engine and drivetrain Getting started on Rebuilding DCOE 40's-What size Needle Valves?

[Hans]

Have you determined that the horns/air cleaner will clear the booster?

I too would not do the machining, mainly because if it doesn't work, you now need to start over and find a new venturi. You can sell the horns and get some bolt-ons.

[2002Scoob]

The horns should clear the BB fine, I've got Ti manifolds right now, but I'm debating swapping em out for the Ireland Engineering manifold instead, so as to give me more room for making the air box. 

 

I think the Lathing will be fun, and I work with a team of other talented machinists and engineers to drink beer over my shoulder  

 

I'm more than happy to take a good "told ya so" if I get it wrong, thou!

[2002Scoob]

Another question... Accelerator pump jets are 35's at the moment, gut, oder, nicht gut?

[2002Scoob]

In other news, I think the guy before me who owned these was rally racing steamed and ended up in the weeds a few times. lots of dust/grime/grass when I steamed/ washed/ and aired out the passages with the compressor this afternoon.

[downhillwolf]

Well depends on engine and length of pump rods also pump valve jet.
I have long pump rod with pump jet 40 and pump ex. valve jet 60. If you have 35 and 50 pump ex. jet valve this is almost similar... Pump jet is probably the last thing you should worry about, main concern is idle and main stack... Pump you need only when you pust the trottle fast enough, if you push it really slow all the gasoline from pump will go through pump ex. valve.

If you are from Germany why don't you use aluminium bolt on velocity stacks from VergaserWerkstatt? you will not need to machine ventury.

 

[2002Scoob]

If you are from Germany why don't you use aluminium bolt on velocity stacks from VergaserWerkstatt? you will not need to machine ventury.

 

Well, I'm actually from California, but have been living in Germany for the last 2.5 years. Which is why I love this site for it's english language know-how.

 

And, to answer your question, it's because i'm an industrious fellow who loves making things more difficult/complicated than they have to be for the sake of the challenge and the experience And, i've already purchased these trumpets, so I'm stuck with em', haha.

[downhillwolf]

Well buddy, then you went down the right road with webers, because they are the most difficult thing that you can get on a m10 engine

[Stevenola]

Like downhillwolf says, the accel jets are down on the priority list, but they do contribute to the mixture at higher rpm's as the vacuum will pull fuel out of them even when not used for acceleration.  But thats a final tuning thing.

 

I'd also sell the slide in trumpets and get the bolt ons, you'll have bigger issues to deal with coming up, don't waste time grinding away a factory part but have at it if you must.

 

Try to consider the priorities the FAQ has suggested: AFR gauge, dcoe e tubes, final air filter set up installed, then tune for WOT, idle, and transition, then smallest accel pump that won't pop or go lean or rich on accel.  Adjust jets/bleeds accordingly with drills to minimize expense.

 

This process will be exhausting enough you'll be glad you didn't mess with lathing out the aux ventuis and creating more work or possbly f'ng them up. My $.02

 

Also in my old dcoe32's I threaded and plugged up the cold start tubes with a 6mm hex grub screw in each barrel, the mechanism is not needed for any cold starts and this stopped any potential fuel/air leak. Then I put a gasket between the body and plate.

 

Another question... Accelerator pump jets are 35's at the moment, gut, oder, nicht gut?

Edited February 4, 2016 by Stevenola

[2002Scoob]

Also in my old dcoe32's I threaded and plugged up the cold start tubes with a 6mm hex grub screw in each barrel, the mechanism is not needed for any cold starts and this stopped any potential fuel/air leak. Then I put a gasket between the body and plate.

 

this was actually going to be my next question. The car sees some cold days here in Germany, but I wasn't sure about how to rigg up the choke mechanism. There are "cold start delete kits" out there

 

http://www.dellorto.co.uk/shop/weber-carburettors-parts/carburettor-parts-weber-carburettors-parts/dcoe-dcosp-parts/dcoe-cold-start-device-elimination-kit/

 

http://www.dellorto.co.uk/shop/weber-carburettors-parts/carburettor-parts-weber-carburettors-parts/idf-parts/weber-choke-blanking-plate/

[downhillwolf]

Well cold start is good if you use car for everyday use. I use mine just for sunny days with temperatures higher than 15°C.

There are ways to delete this mechanism:
-Use blockoff plate and everything(pistons) in place

-use the expensiver kit to change everything that has something with cold start(jets...) but dont' know why the pump rod is there in set also?
-drill M6 thread in cold start canal and seal it with M6 screw

I did this: drill M6 thread and fill it with cold welding mass (some kind of polymer/composite for aluminium), made a block off plate from stainless steel and used a gasket to prevent gasoline leak through cold start holes...
If you want to have a stainless steel instead of yellow plated steel I have a few more of those plates, they look like this

[2002Scoob]

I just found this guy's writeup this morning, which is pretty helpful in a lot of ways, and he talks about the redundancy of the pump-mechanism. 

 

http://www.bmw2002faq.com/topic/80955-dcoe-installation-faq/

 

My car is also a "fair weather" car, but I don't mind driving it on those occasional nice winter days into work or the mountains where it can be significantly colder, or on vacation trips where it can be downright freezing at night but fair in the days. 

 

I'm also confused about that kit, in that it includes so much other stuff... I wish they just supplied the hardware parts as I've got to rebuild everything else and I don't need a bajillion top cover gaskets. 

[downhillwolf]

Well top cover gaskets are really thing you should have on your shelf in case you need it.
Cold start mechanism is only for starting and if you have a car in warm garage(15°C) you dont need it. But if you have car outside is advised to use this since tapping the throttle for a long time would not be good
Even when weather is warm 20-30°C you stil need to make one throttle pump before turning the ignition key and when it starts a few tapps on the throttle to squirt more fuel from carburetor pump to run engine well from cold state.

 

One thing that you must be careful about using webers on winter days... beware of freezing air nozzles. Cold weather 3°C and under may cause freezing air jets with moisture from air. That is why 2002ti used snorkels on airbox to suck warm air from engine compartment to keep carburetors warm to make this issue gone. So cold air intake for winter day is a no go...
I know one Alpina car for rally with big filters and every other hole was sealed for winter rally only radiator opening from front was kept open and car was instantly pushed to it's limit so radiator was hot and hot air would come to airbox.

Edited February 4, 2016 by downhillwolf

[2002Scoob]

Sooo, this is the Intake I WANT.... but, I've been searching for anything regarding it and have found nothing.

 

If anyone knows who makes it, or where to get it, let me know...

 

Otherwise, I'm going to make my own version instead.

 

[downhillwolf]

I think this is custom made because it has a hole for brake booser... Beware too much wight on the end of carburetors may cause manifolds to break...

[Simeon]

That looks like an air box lid off ??? car with a custom base plate for the carbs and a pod filter.

Take some dimensions and get down the pick-and-pull.

I have been thinking about one of these (for the side drafts I have not fitted yet) with a short pipe and pod filter mounted above the battery.

http://www.racetep.com/twmab.html

Edited February 4, 2016 by Simeon