rebuilding a set of twins doce 40

[opeldean]

i am getting started.

[Killer Texas GT]

I evedently have a racing set of 45 Webers wihich do not have a port for the vacum advance on the back side of the mounting plate. Currently I am runing retard and advance off of the intake which is clyinder balanced, how or where do I tapp in for the advance diaphram vacum on the 45 DOHC? Also need to locate a idle jet kit as I am jetted to big and need to drop down a couple of sizes.
rk

[opeldean]

i cleaned up my floats while my 1st carb sits in cleaner. i used 50 micron sand to clean it, We have a 50 micro abrader at work that i used on the lunch hour.

[nobody]

Killer Texas GT, as far as I have seen none of the OE types had vacuum ports. So you get into choosing distributors for your needs based on mechanical advance. For the advance to wark correctly it needs to be a metered port with several bleed holes along the butterfly openings. Only the DCOM has this on them that I'm aware of. As for jets and stuff if you can wait 2 weeks for a bargain I'd Email Gabriele and ask for what you want and be prepared for very low pricing.

italian.carburetors@tiscali.it

Dean I have a set of OMs when you get done with those. Looking good so far.

[opeldean]

I May Have Damaged The Butterfly ...1 Side Doesnt Close In The Shut Position, I May Have Torqued It And Bent It When I Was Removing The Nut On The End Of The Throttle Linkage..there Is An Air Gap Of 2 Layers Of Paper Around The Bottom Of The Brass Circle..this Is Enough To Open One Of The Transition Holes Part Way In The Closed Position..its Not Much..


How To Fix? Bend It Or New Part?..does It Matter?

[baz]

can you take the butterfly out
if so you will be able to see how flat it is (use a piece of glass and a little ink then look from underneath if its bent you will have a deeper colour where its bent)
you nay be able to flaten it ok that way
or you will see if its the spindle

[opeldean]

i took the brass colored disk out of the shaft, it is bent when layed on glass.

i am looking for something to flatten it against..like an anvil.

you were right on again Baz

thank you

[madhatterpdc]

Sounds like you are on the right track, it can only be a twisted throttle shaft or a tweaked butterfly valve. Both items can be replaced, but I get the impression that lining them up proper is quite a process. You might be able to save a little trouble by etching a light line where the shafts lie on the valve.

[baz]

try an old hub or disc any thing heavy thats been machined and use some thing flat and 1/2 inch or more thick to put on the butterfly disc before you hit it gently
repeat on glass to test
repeat till flat
and when bob ,otto and all the engineers stop crying with laughter and start typing do thi only as a last resort
you are better off to replace the butterfly

[nobody]

Gabriele sells them for something like 3.50 new with screws.

[opeldean]

i tried to straighten the brass disk,no luck, i will order one for gabriele..no problem.

i had a small transition jet that would not unclogg,the hole is so small a pin wont go thru it, carb cleaner would not dissolve it.

the scunci steamer has quite a bit of PRESSURE and a lot of heat...it unclogged it, i went of all my jet this way, i also used it to de-oil by brass cover screws before clear coat.

unlike air, you can SEE steam travel thru the holes.as a visual aid

i have listed the scunci steamer in the products/accessories section

[MICAH1]

You're the man Bucky...... Your pictures and video's take us on this site to school.

[opeldean]

does anyone have the article written by Gil on installing side drafts in an opel?

there is a drawing on the needed adapter i believe i need , to move the thermostat housing up and out of the way of the irmscher intake manifold.

Gil said he would mail it to me today..but that could take a while.

Gil said, the front irmscher intake wont fit w/o adaptation.he said i need to find an irmscher adapter with the long bolts.

has anyone here every made one?

[RallyBob]

The short Irmscher intakes originally came with a complete new lower thermostat housing. It is substantially offset compared to stock. I've never seen an adapter to use the stock housing, but I imagine one could be built with enough time/patience.

[nobody]

I was thinking something like this might work.

[ConreroGT]

you mean something like this:

[opeldean]

i am not sure what your picture is or exactly what i need.I will need to dive into it pretty soon and see what the problem is.

[nobody]

I'll get it welded up and post another pic of it offset about an inch forward.

[ConreroGT]

The piece shown is the "adapter" in the foreground that bolts between the stock thermostat housing and head...what it does is it offsets the housing forward so it is out of the way of the intake manifolds. This will enable you to move the temp sending unit out of the way. The drawing Gil is sending you is probably the adapter that is pictured.

I am willing to sell it if it ends up to be what you need.

~kyle

[nobody]

You wouldn't happen to know how thick it is and how far it moves it forward would you?

[RallyBob]

If you'd like, tomorrow I can dig out an Irmscher thermostat housing and take a few pics to show the differences compared to a stock one.

[nobody]

That would be very helpful. thanks

[ConreroGT]

I could measure, but off the top of my head I recall it to be about 1/2" thick or so and will offset fwd about 3/4"...just a rough estimate more or less. It's in a garage off site of my apartment right now. So I don't have immediate access to it.


You can sorta tell from the photo.

The far hole on the right is the bolt hole for the head. The hole just to the left of that is where the stat housing would attach.

Then if you look on the far left of the adapter, the bolt hole on the far left is for the other side of the stat housing and the one just to the right of that is the bolt hole for the head. Make sense? So you can kinda guess how far it'll move it.


~kyle

[opeldean]

question 1- do you think my pump jets are oriented correctly- they only go in one way..but is perpendicualr to flow.

question and answer 2- jet holes are small, i was shown this as a double check after you have cleaned and dried them, you can feel air flow on your lip.

statement 1- my engine gets dirtier by the day, but my carb is clean enough to use as a candy dish..no chips as a single salt grain would ruin the whole thing

i am waiting on parts from italy- dam they are cheap $9 for a rebuild kit including needle valve,shipping was about 5 or 6 bucks, but i bought some other stuff..when it came to a lost bushing,bearing,and a bolt..Mr Gabriele thru it in for free..when have you ever got that?he is among the best vendors,answers his email too.
thanks to you all at opelgt.com ..its going well
special thanks to dave "nobody" for primary help in the chat room

[opeldean]

as i disasembled my carb i have listed the jets,they are quite diifferent from the german reference as in prior post

I have ordered 190 airs for the main jets form italy.

it is believed the background of these carbs are that this jetting was installed with irmshler shortis on a gt in the 80's by irmshler...thats the
info on the history. gt was a rebuilt cih2 liter