Webers on a Healey 100

[Guido36]

I have acquired a pair of Italian made Weber 48 DCOEs on custom fabricated manifolds which were installed on a BN1 race car with a stock type (non 100S) head and plan on using these on a 100 with a DWR head. Has anyone else used side draft Webers on a 100 4 cyl engine? Any advice on setup and jetting would be much appreciated….

 

[Randy Forbes]

Jetting/tuning is very much an individual engine thing (while it's at least a place to start from) I doubt you'll run into too many seemingly identical engines running the same jets.

Forty-eights (48mm) are pretty big carbs, and unless you're planning to run WOT ALL THE TIME, you may consider fitting them with the smallest chokes you can find (there's a formula for choosing these based on cylinder volume; if you can get the Weber Carburatori Assistenza Technica, # 95-0000-54, it will greatly assist you, and it is printed in English ).

I have a trio of the 45s on my 180.0 cubic inch engine (+.030" = 30 ci/cyl) and because the car is primarily street driven, I chose one siz smaller chokes than commonly used on racing engines, to maintain a higher velocity through the bores, otherwise, low speed throttle response is the pits.

These have been on my car since 1985, and once the jetting was figured out, only "adjusted" when I moved from Louisiana to Ohio, then once again when moving to Florida (trick is to get them right, then LEAVE THEM ALONE).

 

[Guido36]

Thanks for your insightful reply Randy - certainly food for thought. 48 DCOEs are very similar to 45s except for the early ones which have straight bodies rather than the stepped bodies of the later 48s and all 45s. I currently run four early 48s on my Ford 289 HiPo powered BN1 nasty boy. I run 38 mm venturi on these. I am thinking of modifying a stock 100 to fast road race specs. On V8s Webers like plenty of lobe separation - I run a solid lifter cam with 114 degrees of separation and no more than 3-4 psi fuel pressure. Alfa Romeo ran 45s on the 1600 GTA (97.5 ci) so I am not overly concerned about the bore size and with variable venturi they can easily be sleeved down to as small as 32 mm.

 

[Randy Forbes]

Ah, well then, I'm preaching to the choir! Carry on

However, if you want to practically forget about jetting altogether, you might consider the next step (and selling those original 48s would offset the cost substantially); Borla 8-stack I recently fitted to (427 FE) Superformance Cobra. Holley TerminatorX handles management for fuel & ignition.

 

[twas_brillig]

Lord! My eyes hurt just looking at the photos! My head hurts considering the complexity!! And my heart warms as it is admiring the work that has gone into setting these up.
On a different note, I've apparently got a masochistic streak as I've been trying to convert a 1972 BMW 2002 to EFI, using gutted Weber DCOEs as throttle bodies. I surely didn't understand what all was required, as we've spent a couple of years trying to get modern high pressure port injectors to work in a throttle body application (we'd welded injector bosses underneath the Webers to produce a throttle body system - which won't work with the injector combination we were using). Now trying to obtain affordable aluminum welding to add injector bosses to the underside of a manifold to produce a standard modern system and so we can retain the DCOEs as throttle bodies, and have an engine compartment that looks like a period correct hot-rodded 2002. However, it also looks like the ECU system I have may not be suitable for what will be an Individual Throttle Body system. Sigh!!

 

[Guido36]

DCOE type throttle bodies have been around for some time….

BMW M10 - Heritage ITB Kit

BMW Individual Throttle Body (ITB) kit for fuel injecting your BMW M10 4 cylinder from Jenvey Dynamics includes a pair of TDP45 Heritage throttle bodies,a Jenvey Dynamics EFI inlet manifold and 40mm long airhorns. Jenvey throttle bodies and all Jenvey throttle body accessories are engineered to...

store.jenvey.co.uk

 

[Guido36]

Funnily enough, I was negotiating to acquire TWM who were the originators of the Borla induction range, in 2006/7 but market conditions were not favourable and Alex Borla already held a 30% stake in the company.

I wanted Webers on my nasty boy to give it a ‘what if DMH had built a V8 Healey’ vibe - something that has been hypothesized over the years and may have been a consideration were it not for Austin/BMC control. Carroll Shelby, having been a works driver for DMH is said to have favoured the Healey with a Chevy V8 but resistance at both Austin who did not want a third party V8 rival to the Healey and Chevrolet who ddid not want a rival to the Corvette nixed that idea, so Shelby went to the Hurlock family at AC and to Ford and the rest - as they say - is history. I also specifically wanted to run side draft carbs so as not to have to cut a hole in the hood. Borla does offer throttle bodies with a Weber style 48 IDA body which look close to actual Webers.

Weber IDA Replacements for Volkswagen Type 1 and Type 4

Weber Style Throttle bodies for Volkswagen Type 1 and Type 4

www.borlainduction.com

The cost of using Weberalike throttle bodies is about double the cost of Weber carburetors - Inglese - under Comp Cams ownership - used to private label TWM throttle bodies which they would market as complete systems with third party intake manifolds, and their subsidiary F.A.S.T. providing the ECUs and associated electronics.