Have I improved over 5 years ?

[hoffman900]

I don’t agree with the stiffer spring / smaller bar approach at all, and absolutely believe in the opposite. 
 

Soft springs, big bars, and the best shocks you can afford. 

[Hamish]

4 hours ago, hoffman900 said:

I don’t agree with the stiffer spring / smaller bar approach at all, and absolutely believe in the opposite. 
 

Soft springs, big bars, and the best shocks you can afford. 

When you say big bars ? Is this referring to rear arb ?

As can be seen from this forum I am a novice and a spanner man rather than an inventive fabricator - i think you are right if I had fully independent set up. But I don’t. I have a girling axle that is above the chassis lever shocks and leaf springs. Thus, I think, I don’t have the movement deltas to go too soft. 
the likes of revington I’m sure wouldn’t have the hard spring options for these cars if they were wrong. 
 

but would love to learn more from you all. 
as you know apart from spannering I’m just the weasel behind the wheel !

Edited October 30, 2023 by Hamish

[Escadrille Ecosse]

6 hours ago, hoffman900 said:

I don’t agree with the stiffer spring / smaller bar approach at all, and absolutely believe in the opposite. 
 

Soft springs, big bars, and the best shocks you can afford. 

That is the Colin Chapman approach along with careful control of tyre contact patch that has basically been adopted by pretty much everyone over the years and - along with advances in tyre technology - has given us the huge improvements in grip, handling and ride quality of modern road cars.

But soft springs require long travel to keep the car off the bump stops or you're visiting the foliage big bars or not. And that long travel needs to be designed in from the start. Along with clever anti-dive and anti-squat geometry to handle the braking and acceleration loads that the soft springs can't. 

Unfortunately TRs with their underslung chassis and short travel suspension were designed from a different era.

And we're also talking here about track suspension on generally better surfaces and in those conditions I go with the Alan Stainforth approach for track cars (as opposed to road cars) that it's the springs that do the work and light roll bars are used to trim the handling.

Regards shocks. Early TRs are also rather constrained in that getting away from lever arms at the back is very difficult/expensive.

Mr Stainforth's advice for has worked exceptionally well for my Spitfire on the track, but I'll not argue about it.

Regards springs, agree with Nick about Faulkners for coils. Excellent company. 

No personal experience of Owens but definitely worth a chat about those mono leaf springs 

PS. I had a search and Flex-Form appear to be still in business. Might be worth an equiry http://flex-form.com

Edited October 30, 2023 by Escadrille Ecosse

[Escadrille Ecosse]

The late, great Alan Staniforth. Legend.

On the subject of car prep I cannot recommend this book highly enough even if much of it is beyond the scope of racing old stuff his explanations of the principles are superb and applicable to our cars.

It is out of print now but you can still get hold of second hand copies. He has a couple of others too, Competition Car Suspension and High Speed Low Cost (which is older and even more of a collectors item).

 

[Hamish]

Thanks just ordered a 2013 edition. 

[hoffman900]

3 hours ago, Escadrille Ecosse said:

That is the Colin Chapman approach along with careful control of tyre contact patch that has basically been adopted by pretty much everyone over the years and - along with advances in tyre technology - has given us the huge improvements in grip, handling and ride quality of modern road cars.

But soft springs require long travel to keep the car off the bump stops or you're visiting the foliage big bars or not. And that long travel needs to be designed in from the start. Along with clever anti-dive and anti-squat geometry to handle the braking and acceleration loads that the soft springs can't. 

Unfortunately TRs with their underslung chassis and short travel suspension were designed from a different era.

And we're also talking here about track suspension on generally better surfaces and in those conditions I go with the Alan Stainforth approach for track cars (as opposed to road cars) that it's the springs that do the work and light roll bars are used to trim the handling.

Regards shocks. Early TRs are also rather constrained in that getting away from lever arms at the back is very difficult/expensive.

Mr Stainforth's advice for has worked exceptionally well for my Spitfire on the track, but I'll not argue about it.

Regards springs, agree with Nick about Faulkners for coils. Excellent company. 

No personal experience of Owens but definitely worth a chat about those mono leaf springs 

PS. I had a search and Flex-Form appear to be still in business. Might be worth an equiry http://flex-form.com

I still disagree with this approach. 
 

We’re running on big fast, smooth tracks in the US (as well as some tighter club tracks) and the soft spring / big bar approach is absolutely the way to go, especially as curbing has increased in width. You can get the entire car out on the rumbles and basically expand the track by 5-6ft in places. On corner entry and the apex you can buy yourself a foot or more as well to the inside.

Almost every modern racing chassis is a soft spring / big bar approach for this reason. 
 

That said, this is all rules dependent. In US vintage racing, it’s based off the 1967 or 1972 SCCA GCR (depending on run group) with some slight allowances. However, the SCCA rules allow a few things;

* tube shocks in the read

* axle locating devices can pass into the cockpit. 

* shocks are free as long as they don’t have remote reservoirs
 

This means in the rear, you run a 3 link set up with spring rates around 100-125lbs-in (on a car like a TR, MGB, and anything else with similar weight), with a rear anti-roll bar and a panhard bar. The fast MGB racers are using revalved lever shocks in the rear (for reference, our fastest MGB competitor has turned 2:17s at Watkins Glen vs the Triumph TR250k which has done 2:19s, we’ve gone 2:17 flat (with room to spare) in a TR4). Rear spring rates on both were in the 125lbs-in neighborhood. Working on another car that is faster than both of those, but similar wright, and we’re even lighter on the rear spring. 
 

On the front, you get the travel by modifying the spindle. What you can do, and is legal here, is to move the spindle up (effectively buying you an inch without losing travel) as well as extend the kingpin up, making for a slightly taller upright, and improving camber gain. This is a pretty common modification across several makes / models at the front of the pack here.  
 

Shocks are free here except no remote reservoirs. To run at the front, you see some very expensive Penske, Ohlins, or Koni’s, as they have non remote reservoir shocks that are still a very high level. Again, these help immensely with FIA type curbing / rumble strips. 

[JohnD]

Returning to Hamish's original post, I cannot hope to better his excellent comparative videos! But I have kept records from when I first started racing.   The venues have changed, for instance, I haven't been to Lydden or Pembrey for a long time, but  I did do Donnington in my first year and the last time was 2017.  My best lap times were comparable, I think, because Donnington never includes the Melbourne Loop in Club racing (AFAIK):

1994 - 1:50.29

2017 - 1:39.1

So, in thirteen years, I have improved by ten seconds!

JOhn

 

Edited October 30, 2023 by JohnD

[Escadrille Ecosse]

5 hours ago, Hamish said:

Thanks just ordered a 2013 edition. 

Good stuff Hamish.

@hoffman900 I am always impressed by the stuff that goes on in the States regards classics racing and have borrowed some ideas from you gentlemen from time to time. However the type of competition here and in particular the type of competition in which Hamish and I partake is fundamentally different. We're comparing apples with Tuesday here a lot of the time.

For riding deep into rumble strips then absolutely having as soft a spring as possible is a must. But most of our tracks don't have them and where they are there they are maybe only a foot wide and more like actual raised street kerbs so running up them gives no real advantage. Plus using them for advantage is against the rules.

This for example is Hamish at Harewood, which is a comparatively open track.

Others like Shelsley Walsh or up my way Doune in Scotland are even more enclosed. OK it's a single seater but gives you the idea. Keep all four wheels very much on the black bit at all times. And see the size of the one rumble strip.

Also a lot of the mods you are permitted are not allowed for us unless you want to get put in with the Modsports guys!

And then there is a very different driving style due to the type of event with more and more severe changes in speed, gearchanges, etc. where low speed traction comes more in to play (greased weasel territory).

So horses for courses really. Yes there are a couple of sprint courses like Curborough in the opening video which has a particularly bumpy right hander where a softer setup might actually help, but overall not so sure.

2 hours ago, JohnD said:

So, in thirteen years, I have improved by ten seconds!

But starting off from a decent position I would say that is pretty decent.

Edited October 30, 2023 by Escadrille Ecosse

[JohnD]

Still not winning, though usually midfield not dead last. 

Except in CSCC Sw.60s Goup2, where the competition includes 5 Litre TVRs and Sunbeam Tigers, and E-types, when I a often, again, dead last!  But I have to admit, the front runners include TR6s, so there is hope!

Jphn

[hoffman900]

11 hours ago, Escadrille Ecosse said:

Good stuff Hamish.

@hoffman900 I am always impressed by the stuff that goes on in the States regards classics racing and have borrowed some ideas from you gentlemen from time to time. However the type of competition here and in particular the type of competition in which Hamish and I partake is fundamentally different. We're comparing apples with Tuesday here a lot of the time.

For riding deep into rumble strips then absolutely having as soft a spring as possible is a must. But most of our tracks don't have them and where they are there they are maybe only a foot wide and more like actual raised street kerbs so running up them gives no real advantage. Plus using them for advantage is against the rules.

This for example is Hamish at Harewood, which is a comparatively open track.

Others like Shelsley Walsh or up my way Doune in Scotland are even more enclosed. OK it's a single seater but gives you the idea. Keep all four wheels very much on the black bit at all times. And see the size of the one rumble strip.

Also a lot of the mods you are permitted are not allowed for us unless you want to get put in with the Modsports guys!

And then there is a very different driving style due to the type of event with more and more severe changes in speed, gearchanges, etc. where low speed traction comes more in to play (greased weasel territory).

So horses for courses really. Yes there are a couple of sprint courses like Curborough in the opening video which has a particularly bumpy right hander where a softer setup might actually help, but overall not so sure.

But starting off from a decent position I would say that is pretty decent.

Here is one of our competitors on one of our usual tracks. Note after his spin how much track he is using to catch back up. The car is a 1622cc (MGA) Elva Courier, also set up like I mentioned. 
 

Lap time wise it is a good 2-4” / lap faster than the fastest Triumphs at this year’s Kastner Cup (including the TR250k) A great TR4 can run this fast, but the fastest one in the US retired from racing and the car is in the garage. We run an Alfa GTV that is another 3” a lap faster than the video car. 
 

A little different than what you guys run, for sure. 

[Escadrille Ecosse]

Thanks. Nice video. That Elva is a quick little car. And a pretty ballsy driver too. I watched him going for that move that led to the spin thinking wow, confident. Then the spin

Interesting watching the tussle with the Lotus. The driver of that car looked a lot less smooth but the car seemed very much more forgiving.

Those are big rumble strips, and the flat concrete beyond them on the outside of some of those corners. See what you mean by what can be gained. Not sure though that taking the harsher kerbs on the inside was actually beneficial as it seemed to unsettle the car quite a bit and felt to me that it would have been better avoiding those. But then I'm just looking at the video and not feeling it from the car. Which is a whole different thing.

I take it that green Spyder isn't yours?

 

[hoffman900]

We’re not out there in that session. The GTV we run is a few seconds a lap faster, but that car is tough on a tighter circuit. It’s driven how these cars should, it is a race after all. The Elan should be MUCH faster.