[sunikkat]

Originally Posted by X0mbIE

95k total for both front and rear dampers ?

Yes, thats right - 95k overall. Front dampers are more expensive than rear.

[amitmanjul]

Hi, I could write a few chapters on this issue, detailing my costly mistakes & what I finally consider as the best compromise.

I drive a 2018 model 1.8 TSI. Immediately out of the showroom, I changed the tyres to Michelin 3ST in OEM size. However, I was still not comfortable with all the wallowing & upgrades the struts to Bilstein B6 in 2019. It immediately improved the handling but the stiffer monotube struts ended up raising the ride height substantially, by about an inch.

The large empty wheel wells looked rather ungainly & I initially experimented with Eibach springs which improved the stance & cornering was a dream but I was scraping even the low humps and the ride became too stiff.

Back to the OEMs, before another experiment with Cobras springs with 1” aluminium spacers. The spacers took care of the height but the ride was just not comfortable enough on the potholed Bangalore roads - so back to OEM springs once again.

I then tuned my car, gave it a MST cold air intake & a DO88 intercooler. However, the OEM spec tyres screeched their lives out, unable to manage the 230 bhp & 350 NM of torque (measured at the wheels).

To provide more grip, I upgraded to 17“ alloys & shod them with 225 45 R17 Michelin PS4 tyres - and this combo is the best that I have experienced.

So Bilstein B6, OEM springs & upgraded tyres/alloys get my vote!!!

But their is a sting in this tale - I also have OEM Euro spec springs & bushes for Octavia lying with me…..let’s see when I get the itch to try them as well!!

[X0mbIE]

Originally Posted by amitmanjul

So Bilstein B6, OEM springs & upgraded tyres/alloys get my vote!!!

Really appreciate sharing the whole experience. Thanks. So with your best set you were still not able to get around the 1 inch increase in ride height ?

[itwasntme]

Originally Posted by amitmanjul

However, the OEM spec tyres screeched their lives out, unable to manage the 230 bhp & 350 NM of torque (measured at the wheels).

How's the DQ200 faring?

[amitmanjul]

Originally Posted by itwasntme

How's the DQ200 faring?

Touchwood, no issues at all, Anyways, my car is 2018 model which has the Gen 2 of DQ200 (this got flashed when the car was being tuned). 2018 onwards not much complaint on the gearboxes

[amitmanjul]

Originally Posted by X0mbIE

Really appreciate sharing the whole experience. Thanks. So with your best set you were still not able to get around the 1 inch increase in ride height ?

Ultimately I made peace with that 1 inch gap The workarounds through eibachs/Cobras were too harsh for potholed city driving. Possibly because I was on the already stiff monotube Blestein B6s.

I still thank that with the softer OEM struts, the cobras with spacers should work out just fine.

[evil_grin]

Originally Posted by amitmanjul

So Bilstein B6, OEM springs & upgraded tyres/alloys get my vote!!!

But their is a sting in this tale - I also have OEM Euro spec springs & bushes for Octavia lying with me…..let’s see when I get the itch to try them as well!!

Thanks! Your detailed experience is extremely valuable.

I went on a long drive, some of it over bad roads. I appreciated the soft suspension more than I disliked the wallow at lower speeds when unloaded. It's important to keep it comfortable.

So here's what I've decided. Wait for the the stock dampers to wear out. Then replace with RS 245 dampers, if available, else Bilstein B6. It that solves it, great. Otherwise, change the springs to RS 245 as well.

I expect the stock dampers to wear out after around 80k km, which is around 35k km and a little over 2 years away.

[amitmanjul]

Originally Posted by evil_grin

So here's what I've decided. Wait for the the stock dampers to wear out. Then replace with RS 245 dampers, if available, else Bilstein B6. It that solves it, great. Otherwise, change the springs to RS 245 as well.

I expect the stock dampers to wear out after around 80k km, which is around 35k km and a little over 2 years away.

I think you are on the right track.While it is exciting to throw the car fast around corners with a firm suspension setting- but 90% of the time it is either highway cruises or city rides where comfort is important as well.

Bilsteins or stock VRS struts should do the trick. You will of course research on matching spring & strut ratings - you have 2 years to do that

[evil_grin]

An interesting development.

I always keep my cars pressure at 29 psi. That gave the best balance of ride quality and pick up. At least on my Honda City.

I continued the same with the Octavia. Had briefly tried higher pressures. Even 30 felt too harsh with the rubbish stock Goodyear Eagle NCT tyres. So went back to 29.

I continued with 29 even when I upsized the tyres to Michelin P4 ST 205/60/R16.
Then when I got a sidewall cut and a sidewall bubble on the nasty potholes on the Nagpur Hyderabad highway, I let the tyre shop (Ashoka wheels, fantastic shop btw) inflate it till the recommended 33 psi after replacing the tyres, thinking maybe this will reduce the chances of sidewall damage again.

Ever since then, the wavy motion has reduced and the steering has better feel and feedback. There hasn't been any deterioration in ride quality. A lovely unexpected outcome.

Does that rule out suspension upgrades? Nope. They are the most underrated upgrades.
It just makes the car more fun to drive until the time to upgrade the suspension comes.

[Poitive]

Originally Posted by evil_grin

An interesting development.

I always keep my cars pressure at 29 psi. That gave the best balance of ride quality and pick up. At least on my Honda City.
...

Mate, please reconsider not sticking to manufacturer recommendations. In general, better to stick to those and adjust a tiny bit as per load on the vehicle and personal preference. Overinflation is more acceptable than underinflation (10% over is usually considered okay, and some say even 15% or more; not so for underinflation).

Underinflation in particular can be dicey; especially in more extreme use (planned or finding one's self in a near accident situation) :

• It heats the tyres, increasing chances of a blast. Especially on long highway drives.
• Heat also makes the compound softer than ideal. Typically it would result in more grip and tyre wear; however this might not be consistent. Not sure, but I suspect after a point, it will reduce grip, and possibly in a sudden manner.
• It would also make the car a tad more prone to punctures.
• The sideways are more prone to damage, as you too experienced.
• With lesser pressure the sidewalls flex more.
  • Hard cornering can be dangerous, as if the flex is excessive, the composure of the car can be lost (and possibly quite suddenly), and it can result in a cut of the sidewall. This would typically only be in more extreme situations; say while avoiding an accident.
  • More flex of the sidewall will also wear it out faster, further increased by higher temperatures.
  • More flex also means more side-to-side movement.
  • Generally, the car will be a bit less predictable in hard driving conditions.
• There would be tiny delay in the response to steering inputs, as a softer tyre setting (ie lower pressure/sidewall with more flex, in this case), would partially absorb the change in direction input, and then react. The car will feel slower to react to someone sensitive to it.
• Since an underinflated tyre is in a sense like softening the suspension to an extent, the feedback of the road will also be lesser - felt both on the steering and also the ride quality (can be seen as an improvement in ride quality)

Overinflation would give the feel of a lighter car, and in most situations be faster, due to lower rolling resistance, but would the contact patch, would also tend to skid more easily (or trigger car electronics accordingly, at a lower threshold of speed).

Not sure how it might be possible to do so, but if you can manage to try out different (fairly new) tyres at different pressures, you just might find close to what you seek from the suspension (for a balance between ride and handling needing some fine-tuning/re-balancing - pure handling is a different matter). Tyres too, in a sense, form an important part of the suspension. There is much which goes in from a manufacturer to tune a suspension, and it is done with a certain tyre characteristics, including tyre pressure.

If for some reason one must reduce tyre pressure, I guess tyres with 2 ply sidewalls would help a bit.

In many cars, a 3psi reduction might not be a big deal for casual city drives, but some cars are more sensitive to tyre pressure changes (an indication that their suspension are tuned with a lesser margin of error - my Optra Magnum was such: I would overinflate the front by 2psi to improve steering response, and due to my overall use-case).

[itwasntme]

Originally Posted by Poitive

Underinflation in particular can be dicey; especially in more extreme use (planned or finding one's self in a near accident situation)

Very well said, thank you. To add, the Octavia TSI steering is very light (at least on stock size) and feels ultra sensitive to tyre pressures. No wonder that the 60 profile + 29 psi was making it feel even more wallowy and vague.

Stick to recommended pressures please!

[evil_grin]

Originally Posted by Poitive

Underinflation in particular can be dicey; especially in more extreme use (planned or finding one's self in a near accident situation) :

Thanks for the detailed explanation and looking out for me. Like you said, the points apply more strongly at extreme situations.

Manufacturer recommendations are just that, recommendations. Like you said, they are a good reference point to play around. Some want higher efficiency, so inflate higher. Some want better ride so they deflate.

Also, manufacturer recommended pressures have kept going up over the years. Earlier 28 psi was normal. Now we're seeing more than 34 psi. I suspect it's because of stricter efficiency demands of either govts or buyers and not because they are the optimum values for the car.

Originally Posted by itwasntme

Stick to recommended pressures please!

I'll stay around those values now. But I'll always choose a value that works for my requirements.

[badri13nath]

Originally Posted by sunikkat

I will raise both my hands and scream for ‘Bilstein B6’. My Octavia TDI is running on B6 since 18 months, and that’s the mod that I love the most, more than remap.
======
From the feedback that I heard on B6, it is durable and will outlive the car - hope that’s true.

Folks, My Octavia TDI (2016) too is due for an upgrade and have been deliberating for a upgrade for a while. Basis this thread, i am convinced that i need to consider ‘Bilstein B6’ as well. However, not sure on where and whom to reach for the same in Bangalore, any guidance from guru's in this forum.

[vignesh.cv]

Another suggestion: I went through a similar exercise on my car (2013 Laura TDI) a few years back. The default answer given by most is to change the dampers to the Bilstein B6 or better variants. While it does offer taut damping, I found that to be overly stiff for our kind of roads where the undulations are prevalent. If you are driving solo mostly & are okay with that feeling, then go ahead for it.

The other option would be to source from the OE parts bin - especially the European variant of the same car. I went down this route and I'm quite happy with the balance between firm damping and the plushness of the ride over undulations. Combine that with the right springs, you will have a machine with excellent highway manners as well as have a comfortable ride in city roads. Tune O Tronics helped me with the selection, sourcing of parts & installation.

[sunikkat]

Originally Posted by badri13nath

Folks, My Octavia TDI (2016) too is due for an upgrade and have been deliberating for a upgrade for a while. Basis this thread, i am convinced that i need to consider ‘Bilstein B6’ as well. However, not sure on where and whom to reach for the same in Bangalore, any guidance from guru's in this forum.

I got it from Pete’s Cochin as they are the official dealers for Bilstein in India. But I am sure guys at Engineering Exponent, Code6 etc in Bangalore can source them too.