I really dig this seiries from a guy who has done it all in the VW world. One respectful comment about the manifold porting and leaving the 'ribs' under the carb. I disagree with the concept. I read this idea in a book I bought about hot rodding a Chrysler Conquest motor I worked on. The author said to leave the intake ports rough because it would create a 'barrier layer' so fuel would not stick to the manifold. That car ran like a dog compared to my bug where I used Cratex wheels to polish the ports like glass. My theory for the plenum manifold shown is, if you polish it like a mirror, the fuel will have no ridges to stick to and will be carried out of the manifold by the rushing airflow and will be mixed by natural turbulence. The ridges will create 'swirls' under the carb that will act as a limit of the air flowing past the swirls (eddy currents that resist flow under the carb).
I was glad to see you do that demonstration with both single and dual ports. Ever had much trouble with dropping valves in the past. I have been really lucky, but do know people who have dropped valves on the same motor in the same month,BRUTAL......
Power's in the heads, such a true statement. Take any new aftermarket head and you will find poor valve seat transitions and rough casting marks. Just taking a dremel and smoothing off all those edges with sanding rolls makes a difference. They also skip a proper 3 angle valve job like the original heads, it's all lost flow and power. Thanks for sharing Mike, head porting is such an important part of engine building that is frequently overlooked IMO. Always so many things to still learn.
Good idea with the ridges in the upper intake. Don't know if they still make them but years ago a company made screens. It was usually a 1 inch spacer plate under the carb, then the screen between the plate and the intake. Was to help ATOMIZE the the fuel for better air/fuel mixture. So the ridges you added will help the fuel ( splash ) in a sense. Causing it break into smaller droplets. Excellent idea.
I think I see where you’re going with this Mike. This should be a good primer for the VW engine builder novice / low buck builder. Maybe a single port dual relief, doghouse cooled single carb with vacuum advance and maybe a pertronix? I’m looking forward to it.
total build budget so far 100 bucks. DOnt have a spare dog house so I am using stand up. but it will work. cant wait to fire it monday. should run super strong for a single. We do have some dual port heads but carb supply is dwindling. I will upgrade it from only swap meet finds. to show it can be done.
That doghouse would definitely be a future swap meet upgrade, and I’d love to see you push the performance limits of single port heads. By the way , the name “Poverty Special” is the way to go!
Hi Mike and all you fellow watchers. I admit to having different preferences and ideas. See, I don't fancy high displacement and powerful engines. I was looking very hard for a 1300 dual port engine (AB engine code) and finally found one. The heads on those have small valves which again is where I'm weird, coz I like that. I would love to build on that base and go with a 74 mm counterweighted crank, an Engle 100 cam, stock 77mm cylinders and pistons, 34 pict carburator and stock exhaust. This will make it possible for me to avoid having to spend money on machine work, which is extremely expensive over here AND it will give me that small displacement engine, but tuned and hopefully a little more agile than the stock engines. I want to attempt some porting to those 1300 dual port heads. I should be able to do the porting as well as the mild clearensing neccesary for the 74 mm crank myself, using hand-held air- tools, shouldn't I? Will follow the budget build with great interest. Best Regards Lars Karlsson
you could do that if the case is in good shape Like no line bore needed. the 74 is almost a drop in with clearanced rods. just a little dremel. We will be doing one pretty soon if the case I took into the machine shop makes it.
Back in early 80s when 40X35 Autolineas were 37.50 , I worked on a Seat and guide Machine . And with it I could have done most anything. Knock out the guide and spread the valves apart by putting a fatter guide and larger seat. But We did not mess with VWs. The Opel club had us to do 11 motors that had the works on them.
wow looking at mills right now lets see maybe plus we are. Always wanted a valve grinding machine too. lets see if the old craigslist will deliver. ha ha.
@@Mikefngarage Do not kick me. I could have got Auto Machine shop but i told my old boss that times had changed.Most guys want a crate motor. Joe had alot of VW shit. Had a line bore box with a extra set of cutters that was still in their wrappers.
SP all day baby!!...lol... meaning that I should have saved up more for dual port..hahaha. Are miss match heads (part numbers) critical? I know its probably a dumb question.
I'm curious if you think a mild port job, like you show in the video, would make any difference for a factory fuel injected, 1600, dual port in a '78 Beetle convertible. At some point I will be rebuilding the engine, and from what I've read, there isn't much I can do to squeeze more horse power out of it if I keep the fuel injection (which currently works great, and I love).
Not sure who told you that but they were filling your cup with bull crap. Get some displacement a cam and a mild port job and the fuel injection will work even better than stock.
yea a little. and it can help. the corner on the exhaust is pretty tight. Not going to give you much power though. Porting mostly helps with higher RPM and those 40s are torque low RPM. too many RPM in there and you better check the oil pump size. Stock was a 17mm which is barely enough oil supply for 4000 RPM. 1600 rockers are a good upgrade but remember there are no cam bearings in there. If there are (upgraded at some point) you could put 1.25 rockers on it possibly. but rotate and check and make sure the springs dont bottom out. on the 1200 I run stock exhaust too. maintains the torque best.
@@Mikefngarage Thanks for the golden advice! I’ve got a 110 cam with cam bearings and upgraded the engine with a big bore kit to nearly 1400cc. I always keep the oil level high since I once ran it too low from a leak and ended up snapping the crankshaft. This engine is an experiment, so I really put it through its paces-daily driving, off-roading, etc., in my Baja Bug. On the freeway, I can hit 82 mph with some wind-breaking help from other cars, but usually cruise at 65 mph. Exactly like you said, I found that an independent dual exhaust hurt my torque, so I went back to the stockish exhaust. Just trying to figure out what else I can do to it. Currently I'm trying to design an adapter for a 34pict carb. I have the one that goes the other way around (adapting a smaller carburetor to bigger manifold) but you can't just flip it, I tried. so I guess I'll try to port the exhaust see what happens. Thank you!
@@barrioscorona215 100 cam would work better. 26mm pump on there. bore the oil intake a bit too. But if you power it up too much the crankshaft will break again.
I really dig this seiries from a guy who has done it all in the VW world. One respectful comment about the manifold porting and leaving the 'ribs' under the carb. I disagree with the concept. I read this idea in a book I bought about hot rodding a Chrysler Conquest motor I worked on. The author said to leave the intake ports rough because it would create a 'barrier layer' so fuel would not stick to the manifold. That car ran like a dog compared to my bug where I used Cratex wheels to polish the ports like glass. My theory for the plenum manifold shown is, if you polish it like a mirror, the fuel will have no ridges to stick to and will be carried out of the manifold by the rushing airflow and will be mixed by natural turbulence. The ridges will create 'swirls' under the carb that will act as a limit of the air flowing past the swirls (eddy currents that resist flow under the carb).
I was glad to see you do that demonstration with both single and dual ports. Ever had much trouble with dropping valves in the past. I have been really lucky, but do know people who have dropped valves on the same motor in the same month,BRUTAL......
especially on type 4 dropping valve seats is a HUGE problem with the type 4 engine.
Power's in the heads, such a true statement.
Take any new aftermarket head and you will find poor valve seat transitions and rough casting marks.
Just taking a dremel and smoothing off all those edges with sanding rolls makes a difference.
They also skip a proper 3 angle valve job like the original heads, it's all lost flow and power.
Thanks for sharing Mike, head porting is such an important part of engine building that is frequently overlooked IMO.
Always so many things to still learn.
so true those single port exhaust are so restricted. I am anxious to see how they will run. with a decent cam
Thanks for sharing your knowledge man! This is some good info!
Thank you for sharing your knowledge
Heads are honestly the way to more power!
Good idea with the ridges in the upper intake. Don't know if they still make them but years ago a company made screens. It was usually a 1 inch spacer plate under the carb, then the screen between the plate and the intake. Was to help ATOMIZE the the fuel for better air/fuel mixture.
So the ridges you added will help the fuel ( splash ) in a sense. Causing it break into smaller droplets. Excellent idea.
I think I see where you’re going with this Mike. This should be a good primer for the VW engine builder novice / low buck builder.
Maybe a single port dual relief, doghouse cooled single carb with vacuum advance and maybe a pertronix? I’m looking forward to it.
total build budget so far 100 bucks. DOnt have a spare dog house so I am using stand up. but it will work. cant wait to fire it monday. should run super strong for a single. We do have some dual port heads but carb supply is dwindling. I will upgrade it from only swap meet finds. to show it can be done.
That doghouse would definitely be a future swap meet upgrade, and I’d love to see you push the performance limits of single port heads.
By the way , the name “Poverty Special” is the way to go!
Hi Mike and all you fellow watchers.
I admit to having different preferences and ideas. See, I don't fancy high displacement and powerful engines. I was looking very hard for a 1300 dual port engine (AB engine code) and finally found one. The heads on those have small valves which again is where I'm weird, coz I like that. I would love to build on that base and go with a 74 mm counterweighted crank, an Engle 100 cam, stock 77mm cylinders and pistons, 34 pict carburator and stock exhaust. This will make it possible for me to avoid having to spend money on machine work, which is extremely expensive over here AND it will give me that small displacement engine, but tuned and hopefully a little more agile than the stock engines. I want to attempt some porting to those 1300 dual port heads. I should be able to do the porting as well as the mild clearensing neccesary for the 74 mm crank myself, using hand-held air- tools, shouldn't I?
Will follow the budget build with great interest. Best Regards Lars Karlsson
you could do that if the case is in good shape Like no line bore needed. the 74 is almost a drop in with clearanced rods. just a little dremel. We will be doing one pretty soon if the case I took into the machine shop makes it.
Web 86 is better then the 100 engle. and if you want more power after you can ad ratio rockers.
Try putting little round divots all over like a golf ball I have heard it helps immensely with Flo.
Back in early 80s when 40X35 Autolineas were 37.50 , I worked on a Seat and guide Machine . And with it I could have done most anything. Knock out the guide and spread the valves apart by putting a fatter guide and larger seat. But We did not mess with VWs. The Opel club had us to do 11 motors that had the works on them.
wow looking at mills right now lets see maybe plus we are. Always wanted a valve grinding machine too. lets see if the old craigslist will deliver. ha ha.
@@Mikefngarage Do not kick me. I could have got Auto Machine shop but i told my old boss that times had changed.Most guys want a crate motor. Joe had alot of VW shit. Had a line bore box with a extra set of cutters that was still in their wrappers.
SP all day baby!!...lol... meaning that I should have saved up more for dual port..hahaha. Are miss match heads (part numbers) critical? I know its probably a dumb question.
single port not usually but there are some with different combustion chambers and valves gotta be the same there at least. for the budget ride.
I'm curious if you think a mild port job, like you show in the video, would make any difference for a factory fuel injected, 1600, dual port in a '78 Beetle convertible. At some point I will be rebuilding the engine, and from what I've read, there isn't much I can do to squeeze more horse power out of it if I keep the fuel injection (which currently works great, and I love).
In my Type3 with efi, a mild port did great initially. I ended up increasing CC's so that also made a larger amount of uhmph.
Not sure who told you that but they were filling your cup with bull crap. Get some displacement a cam and a mild port job and the fuel injection will work even better than stock.
why would you want a venturi in your intake?
on the single port the intake is almost maxed out. cant venturi but I opened up some areas. not much and got the air to flow around the valve better.
Is it possible to port 1200cc heads?
yea a little. and it can help. the corner on the exhaust is pretty tight. Not going to give you much power though. Porting mostly helps with higher RPM and those 40s are torque low RPM. too many RPM in there and you better check the oil pump size. Stock was a 17mm which is barely enough oil supply for 4000 RPM. 1600 rockers are a good upgrade but remember there are no cam bearings in there. If there are (upgraded at some point) you could put 1.25 rockers on it possibly. but rotate and check and make sure the springs dont bottom out. on the 1200 I run stock exhaust too. maintains the torque best.
@@Mikefngarage Thanks for the golden advice! I’ve got a 110 cam with cam bearings and upgraded the engine with a big bore kit to nearly 1400cc. I always keep the oil level high since I once ran it too low from a leak and ended up snapping the crankshaft. This engine is an experiment, so I really put it through its paces-daily driving, off-roading, etc., in my Baja Bug. On the freeway, I can hit 82 mph with some wind-breaking help from other cars, but usually cruise at 65 mph. Exactly like you said, I found that an independent dual exhaust hurt my torque, so I went back to the stockish exhaust. Just trying to figure out what else I can do to it. Currently I'm trying to design an adapter for a 34pict carb. I have the one that goes the other way around (adapting a smaller carburetor to bigger manifold) but you can't just flip it, I tried. so I guess I'll try to port the exhaust see what happens. Thank you!
@@barrioscorona215 100 cam would work better. 26mm pump on there. bore the oil intake a bit too. But if you power it up too much the crankshaft will break again.
@@Mikefngarage thank you for the info I will do that next. Thank you!
I have a question. I have a 1776 with mofoco 40/35.5 heads Engle 110 cam, dual dellorto dcnf carbs. Would adding D ports improve performance???