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Sat May 11, 2019 1:52 pm

A good VW friend gave me a mostly complete non-running dual-port engine several years ago. I tore it down and will use the engine case for a mild stroker build. The other parts are being redone as time and interest permits.

I started with the intake manifold. Degreased it, then cleared out the carbon-blocked preheat pipe with a section of handbrake cable in a variable-speed drill. After the degreasing, the rust on the preheat pipes are evident. Left pipe shown; right pipe was similar. I wanted to try to improve the appearance of the manifold and especially the preheat pipe with some basic home tools.

Here are all the tools I used. Resorted to the wire wheel on the angle grinder after the bead blaster cabinet at work was clogged and ineffective. I used the face shield, gloves; wore a long-sleeve sweatshirt and work jeans while cleaning the manifold, because the wire wheel can sometimes fling individual metal bristles off.

The wire wheel worked very well, revealing of alot of rust pitting on the preheat pipes.

Using the grinding wheel on the angle grinder, I skimmed the preheat pipe surfaces to grind down the corrosion "craters" down level. I pulled the grinder towards me with the grinding disc at an upward angle to minimize the digging that the disc would do into the pipe surface. Efforts were on the top and rear-facing sides of the manifold which would be in direct view when installed on the engine. Back of the pipe (facing front of the car) and underside were also ground down but not as diligently. Toughest part was the tight underside corner of the pipe. Attachment flange was not important because it is hidden when the rear breast plate and the small pipe cover tins are in place.

To smooth the grinding marks off I used the metal file. Worked it along the direction of the pipe to make the most use of the length of the file blade to achieve the best levelness. Used the half-round file surface on the underside tight curve of the pipes. Then used the 80 grit emery cloth strips to give final smoothing. Ran the cloth side to side over the pipe surface like shining shoes with a polishing cloth. Spent about 1/2 hour on each preheat pipe with this filing and sanding.

When I was satisfied with the evenness of the preheat pipe surfaces, I wiped the entire manifold with Prep-Sol cleaner, and applied 2 coats of POR-15 intake manifold high-heat grey paint using the dense foam roller. Waited until the first coat was dry overnight before applying the 2nd coat. The paint left a nice uniform surface finish. I got the idea for a foam roller instead of a simple foam pad or bristle brush from recent Samba responder carnut63 who was redoing his 36hp manifold. I'm very satisfied with the makeover results.

The back (frontward facing) side of the left preheat pipe shows the light pitting usually seen when other manifolds are sandblasted and ceramic coated. I did file the rust pits down somewhat, but did not bother to fully smooth the surface because it's out of sight when the manifold is in place.

Sat May 11, 2019 5:54 pm

Well done. It will look great installed.

Sat May 11, 2019 6:13 pm

Nice job.

Sat May 11, 2019 7:42 pm

Yeah looks good man. Quality work takes time and most people don’t have the time.

Sun May 12, 2019 4:55 am

Beautifully done Rome!

Sun May 12, 2019 5:59 am

The only down side to doing this kinda work on those heat pipes is now they are paper thin in many places... the internal corrosion plus external and all the clean up equals paper mache tubing. Been there, done that.

Sun May 12, 2019 6:21 am

In the big scheme of things it would probably last many more years before any thin area would present a problem, it sure looks nice good on you. :D

Sun May 12, 2019 7:22 am

Oh , don’t get me wrong... it’s nice work and looks great... but in my experience (30+ years), they’re already thin with corrosion from the inside, after you clean all the scale out and then grind the corrosion flat on the OD... they’re very thin. Got a cleaned up one on my car right now that’s perforating.

Sun May 12, 2019 8:47 am

Would getting the manifold powder coated help the pre-pipes last longer?

Sun May 12, 2019 9:58 am

I think a lot of the corrosion takes place on the inside. I’ve played with the idea of making new tubing for some of mine doesn’t seem too hard. I typically deal with older intakes (40hp) so they’re 10-15 years older and more abused than the OP’s intake....I do apologize if I’ve taken away any steam from the original post. The intake does look really nice and I’m sure he’ll get plenty of use out of it. Twice I’ve done the same work he’s done and later noticed rust coming through the paint and then the intake starts failing in heat riser tubes.

Sun May 12, 2019 10:06 am

APPLEGREENVW wrote: Would getting the manifold powder coated help the pre-pipes last longer?

No.

Thu Aug 22, 2019 5:50 pm

Finished the conversion from Kadrons to the stock single carb in my '77 Std. Beetle tonite, and started up the engine. This is the intake manifold per my thread here. I still need some minor tuning which I'll do in the coming days.

I also redid the stock air cleaner I had since '92 that was from a '71 parts Beetle. Semi-gloss black Rust-O-Leum spray can, and clear-coated clips. Carb is a German Solex 34-PICT 3. Distributor is a DVDA with the retard circuit blocked, and paint detailed. Engine perimeter seal is the foam H profile from 70's Type 2 that is pressed into the gap. Crank degree pulley is the single-degree marked unit on which I painted the center using my paper dish mask technique. https://www.thesamba.com/vw/forum/album_search.php...t_dir=DESC

Thu Aug 22, 2019 6:50 pm

Nice work, that's a good looking engine!

Thu Aug 22, 2019 7:59 pm

Rome
Why did you go back to a stock carburetor? Is this just a spare engine?

Thu Aug 22, 2019 8:02 pm

Rome wrote: Finished the conversion from Kadrons to the stock single carb in my '77 Std. Beetle tonite,
Stock 77 had Fuel injection.

Fri Aug 23, 2019 3:44 am

Glenn, when I bought the '77 in '92 (seen for sale at the Litchfield VW meet at Litchfield Inn, CT in '92) the PO had done much work to the car, and to the engine. It had a 2110 with dual Dell'Orto 45 DRLAs, Engle 125 cam, and large-valve heads. Over the years I tamed down this engine or replaced it due to various reasons. Last version was a stock 1600 dual-port with Kadrons, stock-valve semi-hemi'd fuel injected heads, and 1.4:1 rockers.

This stock single-carb configuration is only a temporary experiment. The long block remains as above.

Fri Aug 23, 2019 8:08 am

Which exhaust system are you using ?

Fri Aug 23, 2019 2:14 pm

Apple, I chose a EMPI single-tip GT, #3487, at bottom left here: http://vwcatalog.empius.com/vwcatalog/2018/209.html

First saw this muffler on a NJ friend's split window Beetle a few yrs ago, which had a 1600 engine. On that car the muffler single tip looked almost "proper". The original FI engine in a '77 also had a single tip exhaust that exited the body in the same general area, though with a bulged apron bottom.

I stripped off the black "shipping" paint using paint stripper, plastic scraper, and brass bristle brush. Once clean, wiped it with Prep-Sol and painted it with VHT cast iron grey. Took a full can to apply the 3 light coats. I wanted an exhaust that exited below my apron's bottom edge, because a PO had filled in the cutouts ('73 style apron retroftted). I had a 1 3/8" header with single quiet muffler which worked well and sound great, but again, I wanted something with slightly more stock-ish appearance. Left upper pipe comes back too straight. When I installed a German rear breast plate, there was not enough space to slip the fresh air hose past it and route it into the left heater box. Grrr. So I cut out an approx. 3/4" deep "crescent" from the left hole in the plate to move the entire hole rearward, riveted in a matching patch, and painted it all semi-gloss black. The hose still contacts the left upper muffler pipe, but needs only a slight bit of flattening the round profile.

This muffler was already pre-drilled for carb preheat, and I used a small-hole and large-hole gasket at the joints to induce a pressure difference and heat flow thru the intake manifold pipe.

I tried using a Tri-Mil hotdog dual-tip muffler which I had on my Ghia for a few years. The tops of the outlet pipes contacted the underside of the apron, so that was a no-go. The hotdog's upper left pipe bends outward more than on the EMPI so that the fresh air hose went on without needing to modify the breast plate. Too bad the EMPI's upper pipes don't curve out more; there's plenty of lateral room for that in the engine bay.

Fri Aug 23, 2019 2:33 pm

So using the large and small hole pre-heat gaskets on that muffler, helps keep enough heat moving in the pre-heat tube? From what I have read aftermarket headers/mufflers need to be modify to get the proper heat.

https://www2.cip1.com/ProductDetails.asp?ProductCode=C13%2D3487