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Re: Fitting two double carbs on 1.3 GT

Posted: Mon Apr 25, 2005 9:49 pm
by audi50
No Problem.......just close the 2 holes ( in Germany we call it " ABGASRÜCKFÜHRUNG" with 2 pcs. of aluminium bolts. You don't need them if you will fit the solex.

Also cut the Metal pie from the front exhaust. You need a rest of 4 cm to crimp it toogether and weld it. The system was mounted in every MK 1 from mid 1979 up to production end 1981.

You dont need to close them in the Sorg bridge. Some guys will srew plates over the holes, but the way with the bolds is better.

Mike

www.audi50.com
and webmaster
www.wl-motorsport.de

TheFog wrote:As I'm fitting two double carbs (Solex 40) on my '81. 1.3 (polo mk1), I encountered one problem....or doubt.
What should I do with this exhaust holes on cylinder head that lead exhaust gasses through inlet manifold and as I found out are used for heating inlet and prevent carbs icing: close those holes on head as well as on exhaust pipe or should I connect them like there were with some pipeing?
One guy told me that closing these channels on their exit from head will create rough vortex of exhaust gasses and bad work of that two cylinders and that I should weld them right behind exhaust valves inside cylinder head.
Please help! Thanks!
Here are some pictures to give a better view of what's bodering me:
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Posted: Mon Apr 25, 2005 9:56 pm
by D4V1D
just out of intrest.
what inlet manifold are you going to use?

Posted: Tue Apr 26, 2005 8:30 am
by audi50
We use the inlet manifold from VW Motorsport or Sorg Motorsport. You can get it at EBAY: The Sorg bridge ist the shorter one but the VOLKSWAGEN bridge ist better. So try to get one of these articles.

Mike
D4V1D wrote:just out of intrest.
what inlet manifold are you going to use?

Re: Fitting two double carbs on 1.3 GT

Posted: Thu Apr 28, 2005 11:49 am
by TheFog
Why bolts? wouldn' be simplier to put a plate over it and it would be effective also?
I'm making custom inlet and that plate would be in one piece with the rest of inlet.

I don't understand what you ment with this
audi50 wrote: Also cut the Metal pie from the front exhaust. You need a rest of 4 cm to crimp it toogether and weld it. The system was mounted in every MK 1 from mid 1979 up to production end 1981.
Perhaps you ment on this pipe that I should remove it and weld the hole???
Image

Thanks a lot, I was looking for someone who has really done this before! ;)
So, all those stories I heard about vortexing of exhaust gasses are nonsense? There will be no lack of performance and it's not neccesery to close these two exhaust channels at ther begining right after exhaust valves?

From your expirience can you tell me how much can be gained from 1.3gt engine with two double 40mm carbs? These Solex of mine are from Alfa Romeo 2.0 engine and I'm wondering will it be hard to tune 'em to this engine, changing injector perhaps, etc.?

Once again, thanks a lot!!!

Re: Fitting two double carbs on 1.3 GT

Posted: Thu May 05, 2005 7:21 am
by audi50
Yes, this q m. hose should be cut an welded. MY tuner ist producing 1300 ccm engines HH and GK for Slalom hill race and so on. Thew maximum you can get out of a HH Motor is really 135 with 45 mm Solex or Weber and 145 with 45 mm Solex or Weber. With racing ignition and Golf ABU head you'll get 160 PS.....maximum made head, camshaft, crankshaft, springs and more.

You will get without changes - just putting on the Solex- 85 PS if you take the GK engine or 70 PS if you take the HH engine.

Regarding head: Close the holes, we'll do the job daily at my tuner.

MIke

TheFog wrote:Why bolts? wouldn' be simplier to put a plate over it and it would be effective also?
I'm making custom inlet and that plate would be in one piece with the rest of inlet.

I don't understand what you ment with this
audi50 wrote: Also cut the Metal pie from the front exhaust. You need a rest of 4 cm to crimp it toogether and weld it. The system was mounted in every MK 1 from mid 1979 up to production end 1981.
Perhaps you ment on this pipe that I should remove it and weld the hole???
Image

Thanks a lot, I was looking for someone who has really done this before! ;)
So, all those stories I heard about vortexing of exhaust gasses are nonsense? There will be no lack of performance and it's not neccesery to close these two exhaust channels at ther begining right after exhaust valves?

From your expirience can you tell me how much can be gained from 1.3gt engine with two double 40mm carbs? These Solex of mine are from Alfa Romeo 2.0 engine and I'm wondering will it be hard to tune 'em to this engine, changing injector perhaps, etc.?

Once again, thanks a lot!!!

Posted: Thu May 05, 2005 1:36 pm
by TheFog
audi50> thanks a lot, I'm sincerly gratefull, but would like to ask you a few more questions (if it's more convinient to you, we can continue by e-mail although I send you an e-mail regarding this about a month ago at your e-mail adress that is on www.audi50.de but you didn't answer)

I would like to know is it possible to leave the fuel pump I have now (it's not stock pump, it's from some old porsche but probably similar performance)? If not, from which car could I use its' fuel pump?

Also I heard that is neccesery to move ignition "in advance"? is that right? Should there be any major difficulties with getting this engine running with this solex 40mm?

My engine is 44 kW/ 60 PS (that's HH if I'm not wrong) but with some exceptions: lowered head, polished channels in head, a bit work considering valves, and......block is from an engine that drove Berg cup (wider cylinders and pistons than in original 1.3 GT), so I guess I could count at about 75-80 PS.

And last thing for now: do you perhaps have some pictueres (as more detailed as possible) of inlet manifolds that you use (Sorg, VWM, etc.) and if it's not a problem to say a few words why is the one from VWM better as you said, how long (or better to say, short) should it be, etc.

Once again, thanks!
Greetings!