205 Gentry V6 And Its Rear Suspension

[Tesstuff 222]

We have pretty much sorted the front suspension on my v6 conversion and now the attention moves to the rear.

 

There is an element of understeer apparent now with the extra weight up front of the v6, but I drive it accordingly, so my question is what are the options to get a good turn in back again?

 

I am not expecting it to ever be as sharp and precise as the 205 Gti's, but I would like it to be as good as it can be, and I know at present with Gentry standard set up it can't possibly be that

 

After reading a fair few threads it seems I need to upgrade the standard Gentry torsion bars(17/18mm??) to something thicker, possibly the 21mm VTS items?

 

But would it also be a good idea to get a thicker rear ARB?

 

I have standard 205 Gti rear shocks at present, would a change there help out the end desire too?

 

After the changes I would like it to then be set up somewhere professionally and get optimum camber/toe in suggestions and changes.

 

I know there will be a lot of permutations on this subject but I would expect nearly all changes will improve matters, in whatever order they may come.

 

So to summarise, I have a standard rear Gentry beam which is the same as a Gti 1.6 beam, and it has had a recent reburbishment with all Pug parts so I am happy that is up to the task. It has the standard ARB and torsion bars and it is at standard height.

 

I run the 406 Coupe v6 alloys on 195/45/16 tyres.

 

Any help and suggestions are gratefully received.

[feb 47]

Thicker rear torsion bars and ARB will help reduce understeer.

[Anthony 1,002]

After reading a fair few threads it seems I need to upgrade the standard Gentry torsion bars(17/18mm??) to something thicker, possibly the 21mm VTS items?

I've not stripped one, but I'm assuming that a Gentry runs basically the same beam setup as an STDT, namely 18.5mm torsion bars and a 16mm ARB.

 

The combination of a boat anchor in the front and considerably stiffer VTS springs will certainly promote understeer with the existing rear setup, and how to go about fixing it I guess depends how much you're looking to spend. Simply swapping the TB/ARB's for GTi 19mm items (assuming it isn't that already) won't fix but should improve matters slightly. Beyond that, an uprated ARB will improve turn-in and is comparitively cheap to do, although ultimately you really want a pair of uprated torsion bars to balance the front and rear spring rates out. I'd guess something like 21mm torsion bars would be about right for balancing out the VTS springs.

 

You can't run VTS (or indeed other non-205) torsion bars as they're the wrong length, and there isn't enough meat on a torsion bar to cut them down and respline like you can with 306/Xsara anti-roll bars.

 

As you say, I don't think you're ever going to give a V6 the turn-in and balance that you can with a standard engine given the amount of weight and how far forward it sits, but you should be able to make a substancial improvement without completely ruining the ride quality.

 

Or you could just put a pair of space savers on the back and banish understeer forever

[Tesstuff 222]

Thank you for that reply Anthony, confirmed a few things, but also puzzled me too.

 

I thought the VTS 21mm torsion bars were a popular 205 upgrade yet not for my beam?

 

I have adjusted to the extra weight and change in turn in, and I am happy with it , but know it can be better, so I am just looking to make it as good as it can be.

 

Something like a 106 Gti ARB might be beneficial then.

 

[Anthony 1,002]

I thought the VTS 21mm torsion bars were a popular 205 upgrade yet not for my beam?

They're a popular upgrade for 306's rather than 205's

 

Something like a 106 Gti ARB might be beneficial then

Yup, that'll work - you'll need to use 306 end plates with it though, as 205/309 ones won't fit

[Alastairh 47]

Does it have a GTI spec front anti roll bar?

 

Al

[Tesstuff 222]

Anthony was it you selling much thicker torsion bars for 205's?

 

What is the usual way 205's get thicker torsion bars then?

[Tesstuff 222]

Does it have a GTI spec front anti roll bar?

 

Al

 

Good question, a lot has changed, have to ask.

 

You could always have looked for me when i nearly popped round the other day Al

[marksorrento205 80]

Daz, im 99% you have 18.5mm torsion bars on the rear as the gentry ones were reused

 

Edit: front arb is the original one too

 

Edit again it also has the 3 line brakes with the single compensator like the 1.6

Edited January 4, 2011 by marksorrento205

[Miles 331 1 Cars]

Yes Gentry's don't have GTi rear's only the Drums are to a point as they use a 4 line brake system, But I have seen 1 3 line system AKA 1.6 GTi so even a upgrade to the GTi bars would help allot, ARB's go for the largest one you can in my book, I run a 30mm bar on the 306 and it makes a huge differance.

Front ARB is the same as any GTi,

[Tesstuff 222]

Excellent reply Miles.

 

Do you notice any changes in the 309 v6 handling with the additional weight ?