Torque converter change needed?

Hi guys, first post from Australia.

Going to be installing a 350 sbc or maybe an Aussie Holden 308 motor to a 77 series 2 xj6. I have the new bellhousing to fit tne new motor, but was wondering if my camshaft rpm range is a little higher tnan the jag motor, will I have to change to a higher stall? Say 2500?
Thanks for any advice, and if I do need a bigger converter, where do I get one? I’ve heard just modifying the stock one is not the best?
Thank you

Not really enough info to say.
What cam specs?
What gear and tire size?
I’m assuming jag/gm th400??
What kind of driving do you do with it?

Hi Jay, sbc with 280H comp cam 230/230@ 50
Stock 3.31 ? Gears with the M12 Borg Warner trans.
Just a nice warmed up street cruiser.

What’s the torque range of the engine you are going to use? The 4.2 peaks around 2,800-3,100 from memory but I am sure someone will confirm the correct figures.

that’s a fairly choppy cam. it’ll come alive around 3000rpm.
i think comp recommends 2500 stall.
i’d say that’s at a minimum. you will want a 2500-3000 converter, at least 3.73 gears, and 9.5 compression
3.31 is not far off.
if it were my car i’d go 3200 stall.
i have a slightly smaller cam in my '71 xj6 with an LS1/4l60e 3:54 rear and i went with a 3500 stall with a big trans cooler.
works fine for a daily. when i floor the loud pedal the converter flashed to about 3000-3200 and wants to break the tires loose. it’s a fun daily sleeper.
the best thing ot do may be calling a local trans/converter builder and tell the the car specs, weight, gearing, cam. driving style/intention, etc and have them build a converter tailored for you and your car, instead of off the shelf.
Hughes converters here in the states does that. shipping may be $$$ to you

got any pics of the car?

Use rthe converter from the donor cr…