What is the proper mounting angle of the engine and transmission. In photos it looks like from 3-6 degrees. Anyone know what the factory mounting angle is?

 

The angle doesn't really matter, but the crankshaft centreline does need to be parallel to the pinion centreline in your differential. Then the angles in the U joints in the driveshaft are the same at both ends and you won't have vibration in the driveline. They don't need to be on the same plane, but they do need to be parallel.

As you have a custom car, you'll have to match whatever your rear axle is. 3° is a typical angle from the factory.

Spicer has some good guides for driveline layout, this one will tell you all you need to know: https://media.spicerparts.com/cfs/fi...store=original

 

I've got some clearance issues with my current air cleaner intake and I want to use the shorter version. The air cleaner is protruding through the hood right where the hood hinge is located (red line in photo), it needs to be a couple of inches lower at the top. There will be some of the air cleaner protruding no matter what, I have to keep it clear of the hinge.
The photos I've seen of the shorter version shows it has the same bolt pattern as mine. Do these two carburetor air cleaner intakes have the same carburetor spacing?


This is my current setup.

 

The one you have used has a round upper opening and is the same as the S Type. The second version you call the shorter version has an oval opening at the top and was used on the Mk2. Both engines used the same carburettor set up as in twin SUs so there should be no difference in how both mount to the carburettor's.

 

If you need to custom manufacture an air intake to replace that cast piece, keep in mind that your minimum distance of a flat piece to the carb face is diameter of the diameter of the carb bore /6.

An example: To keep the math easy, if the carb bores are 2", then you could bring a flat piece of metal as close as 2"/6 = 0.333" without restricting air flow. This is commonly used as a way of making air do a restriction-free 90 degree turn.

 

I currently have phenolic spacers on the carbs. Are these spacers necessary?

 

For a one off special period car, I would consider a simple air filter that will help with low end torque.
https://mossmotors.com/37-0875-foam-round-air-filter-1-3-4-su

If you want you can fit a stubby Velocity Stack
to improve flow. inside the filter 1-3/4" SUs, 1-1/8" length

https://mossmotors.com/37-1584-cp-su-velocity-stacks

Rgds
David

 

Yes for 2 reasons. They are a heat insulator, and they provide clearance to allow the throttles to open fully. On most Jaguars, if the spacers are omitted the carb throttle levers will hit the manifold.

 

Pancake airfilters are nothing but stone catchers including the oiled variety. Use the OE casing with Mann (Mann + Hummel) elements. ~ the best!!. If I was talking hydraulics & fluids I would say Donaldson. I'm a Tribologist with a Supermajor oilco. We've tested them all. There is some real rubbish out there. I heaped teaspoon of dirt/silica dust will ruin an engine.

 

A bulge on the side of the car to accommodate the standard air box could look good. Or even a hole that shows off the polished aluminium to the world.

 

I would think that if it's only minor surface rust, and you have lubricated the bores, that a few cycles of hand-cranking, then some rotations on the starter motor would be a good strategy

 

Cummins made a film all the way back in the 1950's called "The Hourglass". It is as valid today as it was all those years back with those old vehicles. Only difference is that today some filters have improved.

 

Is 165-170 degrees F the proper operating temperature for a 3.4?

 

I have a custom drive shaft with a Jaguar flange mount bolted to a Spicer flange u-joint yoke. The drive shaft shop said a grade 8 bolt with a shoulder the length of the 2 flanges thickness would be ok. I assume Jaguar had special flange/shoulder bolts. Is it necessary to use a special bolt or will grade 8 be sufficient?

The car is ready for some test runs, I hope to drive it a little this weekend.

 

Jaguar used ordinary bolts. Grade 8 is more than sufficient.

 

My 3.4 runs at 45 to 55 C all day long which is around 115 to 131 F. If it creeps up over 70 C 158F then I start to worry and this only happens on a hot day when I am stuck in traffic.
I am based in the UK and the reading taken from my temp gauge which might be reading low as I have never checked it with any other device. Engine is fully rebuilt, cleaned, serviced and has a new radiator. I do not run an auxiliary electric fan just the standard fan on the front pully.

 

Are you sure the gauge is reading correctly? Assuming you have a good thermostat, it should come up to that temperature (74°C), as it's the thermostat's job to maintain a minimum engine temperature.

You do want it to run hotter than 50, the reason is to boil off the moisture that is a byproduct of combustion. I'm sure Glyn can clarify, but usually minimum oil temperature is around 75-85.°

 

much to my surprise, i've found that there are a number of temp sensors that will fit in a mk2 thermostat housing. and it wouldn't surprise me if there were a number of slightly different housings used over the years too. the sad part is that they all look pretty much alike. i now own four of them! few will fit and many don't register the correct temp on the gauge.

it appears that some have more threads on them than others, making those that do bottom out too soon and consequently making a water tight seal impossible. all have a plastic like ring just above the securing hex nut but in varying colors. sometimes the nut is not the same size, i've had whitworth sized heads and metric too. they do not all register the same resistance and therefore the same temp readings on a gauge either. in addition, the gauges themselves register in centigrade or in Fahrenheit, nothing wrong with that, but may be the root cause of the varying resistance they register while sensing the same temperature.

mine, clearly aged, on a freshly rebuilt engine (don't know if they swapped it for a different one that WAS on the engine when they received it) registered 20C too much, only one of the new ones registered a temp that matched that from my laser temp reading gun. and all the new ones had too many threads and there were at least two different colored rings and only one was advertised as fitting the MK2, and it had so many threads on it that i couldn't even mount it to test its accuracy.

the one i'm now running reads about 85C on a 20C day. i plan on removing my thermostat to check its opening temp value and have yet to double check the sensor's accuracy with my laser gun, but will as i'm satisfied for the time being to have it read something south of 110C!

it's a jungle out there...

 

That is correct JB

 

I tuned to the SU HD6 carburetors according to the manual and set the timing also, and the engine is idling smoothly. I drove it a little today and it runs smooth then a little ruff, and sometimes under acceleration I get random small cough/backfire on exhaust or intake.
The distributor, plugs and wires are all new.