405 wheels touching arches

[Atlaskrukvaxt 5]

Hi! I recently bought some 7x16 et15 aez alloy wheels as seen in this thread. 

I don't mind the wheels scraping the hull at full turn but the issue is when I drive over speed bumps at anything besides crawling or if the drop is "too high" at the end of the bump I get scraping in the right (passenger) side wheel arch regardless of how careful I am. If I have one or more passengers or a boot full of stuff both sides scrape even when going carefully, and I mean crawling, over the speed bumps.

 

I believe it's quite a common issue on 405s that the rear suspension becomes softer as they age and rust. It happened on the SRI that my dad owned previously too before he changed to a 1.9TD estate. So I'm thinking of putting either a new jumper/berlingo rear axle or just replacing the torsion bars to something stiffer (since I have ABS and disks all around, which is a bit uncommon on the vans I think) to prevent the wheels from scraping just because I'm going over a speed bump at 11 kph rather than at 10kph.

 

However, I'd like to know if this is enough to mitigate the problem or will I have the same problem because the wheels are ET15 and not ET 20 as I believe are suggested for mi16s?
Would the chassi suffer due to the stiffer torsion bars?
What kind of torsion bars would be enough for general road application? (I saw the article by welshpug where he put the rear axle from a berlingo 600kg i believe but I think they might be a bit overkill. Please inform me)

 

Thank you for reading. 

[welshpug 1,666]

6" 405 wheels are et 28 or 19, so your 7" wheel at et16 would be much closer to the arch, 15mm or so to the lower offset version.

 

your tyres are also bigger than oem by 35mm diameter,b205 45 16 would be closest to the original 195 55 15, that will fix the problem.

 

old springs are not the problem, yoi could remove the spring totally and the tyre would still not rub if it was the correct size and correct wheel offset

Edited July 6, 2020 by welshpug

[Atlaskrukvaxt 5]

Thank you Welsh, I guess I'll have to suffer in silence for the rest of the summer and go with the lower profile tyres after.

It's a shame cause I've had good use of the higher ride height while driving along some of the more questionable back roads of my town.

 

On the SRI that we had the wheels scraped with the 195/55/15 too if you had 2 people sitting in the back.

I remember quite clearly driving with some of my cousins (who are admittedly a bit on the larger side sizewise) on previously mentioned back roads and having almost no clearance in the wheel arches. Vegetation brushing the floor pan on dirt roads and the distinct sound of arch scrape when driving over dried up puddles is etched in to my memory.

 

That car was almost leaning backwards though.

 

Thank you again.