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Pictures of all these different setups would be great 馃憤

(I always thought the reason to ditch the TS plenum/throttle body was based on space in GT/Spider)
 
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I race a 1750 with a 2.0 Nord conversion on Weber 40鈥檚 and love it. However the cab stinks of fuel after driving ....
I'd be concentrating on fixing the fuel smell in this race car. If you have a leak, your car will potentially become a fire ball on the side of the track.

Webers should not make any more fuel smell than ITBs.

Pete
 

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A few of us have used motorcycle carburetors (which are individual to each cylinder) with a lot of success. Those can be cheaper than the fuel-injected alternative. I think Toyota 4AGE's also came with ITBs from the factory that you may be able to retrofit.
Weber side droughts are individual to each cylinder too ... so can't see the advantage here, as good as motorcycle carbs are.

Pete
 

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I spent around 2k on converting to EFI.
Emerald ECU. 拢700
Air temp, throttle pot, water temp, crank sensor. 拢75
Fuel swirl pot and high pressure pump plus new feed line and return regulator. 拢125
Wasted spark coil pack. 拢30
eBay throttle bodies 拢350
Injectors. 拢80
Trigger wheel 拢12 plus machining 拢 30
Wire and relays
I also added a zetronix O2 sensor and digital display, the ability to datalog by rpm was very helpful in getting a base map sorted.
Trigger wheel.com and emerald have most of what you need, eBay the rest

Webber's don't make more power how can they? Big mistake is to over size the throttle bodies which looses torque remember 45 Webber's probably have 36 Venturi so a 40 throttle body has more open area, yet everyone goes for 45 TB this slows the air velocity reducing cylinder fill at the bottom of the piston stroke
I got 48 ITB, and so much torque low down any granny can go shopping. even with the racing clutch.
 

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Weber side droughts are individual to each cylinder too ... so can't see the advantage here, as good as motorcycle carbs are.
I'm not super familiar with Webers, but I thought each couple shared a bowl and some of the fuel circuit? Could be wrong...
 

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Gotcha. I'm famiar, via this board, with using motorcycle throttle bodies for aftermarket EFI conversions, had not heard of people actually running motorcycle carbs on auto engines. Cool.
 

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1985 Spider (SSM AutoX)
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Gotcha. I'm famiar, via this board, with using motorcycle throttle bodies for aftermarket EFI conversions, had not heard of people actually running motorcycle carbs on auto engines. Cool.
It's fairly popular with EU/UK folks for Ford (Escort) applications and Lotus 7 kit cars (DanST engineering makes manifolds and conversion kits.) VW folks in the USA use big YZF-R1 CV carbs in caddies and rabbits, and Japan peeps go wild with Keihin FCRs in N1 AE86s.

EDIT: I ran YZF R1 Mikuni CV carbs for several years with great success, road and track. Swapped early last year to Keihin FCR 39s on a new custom manifold built on the stock Bosch manifold baseplate, again great success. @MarklotS had Keihin CVK40 carbs off of a ZZR1200 on his Nord before starting his K20 swap project.
 

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Weber side droughts are individual to each cylinder too ... so can't see the advantage here, as good as motorcycle carbs are.
Webers share a bowl but have separate floats so... You're right. There isn't that much difference save for different throttle valve shapes and a more modern design. CV carbs should have an advantage in metering under load, and a select few bike carbs are flat slides which is an (arguably) better throttle valve design.
 

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I'm not super familiar with Webers, but I thought each couple shared a bowl and some of the fuel circuit? Could be wrong...
They share a fuel bowl, that is all. Effectively 4 carb's on our 105 series Alfas.

Funny thing about motorcycle carbs I've played with, and that was only on my Suzukis, was they are a modern version of the old and wonderful SU carb
Pete
 

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Discussion Starter · #34 ·
Realistically what is realistically achievable power output for a TS Nord with EFI and throttle bodies,? Bearing in mind Alfaholics promise more than 220bhp for in excess of 拢30k spend.

Thanks to your advice it looks like I can get near this for around 拢5k. Can anyone recommend someone with experience to optimise the gas flow of the TS head. Looks terrifying after reading Jim Kartalamakis鈥檚 book!
 

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Bearing in mind Alfaholics promise more than 220bhp for in excess of 拢30k spend.
I'll be the first to comment since I am the one lunatic idiot with bike carbs in his cut up Spider (I clearly don't care about my reputation.)

I know that's what Alfaholics says, and I love their stuff (got many AH bits in my spider), but 220 bhp sounds... 'bit optimistic. I've been watching the dyno charts published in the forums for a while, and I think realistic Nord limits with mid-high compression and headwork are right at the 190-200 crank. I don't see why a well built TS head Nord with EFI, mild to high comp, and a competent tune wouldn't get in that range with much, much less than $30k GBP spent.

With modern headwork you might not even need the TS head to get there, and I am not sure how much it would help (if at all.)
 

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@PocketAce is the 220hp AH promise for their 2.3 litre version? As then it would make sense.

BTW Msiert is who everybody should follow on this site. He made a great and powerful road engine for his black Spider, with ITBs. See: Msiert's Black Spider Project
Pete
 

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Xenios
May I drive your Giulia if that was yours in the video? I have a 1700 67 Alfa Spider and a SPICA 1969 Spider.
The SPICA is not as much fun. I was able to monitor my engine exhaust burn with a Zeitronix. It is something I can do.
Not mine, someone shared it on a 105 Facebook group a couple of weeks ago.
I own a 1969 1750GTV with 2.0 spica.

Sent from my M2011K2G using Tapatalk
 
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