seal installer
Backlash magnetic dial gauge
Electric 400cfm impact wrench (1200cfm air impact wrench on 125psi air compressor failed)
0-80 inch-pound manual-style (needle gauge) torque wrench
Assorted hand tools, hammers, calipers and torque wrenches


Here is the photo description:

Yukon 3.73 Gear Install-19 I made a setup sheet to track my progress and to simplify the instructions. I would refer to the Tukon instructions when needed, but the setup order and adjustment tips are all on my sheet. Here is a quicklist of Setup Steps:
1. Oil everything
2. Pinion Trial
3. Set Pinioin preload tension
4. Initial carrier setup with shims
5. Carrier needs to be tight. Drive side shim determines the backlash
6. Check Pattern
7. Adjust as needed with additional trials.




Yukon 3.73 Gear Install-1 This is a GM 8.2" rear end that was stock with highway gears, 2.56. In 2017 I installed a Yukon Posi carrier and 3.08 gears. I still want (need) more holeshot power so I finally decided to add a Gear Vendors Over/Underive to my TH400 and to swap out the gears to Yukon 3.73. This gives me the holeshot power (hopefully) and still a drivable car in overdrive at 70-90mph. In this photo I pulled off the cover and started some cleanup with the 3.08s inside.

I only had about 2000 miles on these 3.08s so my plan was to keep the carrier bearings and races intact and only change out the pinion bearings. The bearings used on the 3.08s were identical to the 3.73s so I checked all tolerences and decided to keep the races in place for these. I did replace the pinion seal and I was planning on pulling both bearings off and to bore them out for setup bearings. Most of this plan worked, but not all of it. I was not able to remove the larger pinion bearing.




Yukon 3.73 Gear Install-5 The first step was to remove the carrier and install the new ring gear. This was straight forward, but I read other installs and watched videos where the bolts are LH threads. So, I did waste some time tightening the bolts instead of loosening them with an impact wrench.
TECH TIP: Yukon uses standard RH threaded ring gear bolts.




Yukon 3.73 Gear Install-6 The smaller Timken pinion bearing came off when I punched the pinion gear out of the differential case. Time to make a setup bearing.
TECH TIP: Use a flap wheel attached to a drill press. I held the bearing in a vise with Park Tool vice attachment designed to hold bike hubs and axles. This made short work of honing the bearing, about 3 minutes.




Yukon 3.73 Gear Install-7 I would hone then check my work. The setup bearing shoudl freely slide onto the pinion shaft, but shoudl have no play at all when shaking the bearing.




Yukon 3.73 Gear Install-8 Slips on like butter. Smaller bearing from 3.08 pinion is ready for action.




Yukon 3.73 Gear Install-9 The jaws of this bearing remover tool were too thick to safely grab under the bearing. So, I used a dremel to work it down and when in place the bearing would spin, but as soon as I placed it in the shop press, I distored the bearing so I stopped to prevent more damage. This bearing puller did not work for me.
TECH TIP: I bought the larger pinion bearing from Oreilly's for $20. I then honed this out to make a setup bearing. If you don't have an old pinion with matching bearings, you can just buy new cheap bearings and hone them. Yukon want $160 or so for their setup bearings.




Yukon 3.73 Gear Install-10 In about 20 minutes (after I bought the new larger bearing) I had both bearings honed and ready for action on the new 3.73 pinion gear.




Yukon 3.73 Gear Install-12 Now is time to add some shims (I started with the recommend 0.74mm (0.030) and slip on the larger bearing. Insert the pinion into the case. Now hold in place with one had and then slide on the smaller bearing from the other side. Then install the yoke, washer and new nut. Be careful here but use your impact wrench to set the tension. You will need a small inch pound manual torque wrench. The tension should be 12-15 inch pounds when rotating the pinion. Do not measure the initial force required to turn the pinion but rather the rotational tension.
TECH TIP: Do not use the pinion seal or crush sleeve during setup. You must have setup bearings otherwise you won't be able to saely remove your expensive bearings.
TECH TIP: I always used the new nut for setting the pinion bearing tension and I used the old nut when pounding the pinion out of the case for the next setup trial.

Yukon 3.73 Gear Install continued


Yukon 3.73 Gear Install-13 Once the pinion is set now you can move on to the carrier setup. On each side of the carrier you will need shims. In this step you will set the backlash. This part took me longer than it should have. I spent a lot of time sorting all my shims and measuring their thicknesses. This is also the part where I was stupid and the instructions did not tell newbies how to setup the shims. My differential uses an "Outside Shim Design" The Yukon master install kit includes a bunch of shims with assorted thickness. It also includes two sets of sandwhich shims. These looked wierd to me and it took me awhile to figure out that you take those skinny slices of meat and stick it into the center of your two thick bread slices. I was an idiot and tried to slide those skinny shims between the carrier race and the housing seat. I was bending them of course.
TECH TIP: Skinny shims are inserted into the sandwich shims to protect them from damage.
TECH TIP: The driver side shim determines backlash (.006-0010). The passenger side is used to keep the carrier tight inside the case. You must use a soft face mallet to set these in place. If it wobbles or falls out easily, it is too loose.





Yukon 3.73 Gear Install-14 This is the sandwhich shim stuffed with a few thin shims on the inside to protect them. I do not have a picture of the backlash dial indicators or this step. But, this took me the longest time to get right. Once I had the backlash set at .008 I was ready to proceed.
TECH TIP: When the carrier will not rock out of the case then you know it is tight enough. In order to remove the shims use a 90 degree HD pick and insert into the case hole on the passenger side and pull the shim stack out. Then everything can be removed for the next trial.




Yukon 3.73 Gear Install-15 Once the pinion tension and backlash is set it is time to check the pattern.Paint up the gears and rotate the gear.
TECH TIP: Rotate the ring gear not the pinion gear.




Yukon 3.73 Gear Install-16 This is my pattern on the first attempt. I got very lucky here.




Yukon 3.73 Gear Install-17 Once the trials are complete set everything aside and record your final shim stacks for the pinion bearing and carrier shims. Now it is time to press on your large pinion gear. Put on the shims, heat up the bearing, slip into place and then press into final seated position. Now add the cruch sleeve and set this loaded pinion gear next to the differential and ready to grab.
TECH TIP: The oven works! Heat bearing to 300 degrees for 10 minutes. I did not freeze the pinion gear like some people say to do. Then slip the bearing on. Mine slid down to the base. I really think I could have done this without a $150 shop press! I could have used the pipe and a 4 pound mallet to seat the hot bearing into place.





Now insert small bearing into the differential case and prep / pound the pinion seal into place.
TECH TIP: Once the seal is in place that bearing stays there and cannot come out without damaging the seal.
TECH TIP: Use a heat gun and apply heat to the bearing from the case cover opening. Do not get the seal too hot. Apply heat to the bearing to about 180F. Now you can slide the pinion gear (with crush sleeve) into position. The hot smaller bearing will slide partially onto the shaft enough to allow you to get the yoke, washer and nut threaded. Without heat I could not get the nut onto the threads of the pinion gear.
TECH TIP: Use electic impact wrench to add tension. Use manual torque wrench and go slow. Raise tension to 12-15 inch pounds on rotation.






From this point on eveything goes really fast. The hard part is over. Install the carrier with shim packs. Tap into position. Add carrier caps and torque to spec. Check final backlash and pattern. Record these.

Insert axles and install C-clips. Insert locking pin and bolt.

Install gasket and pan cover. Torque bolts to spec. Add differential oil. Mount wheels and perform gear break-in procedure as stated in the manual.

These final steps took me about 2 hours. It took about 18 hours for setup portion. I really think I could do this again in about 6-8 hours per differential. Maybe even less. I do not think I would use the press either. Adding heat to the bearings is like magic.

When I have time in teh next few days I am going to go back to that 3.08 pinion with the installed larger bearing and apply heat to just the bearing with a heat gun. I think I can get the bearing puller jaws onto the bearing enough to seperate the bearing from the shaft with maybe a blow from a hammer onto the backside of the tool to knock the bearing off without a press. If this trick works then heat it is for now on!!! And I won't have to buy any setup bearings at all for future gear swaps.

I forgot to include my setup notes and final shim stack specs. WootWoot, got it done. I have done the 20 mile and 100 esay drives to break-in the gears. Once I get the car back from the shop I can begin faster accelerations and really see how I like the new gears. At 500 miles I need to replace the diff oil.