So much beauty and inspiration. Your work is art. Thanks for taking us along on this journey.
Engine rebuild and engine bay resto thread - 2240284 '72 CS
- Thread starter Stevehose
- Start date
WOW, Steve! It's so comfortable resting my eyes on those pictures, beautiful job!
Now on to tuning. Here is my latest curve. After deep diving into the history of vacuum advance (ported vs. manifold) and pouring over the M30 advance curve specs ad nauseum, as well as taking into account 10:1 compression/3x Webers, Schrick cam, and headers, I have landed on the following setup for now:
-static advance set at 12 degrees.
-mechanical curve all in 33 degrees at 2800 rpm (this will likely change with dyno)
-12 degrees of manifold vacuum advance for a total idle advance of 24 and cruise advance of 45.
The engine loves idling and accelerating from 25, it would like more but I am holding it here. To avoid detonation, under heavy acceleration the vacuum advance drops out leaving only the mechanical curve. Around town 99% of my driving (and probably yours too) is at partial load and the vacuum portion makes a significant difference in performance. I tested this by having my vacuum advance kick in at various rpm's - once it does you can feel the engine perk up. Mash the throttle and the vacuum drops out and off you go towards the red line. Apparently this is why, before the era of emissions band-aids, manifold vacuum was used. Ported vacuum came along to eliminate this extra advance at idle in order to burn the exhaust hotter and performance suffered - no thank you DOT.
This curve was determined by lots of driving in all gears and conditions. For example, it is harder to get to 0 vacuum in 1st and 2nd gear than the higher gears. So you need to compromise on when you want the advance to drop out. I have it starting to drop out at 84 kP (-4.72 Hg) and gone completely at 91 kP (-2.65 Hg). This allows it to safely drop out in low gear and still allow 4th and 5th gear cruising without dropping out too soon. In 4th and 5th gear, a slight touch of the throttle to pass a car has it dropping out right away. Your engine will likely be different on the above data points but the fundamentals are the same. I have no advance below 600 rpm to aid in cranking (I think the 123 programs no advance below 500 rpm anyway) and my sluggish hot Weber starts have seemingly improved. If I weren't running vacuum advance I would set my static/idle advance to 20 or so and keep the mechanical curve as is.
-static advance set at 12 degrees.
-mechanical curve all in 33 degrees at 2800 rpm (this will likely change with dyno)
-12 degrees of manifold vacuum advance for a total idle advance of 24 and cruise advance of 45.
The engine loves idling and accelerating from 25, it would like more but I am holding it here. To avoid detonation, under heavy acceleration the vacuum advance drops out leaving only the mechanical curve. Around town 99% of my driving (and probably yours too) is at partial load and the vacuum portion makes a significant difference in performance. I tested this by having my vacuum advance kick in at various rpm's - once it does you can feel the engine perk up. Mash the throttle and the vacuum drops out and off you go towards the red line. Apparently this is why, before the era of emissions band-aids, manifold vacuum was used. Ported vacuum came along to eliminate this extra advance at idle in order to burn the exhaust hotter and performance suffered - no thank you DOT.
This curve was determined by lots of driving in all gears and conditions. For example, it is harder to get to 0 vacuum in 1st and 2nd gear than the higher gears. So you need to compromise on when you want the advance to drop out. I have it starting to drop out at 84 kP (-4.72 Hg) and gone completely at 91 kP (-2.65 Hg). This allows it to safely drop out in low gear and still allow 4th and 5th gear cruising without dropping out too soon. In 4th and 5th gear, a slight touch of the throttle to pass a car has it dropping out right away. Your engine will likely be different on the above data points but the fundamentals are the same. I have no advance below 600 rpm to aid in cranking (I think the 123 programs no advance below 500 rpm anyway) and my sluggish hot Weber starts have seemingly improved. If I weren't running vacuum advance I would set my static/idle advance to 20 or so and keep the mechanical curve as is.
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Looks awesome Steve!
Some of the products I had good results with:
-The Polaris paint I had mixed into spray cans is Debeer 500, the silver flake is tiny and looks oem. Goes on great, dries fast, and takes the clear nicely. Highly recommended and thanks to @wkohler for this tip. Also Spraymax 2k gloss Glamour clear and their primer are good stuff. Wear a respirator for these!
-My go-to satin black spray paint had been SEM 39143, however as good as it goes on I found that it is inconsistent regarding gloss level from can to can, sometimes looking too flat (probably from lack of sales volume). The best I used is VHT SP652 Epoxy Satin Black. It is a little more difficult to work with as it can easily run on you if you put too much on at a time. I am a very impatient spray painter, the technique I had to struggle to do was to VERY lightly dust spray the first coat, almost transparent-like. Allow to dry for at least 10 min then do successive VERY LIGHT coats until complete. Don't touch for 48 hours. Looks amazing, maybe a little glossier than SEM satin but after a while in the elements it settles in perfectly. More durable and easily available too.
-Isopropyl alcohol and acetone in spray bottles for cleaning. I used 3 gallons of iso and 2 gallons of acetone for this project.
-The best grease cleaner I found is Marine Grez-Off from West Marine et al. Blows Simple Green out of the water and it didn't ruin any paint or hurt the aluminum. Test it first of course:
www.westmarine.com
-I like POR-15's undercoat spray, goes on nicely and looks great:
por15.com
-Cerakote wipes for the plastic trim parts. So far so good:
-Rustoleum 2x Ultra Cover satin and gloss clears for various parts work very well. The satin is amazing, you can't really tell it's on, it just looks real.
-Permatex muffler sealer. Using a smoke machine, I found MANY leaks in the exhaust. This stuff goes on like toothpaste, gives just enough time to assemble, then seals it shut.
www.permatex.com
-Long q-tips. I've used hundreds of these:
-And of course, where would we be without JB Weld? I buy the jumbo size LOL. Their clear 5 min epoxy is good too.
-More as I remember!
-The Polaris paint I had mixed into spray cans is Debeer 500, the silver flake is tiny and looks oem. Goes on great, dries fast, and takes the clear nicely. Highly recommended and thanks to @wkohler for this tip. Also Spraymax 2k gloss Glamour clear and their primer are good stuff. Wear a respirator for these!
-My go-to satin black spray paint had been SEM 39143, however as good as it goes on I found that it is inconsistent regarding gloss level from can to can, sometimes looking too flat (probably from lack of sales volume). The best I used is VHT SP652 Epoxy Satin Black. It is a little more difficult to work with as it can easily run on you if you put too much on at a time. I am a very impatient spray painter, the technique I had to struggle to do was to VERY lightly dust spray the first coat, almost transparent-like. Allow to dry for at least 10 min then do successive VERY LIGHT coats until complete. Don't touch for 48 hours. Looks amazing, maybe a little glossier than SEM satin but after a while in the elements it settles in perfectly. More durable and easily available too.
-Isopropyl alcohol and acetone in spray bottles for cleaning. I used 3 gallons of iso and 2 gallons of acetone for this project.
-The best grease cleaner I found is Marine Grez-Off from West Marine et al. Blows Simple Green out of the water and it didn't ruin any paint or hurt the aluminum. Test it first of course:
Marine Grez-Off | West Marine
Check out our Marine Grez-Off and more from West Marine!
www.westmarine.com
-I like POR-15's undercoat spray, goes on nicely and looks great:
Rubberized Under Coating
Provide superior adhesion to metal surfaces with POR-15's Rubberized Undercoating. This rubberized paint for metal protects against moisture, salt, & more.
por15.com
-Cerakote wipes for the plastic trim parts. So far so good:
-Rustoleum 2x Ultra Cover satin and gloss clears for various parts work very well. The satin is amazing, you can't really tell it's on, it just looks real.
-Permatex muffler sealer. Using a smoke machine, I found MANY leaks in the exhaust. This stuff goes on like toothpaste, gives just enough time to assemble, then seals it shut.
Permatex® Muffler & Tailpipe Sealer - Permatex
www.permatex.com
-Long q-tips. I've used hundreds of these:
-And of course, where would we be without JB Weld? I buy the jumbo size LOL. Their clear 5 min epoxy is good too.
-More as I remember!
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It’s a thing of beauty, Quite obvious you don’t have OCD. 
tdgray
Well-Known Member
Absolutely amazing… attention to detail is impeccable.
Steve, its even more than we have come to expect from you - EXCELLENT work !!! i noticed the red fan, and it looks great on your car.
i have had the same issue with SEM, so i always keep a can of clear satin around to make sure it has the right effect.
i have had the same issue with SEM, so i always keep a can of clear satin around to make sure it has the right effect.
Awesome attention to detail!
Breiti
Well-Known Member
A clean under floor or engine bay like that makes me ho....y
Sure, you wrote it anywhere, but
Are those 40 or 45 DCOE ?
Wonderful job
Breiti
Sure, you wrote it anywhere, but
Are those 40 or 45 DCOE ?
Wonderful job
Breiti
DCOM 40 - the last Italian Weber before moving to Spain. The best features being vacuum ports for each barrel and the adjustable accelerator pump which they copied from Delorto.
Breiti
Well-Known Member
Great, so you have the bologna carbs
Breiti
Breiti
Having just rolled 100k miles (62k in my posession), the projects continue with a few underside ones which will have the car on jack stands in the coming weeks.
First is resealing and replacing some bearings in my original 3.64 differential which will go back in place of the 3.45. The 3.45 is nice but too long for my driving area, and with the 5 speed I find it unnecessary. I am doing the 3 seals, large case o-ring, and the 2 outboard bearings. The pinion and inner bearings are smooth and quiet so I am not going to tempt fate by going deeper. Not too difficult to disassemble, a bearing puller is necessary for the input flange but otherwise so far it's straightforward as per the manual. I had to grind down the tip of a 30mm socket to get the pinion nut off despite it being a "thin walled" one. I also used Hylomar on the sideloader case plate and top vent gasket. Waiting on the bearings then reassemble and paint:
Along with this, I've had the Pirelli Cinturato CN36 for 7 years and >35k miles and love them. However, they are aging and wearing out (not helped by the negative camber plates). They are balding in front:
I had a frightening accident 40 years ago when an old tire blew out at 70mph while on the Causeway bridge in New Orleans (25 miles across), I bounced from wall to wall and almost went over the short guard rail before coming to a stop. For 10 years the yellow paint of my totaled '71 Mustang convertible was still showing on the sides of the bridge to remind me. Needless to say, I am very cautious of driving on tires that have a whiff of sketchiness. Unfortunately, the 205 CN36's are not available, according to Longstone, until September (Lucas has no eta). I want period looking tires and can't wait that long so I grabbed my ankles and ordered the XWX's from Longstone and they are en route. With the dollar pretty strong and a credit card that doesn't charge the Visa conversion fee, I bought 4 in Pound Sterling for about $200 less than any other vendor here stateside. Now that I've somewhat recovered from the cost shock, I'm looking forward to seeing how the XWX will look vs. the CN36. I suspect they will hold their own in the looks dept.
So the old ones will come off and I will strip to bare metal the 5 hole Alpinas and repaint them. I've done this before on a couple previous sets (and have touched these up in 2021) and am looking forward to giving them a complete resto. I suspect the layers of paint over the years is why the Alpina embossing is not as visible as I'd like. We'll see.
I had success with the Spray Max 2k spray paint products for the engine compartment so I am going with their 2k primer and good old Krylon Dull Aluminum for the silver (I think Wurth has too much metal flake and it doesn't apply like a $25 can should). Then I will finish with 2k clear for better durability and brake dust resistance, either gloss or satin TBD. I have the lazy susan for spinning and painting, and a paper hole cutting device for the black center templates like @paul cain just did, I will use my trusty VHT satin black for this. Once finished they will go back to the shop to be mounted and balanced from the inside and with new metal valve stems.
Any thoughts on gloss vs. satin clear for the wheels?
EDIT: @Wobdog recommends Cerakote for clear so I will look into that.
First is resealing and replacing some bearings in my original 3.64 differential which will go back in place of the 3.45. The 3.45 is nice but too long for my driving area, and with the 5 speed I find it unnecessary. I am doing the 3 seals, large case o-ring, and the 2 outboard bearings. The pinion and inner bearings are smooth and quiet so I am not going to tempt fate by going deeper. Not too difficult to disassemble, a bearing puller is necessary for the input flange but otherwise so far it's straightforward as per the manual. I had to grind down the tip of a 30mm socket to get the pinion nut off despite it being a "thin walled" one. I also used Hylomar on the sideloader case plate and top vent gasket. Waiting on the bearings then reassemble and paint:
Along with this, I've had the Pirelli Cinturato CN36 for 7 years and >35k miles and love them. However, they are aging and wearing out (not helped by the negative camber plates). They are balding in front:
I had a frightening accident 40 years ago when an old tire blew out at 70mph while on the Causeway bridge in New Orleans (25 miles across), I bounced from wall to wall and almost went over the short guard rail before coming to a stop. For 10 years the yellow paint of my totaled '71 Mustang convertible was still showing on the sides of the bridge to remind me. Needless to say, I am very cautious of driving on tires that have a whiff of sketchiness. Unfortunately, the 205 CN36's are not available, according to Longstone, until September (Lucas has no eta). I want period looking tires and can't wait that long so I grabbed my ankles and ordered the XWX's from Longstone and they are en route. With the dollar pretty strong and a credit card that doesn't charge the Visa conversion fee, I bought 4 in Pound Sterling for about $200 less than any other vendor here stateside. Now that I've somewhat recovered from the cost shock, I'm looking forward to seeing how the XWX will look vs. the CN36. I suspect they will hold their own in the looks dept.
So the old ones will come off and I will strip to bare metal the 5 hole Alpinas and repaint them. I've done this before on a couple previous sets (and have touched these up in 2021) and am looking forward to giving them a complete resto. I suspect the layers of paint over the years is why the Alpina embossing is not as visible as I'd like. We'll see.
I had success with the Spray Max 2k spray paint products for the engine compartment so I am going with their 2k primer and good old Krylon Dull Aluminum for the silver (I think Wurth has too much metal flake and it doesn't apply like a $25 can should). Then I will finish with 2k clear for better durability and brake dust resistance, either gloss or satin TBD. I have the lazy susan for spinning and painting, and a paper hole cutting device for the black center templates like @paul cain just did, I will use my trusty VHT satin black for this. Once finished they will go back to the shop to be mounted and balanced from the inside and with new metal valve stems.
Any thoughts on gloss vs. satin clear for the wheels?
EDIT: @Wobdog recommends Cerakote for clear so I will look into that.
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Nice Vice.
Earlier this week, I picked up that set of CN36s my TVR buddy offered to you. They have lots of tread left, but as you know are getting old. They will be going on the 635csi project car. He replaced them with new ones from Longstone, so the batch he tapped into must have sold quickly.
I vote Satin Clear.
Earlier this week, I picked up that set of CN36s my TVR buddy offered to you. They have lots of tread left, but as you know are getting old. They will be going on the 635csi project car. He replaced them with new ones from Longstone, so the batch he tapped into must have sold quickly.
I vote Satin Clear.
Satin duly noted. I can't believe it's been 7 years since their inaugural road trip to the VIntage and the E9 lair with you and the gang!
That was a great trip (other than being labelled as snobs by the Vintage admins).
We need to get something together.