# Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin ignition

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#### Abraham Leket

##### Well-Known Member
Carb location : From reviewing GP catalog it seems that the updraft installation is most common. Intuitively- when hand pop the engine- the down draft can supply mixture better due to gravity . The Flywheel type on front and the lack of starter leaves plenty of room for downdraft manifold.

Ignition- in a no electric engine and hand pop- can Slick 4316 and Vertex mag (in the 009 drive) without advance can work together as reliable twin ignition system?

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#### Pops

##### Well-Known Member
HBA Supporter
Log Member
Re: Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin igniti

IF you are using a flywheel end of the engine to drive the prop, how are you going to drive the Slick 4316 mag? No one makes a mag drive for the pulley end of the engine and the 4316 will no work on that end of the engine because of the mag would be turning the wrong direction. Have to use a different mag. I have been making parts for a mag drive for the pulley end of the engine for the flywheel drive engine that I am putting together. Mag on pulley end and a 009 dist of the second ignition. I have my extra set of single port heads drilled of the 10 mm lower plugs.

#### Abraham Leket

##### Well-Known Member
Re: Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin igniti

Pop thanks- this setup- no electricity -only works on direct drive type-that is a very good point and I had no idea about mag direction.
Will the direct drive work on the hand start 4316 and vertex (on 009 drive pin)?in your setup- 009 without advance? or you will use 009 with 12 degrees advance? I guess you will have to start it with 4316 and then- turn on the 009 (after the engine turns at good RPM).
As for carb positioning- any comments?

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#### Pops

##### Well-Known Member
HBA Supporter
Log Member
Re: Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin igniti

Pop thanks- this setup- no electricity -only works on direct drive type-that is a very good point and I had no idea about mag direction.
Will the direct drive work on the hand start 4316 and vertex (on 009 drive pin)?in your setup- 009 without advance? or you will use 009 with 12 degrees advance? I guess you will have to start it with 4316 and then- turn on the 009 (after the engine turns at good RPM).
As for carb positioning- any comments?
The 009 distributor has centrifugal advance with weighs and springs. You can get different springs and with a little work set the advance to the same as the 4316 mag ( 25 degs).
If you are using the prop on the flywheel end of the VW engine, where are you going to put the Slick 4316 mag? I don't understand how you are going to use the Slick 4316 mag. BTW-- The Vertex mag that plugs in the distributor hole in the case is big and heavy. Friend of mine used one in is VW engine and after about 100 hrs the bearing were wore out.

Dan

#### Abraham Leket

##### Well-Known Member
Re: Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin igniti

Thanks Dan- I'm beginning to get the setting :First- for a hand start I need to have a direct drive type 1.
As for twin ignition( in hand starting)-I need to have an electric system i.e- 4316 with either 009 or electronic one as secondary (and they need power to run). I can now see why so few setups have Vertex Mags up front- its the weight and its implication on bearings life not to mention $1200 cost. But then-if I already need to have an electric system I might as well drop the hand start issue and get a starter and if I go for electric start- I can go back to my original choice-the flywheel setting -but now with 009+electronic as secondary. Interesting choice. Question on 009- I've seen some fancy distributors in Summit and Chirco-all promise mega spark. Any comment on them? As for carb location- any suggestions on updraft or downdraft settings? (oil cooler is not on top). Thanks! Last edited: #### Pops ##### Well-Known Member HBA Supporter Log Member Re: Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin igniti Thanks Dan- I'm beginning to get the setting :First- for a hand start I need to have a direct drive type 1. As for twin ignition( in hand starting)-I need to have an electric system i.e- 4316 with either 009 or electronic one as secondary (and they need power to run). I can now see why so few setups have Vertex Mags up front- its the weight and its implication on bearings life not to mention$1200 cost.
But then-if I already need to have an electric system I might as well drop the hand start issue and get a starter and if I go for electric start- I can go back to my original choice-the flywheel setting -but now with 009+electronic as secondary. Interesting choice.
Question on 009- I've seen some fancy distributors in Summit and Chirco-all promise mega spark. Any comment on them?
As for carb location- any suggestions on updraft or downdraft settings? (oil cooler is not on top).
Thanks!
I have never used a carb on top of the engine. I keep thinking about a stuck float valve in the carb. I had a 1966 VW auto catch on fire going down the highway one time for that reason. Doesn't take much, just a small piece of something to stop of the seat and stopping the nettle from seating.
I have been looking at this. Compu-Tronix. Electronic Ignition Systems
I don't know anything about how good it is.
You are right, interesting choices.

Added --- My wife's mothers family were Orthodox Jews that came to the U.S. from Germany just before WW-1. All the males wore side locks, ( Peyot).
All of my children and Grand Children would feel at home in Israel. So would I . Would like to visit someday.

Dan

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#### Abraham Leket

##### Well-Known Member
Re: Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin igniti

Dan!
Gods will- you will make it to Jerusalem and you might even do a Bar-Mitzva to one of the grandsons in the Western Wall!
Thanks for your advise- I will need much more once the engine will arrive- Mid 2016. Untill then-
Shalom from IsraeI !

#### Pops

##### Well-Known Member
HBA Supporter
Log Member
Re: Updraft Vs downdraft carb style on a flywheel hand pop type 1835 and twin igniti

Dan!
Gods will- you will make it to Jerusalem and you might even do a Bar-Mitzva to one of the grandsons in the Western Wall!
Thanks for your advise- I will need much more once the engine will arrive- Mid 2016. Untill then-
Shalom from IsraeI !
Someday.

Shalom from an American Cherokee