My Strombergs needed a rebuild,
but instead I wanted to upgrade to SU’s. To save money I bought these from a Jag-Lover Classified:
Joe Curto rebuilt the carbs while I cleaned the rest. I nickel plated the linkage with DIY instructions from the “Instructables” web site.
Assembled and then tuned using Ray Livingston instructions and a Unisync…
It starts quickly, idles smoothly (600 rpm), and pulls smoothly. Fresh SU’s are better than old Strombergs.
Thanks to Ray, Joe, & Jag-Lovers
Verry nice, and I see you have the vastly superior 3.8 manifolds too 
Cheers,
LLynn
Cooler looking, for sure!
Jerry
Nice!
Just curious what was the math on buying a ready to go set versus buy a project set of carbs + cost of a Joe rebuild?
Philip, The full conversion kits are now 5 grand! I spent $1400 for the old parts and shipping. $850 for Joe Curto & shipping. $400 in new parts including the triangular air box that is not in the kits. I was lucky to find the old parts.
Is the 3.8 manifold and linkage a direct bolt-on to a 4.2 or do you have to do any mods ?
Guess I still need to drive or go for a ride in a SU car. I have driven a Weber 4.2 but was not sufficiently impressed with that particular one over my Strombergs to motivate me more to make a switch. My Strombergs do start quickly, idle smooth and pull smoothly especially now that I have adjustable needles and was able to lean out the mixture some from what the original “fixed” needles were doing.
David
68 E-type FHC
David,
“Jaguar E-Type Collector’s Guide” gives road test results from the day:
S1 4.2 OTS 0-60 3.07 axle 7.4 secs - SUs
S2 4.2 OTS 0-60 3.54 axle 7.2 secs - North American specification, presumably Strombergs; European specification (SUs) with 3.07 axle: 7.2 secs
0.2 second drop to 60? No reason to do it. Certainly very close to the same, different drivers?
Very cool looking SUs? Some will spring for it!
Jerry
Morning David,
As one who has changed to SU’s from dual ZS’s I agree completely with Jerry. I really like the ‘cool’ factor with the SU’s but aside from that it’s just that much more hassle to tune and maintain, which isn’t really that bad but…
Cheers,
LLynn
Take out the second set of throttle plates and their shaft and fit adjustable jets and the difference probably shrinks.
Three SU’s do look a bit cooler than two Strombergs; but do they look $5,000 cooler?
A different test result – all from one magazine (R&T)
('64) S1 3.8 FHC 3.31 axle 0-60 7.4 secs
('69) S2 4.2 FHC 3.54 axle 0-60 8.0 secs
So, half a second slower, with a 3.54 axle. In my experience my 3.8 has a lot more snap than any 4.2 I have driven (fun!) but not much measured difference in acceleration.
Jerry
in the 70’s I installed SU’s, headers and glass pack mufflers on my 69 ots. car was wickedly faster. even the mechanic said “wow”.
David, The mods to fit the 3.8 manifolds to the 4.2 were all plumbing. It needed 2 freeze plugs in coolant ports that the 3.8 does not use, And 4 custom coolant hoses that I cut from longer hoses with the right bends from Autozone. I added a vent hose attachment to a cover plate near the thermostat for the small hose that runs to my S2 radiator.
My parts came with the throttle linkage from the firewall including the bracket and bushing near the wiper motor. It bolted up and adjusted with no mods. I just used the long choke cable & tucked the short one out of sight.
So nothing expensive or permanent.
I told myself, I was doing this for drivability & the car is much more drivable. BUT if I had well tuned Strombergs with adjustable needles, then I would have saved my money.
& one more plumbing mod. My car had long pipe under the manifold ( heater return to the water pump.) Mine has a T that Cound have plugged, but I replaced it with a straight pipe.
