Is it ok to put 91Y tyres on my vrs hatch rather than the 93W that were originally on it

W rated tyres are for 168mph. Y rated are for 186. 91 is 615kg and 93 is 650kg.

It's an upgrade - I think you'll be alright.

I was thinking of going from 93w to 91y speed rating increased but weight decreased but by only 35kg per corner but going by the weight of the car I was thinking it should be OK or am I missing something

Apologies - I was reading the W to Y and had it in my head that it was an upgrade on both counts.

I'm not sure what the GVW/MAM is for a Mk1, but for a Mk3 it's just over 1900kg. With 91 tyres all round you'll be about half a ton off that. Even if you were to be transporting lead, I think something else would break before you got a tonne of weight in the boot. You'll be fine.

I was thinking the same

I mean put it this way - most newer Octavias can do about 600kg or so. Even if you managed to put more than that, the boot would collapse at about 750kg. Add the vehicle weight to this and you're still several chunkies short of the weight limit for the tyres.

I think kerb weight for a Mk1 is about 1350/1400kg. We're talking about a tonne of extra weight before you begin to run into issues - that's five 130kg chunkies, a full tank, a dog and about 200kg worth of luggage.

Lol

yeah- I was worrying about carrying 210kg of slabs the other week until I read up on this. But the car felt slow and low - even if I had 600kg as acceptable payload, I wouldn't have considered more than 200kg, speed bumps would be painful. My Mk1 is old and sometimes feels like it

Generally speaking (trench blocks come to mind), you'll bust the suspension or structure (boot/cabin floor) before having any issues with tyres. it's actually quite difficult to go over the max load for a passenger car, unless you are transporting lead or bags of cement.

The extra weight is definitely noticeable, no matter the car. I notice the difference with just a full tank of fuel. That's not to mention if I put a suitcase or two in the boot, the front of the car becomes a monster truck. Stiffer springs are definitely needed.