88.5mm stroke is excessive to say the least for the a series short block height.. Unless you can increase the block height with carefully welded deck plate, sleeves and longer lightweight pushrods.

Some of the best race engines have 86 - 90mm strokes but have the right block height for longer rods to help with RS ratios.

I dont think 85-/+0.5mm is excessive though with the 133/134mm rods.
By using motorbike rods with 35-40mm journals inbuilt threads (some are titanium) and available in 133-134mm (have to research this yourself as rod dimensions of stock bikes is not easily found.) you will be able to get this slight increase in stroke and not have to overbore beyond 77 -/+0.5mm.
The midrange should be better than the 82mm stroke and longevity can be increased as can heat transfer between piston bores. If something goes wrong you can safely re-sleeve to remain within the 1.6 class limit.

In offroad racing circles where torque is favoured over hp the suzuki 1.6 with 1.533 RS ratio does wonders with durability once the rods and rod bolts are replaced with quality items and well balanced.