antoninosavoca

Hallo i am new member from Montesilvano, Italy,my name is Antonino Savoca,i am working to race a 928 S my.1980,someone can help me to find a carburetors conversion kit :
Thank you very much Antonino Savoca

Hilton

Check this thread..

https://rennlist.com/forums/928-forum/461087-hi-from-belgium.html

He's several steps ahead of you

bigmac

Good luck.

belgiumbarry

i have seen this only one on the 928M site....

http://www.928motorsports.com/ianraper.php

so he's using the horizontal DCOE Webers which gives him the advantage that everything "fits " under the bonnet.... i choose the vertical IDA Webers , so only my ITG air filters will be above bonnet height.

On the other hand Ian Raper needed a much more complicated inlet manifold , think custom made ?.... excisiting models you can see are for Chevy and Ford V8 applicatons... but with a good "inventive" aluminium TIG welder it must be possible to make such manifold.

My inlet manifolds are only 8 "simple" tubes ( conical ) and adapted flanges which you can laser nowadays very easy... weld and machine them flat. Every tube has a vacuum line take off ( 6 mm ) which run to a collector for the brake booster.

Oh, and i made them from stainless steel , which is a bad heat conductor, so to prevent the carbs from excessive engine heat... for aluminium ones there are heat shield plates , which you mount between as "gaskets"....

I did not make calculations yet on the pulse lenght of the system... just made the inlet manifolds high enough to clear the distributor ... and keeping all as low as possible.

PS will be soon on a dyno with results and pics !

Jim bailey - 928 International

Ah ...carburetors SUCK , the floats flop around in hard cornering and the car misfires runs out of gas as you try to exit the corner. Fuel injection even as primative as CIS is far superior for road racing. I ran a mechanical injected 911 and used a carbed engine as a "spare" I can still hear the bobble BUDDA BUDDA as the carbs ran out of gas in the corners.

Jim bailey - 928 International

Ah ...carburetors SUCK , the floats flop around in hard cornering and the car misfires runs out of gas as you try to exit the corner. Fuel injection even as primative as CIS is far superior for road racing. I ran a mechanical injected 911 and used a carbed engine as a "spare" I can still hear the bobble BUDDA BUDDA as the carbs ran out of gas in the corners.

Larry928GTS

Gosh Jim. Next you'll probably say my drum brake conversion isn't a good idea either.

Jim bailey - 928 International

I was just looking at some wire wheels ....

dr bob

I can remember how folks liked the peaky performance of carbs, mistaking the surging for "extra" power. Almost amy reasonable FI system will outperform carbs, even big-bore IDA's on custom manifolds with air cleaners poking through the hood. IDA's claim to fame has always been minimum pressure drop at WOT, OK for long straights but a challenge when you have part-throttle sections in between. Good news is that you can buy all sorts of chokes and venturis, primary and secondary, boosters, emulsion tubes and jets, and they are all pretty easy to change while tuning. Bad news is that you get to buy all sorts of chokes and venturis, etc if you want to tune them well. Compare with hooking up the laptop to the smarts and tuning from the keyboard. No comparison, in my opinion.

Yeah, the big Webers look cool, pretty amazing for a technology that was obsolete over 40 years ago now.

BPG_Austin

My first porsche was a 356B. Great machine, and for a brief time my only car. However, brings up memories of tearing carbs apart at 5 in the morning to fix and sync before going to work. NEVER AGAIN will I play with carbs. Give me fuel injection, please!

Andre Hedrick

Surely one could make gimbal float system, and more pressure on the fuel

Jim bailey - 928 International

The first 911s had float less carbs then later they fitted Webers. The one weber carbed 928 that I saw running and driving had a big problem with heat soak and boiling the fuel in the bowls. The customer always opened his hood when he stopped in for parts.

belgiumbarry

i work hole days on a computer... i scroll forums all nights on a computer.... so... pleaseeee... not on my racecar....

Jim bailey - 928 International

There is something to be said about an engine which will run on just one ignition power wire

belgiumbarry

i have the "hot setup" in my neighbour.... but expensive... i think. No, i want to try out the carbs... and see what we can do with it ...