TR2/3/3A '59 TR3A Rebuild, Canada

Have finally finished rebuild on 1959 TR3A. Car (ex-California) came with SU's that had capstat jets and TR4A carb linkage. I have just installed new SU HS6's. Car will only run with choke on, runs rough and backfires through carbs and exhaust. Running Flamethrower Electronic distributor (cap a bit sloppy, came that way) and Intermotor Sports Coil; Champion plug gap 0.035" wouldn't run with NGK; static timing set as per manual; tested resistance of plug leads OK; rotor seems OK; Exhaust/inlet manifold torqued to ~26lb/ft; valve gap set as per manual; compression 175psi 1, 2, 4, #3 was 165psi; running 91 octane fuel; new fuel filter; Started with jet set 12 flats down, cannot get car to idle without choke full on which of course prevents carb set-up. I tried 18 then 24 flats down to maybe allow to close choke, backfire worsened each time. Any suggestions would be appreciated. David

Check for vacuum leaks where the manifold meets the head. There are two pins that are supposed to locate the manifold; but its easy to get it on top of one or both pins. The top looks fine, it's the bottom edge that leaks (where it's hard to see).

I'd also hook up a timing light and see if the spark is doing anything funky. I'm not a fan of Pertronix electronics.

Hi Randall, I've read a lot of your posts, thank you for your contribution to the TR questions. I will check for leaks again. Ironically, prior to the rebuild the Pertronix worked great. I agree about the manifold leak, in that I believe I had that due to the confusion I experienced when torquing the manifolds, in that the shop manual gives two different torque values for inlet and exhaust yet they share bolts/nuts. Any particular exhaust/inlet manifold gasket material/treatment you recommend? David

That's odd; mine just says "manifold bolts", 22-24 ftlb. (Although I did just spot a misprint in the service note; I'll try to remember to fix that when I get home.)
https://drive.google.com/open?id=0B2H2NJt34OffYWZiN2VlZGMtNTkxMi00NGUzLWE4NzMtMGRkODRkYzU3MDU1

Could you be looking at "Inlet to Exhaust manifold" ? Those are the two smaller bolts that connect the two manifolds directly to each other (which I don't even install).

I install those gaskets dry; they shouldn't need any goop to seal.

The only "trick" is to be sure the surfaces are flat; several times I've found the head surface is "pulled" around one or more studs. Take the studs out (and the pins if you can get them out), then rub a flat machinists file over the surface with light finger pressure. It will pick up any high spots, which you can continue to work down until it starts to polish the entire area. Not likely you'll find a low spot, but that will show it if there is one.

Spin the nuts down the studs to make sure the threads aren't distorted. Manifold studs aren't so critical, but if one is distorted it's probably best to replace it rather than trying to chase the threads. New lockwashers, every time; and check the nuts for tightness after the first heat cycle and again after a few hundred miles.

I also use heavy flat washers (aka "setup" washers) on the two outermost studs (the ones that don't have a bridge piece).