I played around with my adjustments today, now that I know (3 years later! ) how to properly adjust the throttle arms with the turnbuckle.
So I went back to square one, as the Jaguar Manual says, and made sure the throttle plates were at .002" clearance, the throttle stops were set, and the intermediate linkage bellcrank was on it’s closed stop. I then adjusted the throttle rods on so they fit perfectly, with bellcranks still sitting on stops.
Idled great, but I got a terrible pause on slight acceleration when cold, and a subtle pause on slight acceleration when warm.
The problem is, and I don’t know if this is normal or not, there is a tiny bit of slop with the intermediate linkage. That rod that connects top to bottom is where the slop is. So as the throttle pedestal starts turning and pushes the throttle rods, it takes about 1-2mm movement to open the actual throttle bodies, and you get that ‘pause’ . TPS is going up in voltage so ECU is providing more fuel, but throttles are still closed.
So my solution was: I gently turn each throttle rod by hand to take up the slop until there was resistance. I double checked with the 0.002" feeler gauge on the throttle plate stop screws (Not throttle plates) to make sure there wasn’t a gap, that I didn’t turn too far (it’s easy to do). Also, it’s important to do it on a hot engine. The throttle rods expand! I at first did this cold, and then by the time the engine warmed up, the rods were pushing a bit too much, I had gaps at throttle plate stop screws. Was wondering why idle went up.
I still get a great idle, and now no pause when giving a slight acceleration. There is a wee tiny bit when engine is totally cold, due to the throttle rods contracting. But it’s subtle, and goes away by 160F.
Only isssue, the intermediate bellcranks are no longer on their stops, they have a 1-2mm gap. The throttle stops provide the stop all by themselves. I don’t understand what the bellcrank stops are for?
On a side note, my idle has improved! When checking my throttle plates, sure enough, they were both sitting a micron too low. The 0.002" feeler slid a bit free on top, but wouldn’t budge on bottom. I loosened both screws and adjusted, and now it’s 0.002" top/bottom. The throttle plate is perfectly centered. Don’t know why, but this seems to definitely help smooth out the idle. Air flow pattern?