A V8 Maybe
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Dave Sohlstrom
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It must mean I have the disease also. 2 lathes, 2 vert mills 1 with CNC, 1 horz mill, 1 shaper, 1 surface grinder 1 mini CNC router plus a complete wood shop.
Dave
Dave
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Hi Guys
I only had one job on this morning and so on the way back home I dropped into the local mini bike shop and was able to score a box of old mini bike heads and pistons for my foundry.
After that little success I had a play with the sump and made it fit the new Big end Caps.
Pete
I only had one job on this morning and so on the way back home I dropped into the local mini bike shop and was able to score a box of old mini bike heads and pistons for my foundry.
After that little success I had a play with the sump and made it fit the new Big end Caps.
Pete
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Hi Pete,
I see in your assembly picture you have 2 diaphragm type carburetors sitting there. I know that some of our fellows on the West coast have used them but I haven't had much luck with them. They take some internal modifications and are very touchy to adjust. I might suggest something a little simpler for fuel delivery. You can even make it look prototypical if you so choose. This is the one I made for my 302. It's basically and air bleed type carb that's been prettied up to look like the original full sized carb.
I see in your assembly picture you have 2 diaphragm type carburetors sitting there. I know that some of our fellows on the West coast have used them but I haven't had much luck with them. They take some internal modifications and are very touchy to adjust. I might suggest something a little simpler for fuel delivery. You can even make it look prototypical if you so choose. This is the one I made for my 302. It's basically and air bleed type carb that's been prettied up to look like the original full sized carb.
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Hi George
That Carby looks wonderful, I did not know the wipper snipper ones needed modifying and it sounds like I should rethink it.
Now that you mention it, I remember reading somewhere they needed the fuel tank under pressure to run as well.:wall:
How does twin strombergs sound?Thm:
While im gone I want to think about a couple of things including some form of taper lock for the flywheel. Its been on my to do list for a while, I just dont like the idea of using a grub screw on a Crank that takes so long to make.
If worst comes to worst, I guess I can melt my little collection of carbys, ive got about a dozen now, maybe not enougth metal for the valley cover in them but its a start ;D
Pete
That Carby looks wonderful, I did not know the wipper snipper ones needed modifying and it sounds like I should rethink it.
Now that you mention it, I remember reading somewhere they needed the fuel tank under pressure to run as well.:wall:
How does twin strombergs sound?Thm:
While im gone I want to think about a couple of things including some form of taper lock for the flywheel. Its been on my to do list for a while, I just dont like the idea of using a grub screw on a Crank that takes so long to make.
If worst comes to worst, I guess I can melt my little collection of carbys, ive got about a dozen now, maybe not enougth metal for the valley cover in them but its a start ;D
Pete
canadianhorsepower
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Hi you dont need to pressureise the tank if you gas tank is higher than your carb. But you will have to remove the pump gasket from the carb
as for them beeing hard to adjust.. a simple fix is to drill the throtle plate with a .040 drill. nice work enjoy your holiday
as for them beeing hard to adjust.. a simple fix is to drill the throtle plate with a .040 drill. nice work enjoy your holiday
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Hi Guys
Merry christmas.
I made it home this morning after another sleepless overnighter, first thing I did of course was to open up the shed to greet some old friends.
In order to get this build back on track I started on the patern for the Valley cover but will have to do some more work on the heads to locate the inlets and water jackets as well as bolt on a subplate under the manifold.
With any luck ill get the Valley cover Cast up this week.
Hay Andy
Did you get your new mill?
Hi Canadianhorsepower
Would you please give some more detail on the Carbs?
I dont know if ill end up using them now or not, but would love it, if you were able to shed some more light on what to me is totaly unexplored ground.
for instance you mention the removel of the pump gasket?
Pete
Merry christmas.
I made it home this morning after another sleepless overnighter, first thing I did of course was to open up the shed to greet some old friends.
In order to get this build back on track I started on the patern for the Valley cover but will have to do some more work on the heads to locate the inlets and water jackets as well as bolt on a subplate under the manifold.
With any luck ill get the Valley cover Cast up this week.
Hay Andy
Did you get your new mill?
Hi Canadianhorsepower
Would you please give some more detail on the Carbs?
I dont know if ill end up using them now or not, but would love it, if you were able to shed some more light on what to me is totaly unexplored ground.
for instance you mention the removel of the pump gasket?
Pete
Motormagican
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Hello Pete,
Hope you had a great Holiday. Looking good with your project.
Hope you had a great Holiday. Looking good with your project.
trumpy81
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Welcome home Pete! I hope your holiday was a good one 
Yes I bought my new mill, but it's not the one I told you about. Long story, but I ended up buying a Titan TM45FG. It should arrive mid-January. Then I just need some pointers on setting up a casting foundry and I'll be all set to build one of these V8's ... so hurry up and get it finished ... lol
Yes I bought my new mill, but it's not the one I told you about. Long story, but I ended up buying a Titan TM45FG. It should arrive mid-January. Then I just need some pointers on setting up a casting foundry and I'll be all set to build one of these V8's ... so hurry up and get it finished ... lol
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Hi Pete,
Here's what I know about 2 cycle carbs. There are 2 different internal setups used, one for a gravity fuel supply and one for a lower type. There is a diaphragm/gasket under the upper cover, not the side with the chrome cover. For the engines that have to draw fuel from a lower level this diaphragm is activated by a pulse from the crankcase via a port that comes through the carb flange. Sometimes there is a primer bulb on this side of the carb to prime it. The other side of the carb that has the chrome cover held with 4 screws covers another diaphragm. This one had the metal plate riveted in the center. The metal plate has a small boss that pushes on the lever that activates the flow control needle valve. The way it works is when there is a vacuum signal through the venturi it pulls this diaphragm inward which then opens the flow needle.
For model engine use the first thing that needs to be done is to make a venturi reducer as even the smallest of these carbs is too big for smaller engines. The next thing is the needle valves, idle and high speed, need to be modified as they are to coarse for fine adjustments.
Several fellows use different methods for fuel feed. One fellow made an air pump and hid it inside the alternator to provide pulses for the carb. Another fellow uses very low pressure electric fuel pumps to supply the carb and the last fellow has a little hand pump that pressurizes the fuel tank to get fuel to the carb. The carb won't flood because the fuel needle valve won't open until there is a vacuum signal.
I tried several methods to utilize these carbs and didn't have much luck.
If you look at the video of my 302 engine running you will see that I have a small air bleed type carb on it. After years of fooling with carbs I ended up with this type. Once I had the carb adjusted to my engine I then made a replica of the carb that came on the full sized engines and put all the air bleed components into it. I don't have it mounted on the engine because it gets buried under the air filter so when people wanted to see it I would have to pull the air filter every time. Now I just set it out with my display.but it does run as well as the one that's on the engine.
When Steve Huck built his V-8 he used a similar internal design and made the outside look somewhat like a full sized carb.
I don't have complete drawing for my carb as I had one to copy when I was building mine. I do have sketches for the internal air bleed passages and venturi shape. I will dig them out for you at first chance.
Here is a video link to my 302 running. This was taken by a fellow at a local antique engine show a couple of years back.
[ame]http://youtu.be/fRVYYtdhG_8[/ame]
gbritnell
Here's what I know about 2 cycle carbs. There are 2 different internal setups used, one for a gravity fuel supply and one for a lower type. There is a diaphragm/gasket under the upper cover, not the side with the chrome cover. For the engines that have to draw fuel from a lower level this diaphragm is activated by a pulse from the crankcase via a port that comes through the carb flange. Sometimes there is a primer bulb on this side of the carb to prime it. The other side of the carb that has the chrome cover held with 4 screws covers another diaphragm. This one had the metal plate riveted in the center. The metal plate has a small boss that pushes on the lever that activates the flow control needle valve. The way it works is when there is a vacuum signal through the venturi it pulls this diaphragm inward which then opens the flow needle.
For model engine use the first thing that needs to be done is to make a venturi reducer as even the smallest of these carbs is too big for smaller engines. The next thing is the needle valves, idle and high speed, need to be modified as they are to coarse for fine adjustments.
Several fellows use different methods for fuel feed. One fellow made an air pump and hid it inside the alternator to provide pulses for the carb. Another fellow uses very low pressure electric fuel pumps to supply the carb and the last fellow has a little hand pump that pressurizes the fuel tank to get fuel to the carb. The carb won't flood because the fuel needle valve won't open until there is a vacuum signal.
I tried several methods to utilize these carbs and didn't have much luck.
If you look at the video of my 302 engine running you will see that I have a small air bleed type carb on it. After years of fooling with carbs I ended up with this type. Once I had the carb adjusted to my engine I then made a replica of the carb that came on the full sized engines and put all the air bleed components into it. I don't have it mounted on the engine because it gets buried under the air filter so when people wanted to see it I would have to pull the air filter every time. Now I just set it out with my display.but it does run as well as the one that's on the engine.
When Steve Huck built his V-8 he used a similar internal design and made the outside look somewhat like a full sized carb.
I don't have complete drawing for my carb as I had one to copy when I was building mine. I do have sketches for the internal air bleed passages and venturi shape. I will dig them out for you at first chance.
Here is a video link to my 302 running. This was taken by a fellow at a local antique engine show a couple of years back.
[ame]http://youtu.be/fRVYYtdhG_8[/ame]
gbritnell
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HI Danny
Thanks for that Mate, but im sure glad to be home
I was going to put up another pic of the progress with the valley cover but am having connection problems on the computer I normaly use and this one is not allowing me to log on to photobucket :wall:
That Mill is pretty much the same as mine Andy, so should do the job no worries
As you know, Im not an expert by any means and have only done half a dozen pours so far but am starting to get an idea on the simple paterns.
Im planing to pour the Valley cover on Sunday if you would like to join me? I Watched Bez do a few pours before I jumped in with the V8 Block;D
Hi Vince
Im absolutly exhausted Mate, but this thing just will not build itself
Hi George
I have watched that Video meny times and love it all the more every time.
I am very interested in how you made what seems to be the accelerator pump and would be very much in your debt if You were able to find any details or photos that you have about your Carby and if I could push my luck a bit, the Distributor, I have no details or plans for a dizzy at all yet.
An ignition system has not even been contemplated so it would be great to see how you acheaved such a great result ;D
Pete
Thanks for that Mate, but im sure glad to be home
I was going to put up another pic of the progress with the valley cover but am having connection problems on the computer I normaly use and this one is not allowing me to log on to photobucket :wall:
That Mill is pretty much the same as mine Andy, so should do the job no worries
As you know, Im not an expert by any means and have only done half a dozen pours so far but am starting to get an idea on the simple paterns.
Im planing to pour the Valley cover on Sunday if you would like to join me? I Watched Bez do a few pours before I jumped in with the V8 Block;D
Hi Vince
Im absolutly exhausted Mate, but this thing just will not build itself
Hi George
I have watched that Video meny times and love it all the more every time.
I am very interested in how you made what seems to be the accelerator pump and would be very much in your debt if You were able to find any details or photos that you have about your Carby and if I could push my luck a bit, the Distributor, I have no details or plans for a dizzy at all yet.
An ignition system has not even been contemplated so it would be great to see how you acheaved such a great result ;D
Pete
