I've read diagnostic questions of other members in refrence to tuning a 292, and found that we share simliar problems, my 292 is running , Idles fine while cool, but backfires when warm or under a load in high gear(load meaning ...hill's,etc), some of the things I've done to try and correct this problem ,replace the distributor(with rebuilt) rebuild the carb (twice, just to be sure) and I'm in the process of making adjustments to the , points, adding new spark plugs and wires double and triple checking timing. And just to be sure, begging for help with firing order, timing marks, plugs to use, wires to use, gap settings for plugs and points, and any other usefull information I can gather from the "Y - block Gods" here at FTE, thanks all in advance, .....58tow

 

Sounds like it may be that you're spark advance isn't quite right. Here's a link to a short primer that might give you some ideas:
http://m571.com/yblock/advance.htm

This is a page about tuning the distributor:
http://m571.com/yblock/distributortuning.htm

And I guess I should add the link tohis home page too:
http://m571.com/yblock/index.htm

 

Welcome to FTE! Plug gap .035, point gap .014 - .016, timing 8-10 degrees, plugs Autolite 46, firing order 15486372, front passender cylinder #1, front driver side cylinder #5.
Things to thing about: Crossfiring between plug wires, hookup of distrbutor to proper vacuum fitting on carb, worn timing chain/gear, shift of timing mark on damper due to rubber deterioration, vacuum leak, valve lash adjustment. Maybe one of the guys will get it more narrowed down for you.
Mike

 

did you check your valve ajustment ?