Silverstone Track Day
- Mad Mart
- TDC Member
- Posts: 8535
- Joined: Tue Oct 03, 2006 5:48 pm
- Location: Winscombe, North Somerset, England
- Contact:
Bloody excellent Dave!
I'll have to give a bit more detail tomorrow as I'm absolutely knackered. Got up at 4:45am, left home at 5:30am. Got back at 19:10pm. Then I had to go Bowling.

I'll have to give a bit more detail tomorrow as I'm absolutely knackered. Got up at 4:45am, left home at 5:30am. Got back at 19:10pm. Then I had to go Bowling.

Sprintless for the first time in 35+ years.
... Still Sprintless.
Engines, Gearboxes, Overdrives etc. rebuilt. PM me.
2012 Porsche Boxster 981 S


Engines, Gearboxes, Overdrives etc. rebuilt. PM me.
2012 Porsche Boxster 981 S

- Mad Mart
- TDC Member
- Posts: 8535
- Joined: Tue Oct 03, 2006 5:48 pm
- Location: Winscombe, North Somerset, England
- Contact:
As I said it was a great day, well organised & the weather stayed fine and my Sprint got me there & back in one piece (always a bonus).
After signing in and getting our numbers & wrist bands we had the usual pre-track briefing. The day was divided into three separate sessions; Lotus on Track had the first session with MGs on track taking the other two, ClubTriumph members mingled with the MGs. All sessions lasted 20 minutes and believe me, driving a circuit for 20 mins at a time is pretty knackering. I think it's more mentally tiring than physical.
The first session for everyone was to follow a pace car around the circuit for three laps at no more than 50 mph. The pace car would follow the racing line & the theory was that everyone would follow that line, but by the time it got towards the rear of the convoy...well lets say it's a bit like Chinese whispers. Anyway, that took up most of the first session but we did manage a couple of flying laps once the pace car pulled into the pits.
I found the circuit to be quite intimidating to start with as it’s quite wide & I felt a bit lost at times on that vast circuit of over 3 miles long. After the first proper session I was a bit disappointed as I felt, and probably was, all over the place, either braking too soon or too late & getting the race line completely wrong. But that was short lived. The next session I had learned by my mistakes & determined to get it right I was gradually carrying more speed through the twisties. What a contrast that session was to the previous & I got back to the garage with a big grin on my face. From then on it was pedal to the metal all the way, well quite a lot anyway. I did have a couple of moments; both at Vale. The first one I just out braked myself & had to run onto the grass, a bit bumpy but still, the second, after trying to keep up with the Herald estate that I’d let pass me a lap ago, I took the corner too fast & spun.
The best session was the last one. I lined up behind Jon Jackson (Sierra brake man) in his Sprint. It was brilliant, Jon was off like a bat out of hell & caught me napping but I soon caught up once he hit traffic. Then it was a case of scything through the slower cars (well actually, waiting ‘til they let us pass) MGFs, Midgets, even a Rover 75 V8 supercharged estate thingy (must admit, that V8 sounded awesome).
Ah! Well, back down to earth now, which reminds me, Life on Mars is just about to start.

After signing in and getting our numbers & wrist bands we had the usual pre-track briefing. The day was divided into three separate sessions; Lotus on Track had the first session with MGs on track taking the other two, ClubTriumph members mingled with the MGs. All sessions lasted 20 minutes and believe me, driving a circuit for 20 mins at a time is pretty knackering. I think it's more mentally tiring than physical.
The first session for everyone was to follow a pace car around the circuit for three laps at no more than 50 mph. The pace car would follow the racing line & the theory was that everyone would follow that line, but by the time it got towards the rear of the convoy...well lets say it's a bit like Chinese whispers. Anyway, that took up most of the first session but we did manage a couple of flying laps once the pace car pulled into the pits.
I found the circuit to be quite intimidating to start with as it’s quite wide & I felt a bit lost at times on that vast circuit of over 3 miles long. After the first proper session I was a bit disappointed as I felt, and probably was, all over the place, either braking too soon or too late & getting the race line completely wrong. But that was short lived. The next session I had learned by my mistakes & determined to get it right I was gradually carrying more speed through the twisties. What a contrast that session was to the previous & I got back to the garage with a big grin on my face. From then on it was pedal to the metal all the way, well quite a lot anyway. I did have a couple of moments; both at Vale. The first one I just out braked myself & had to run onto the grass, a bit bumpy but still, the second, after trying to keep up with the Herald estate that I’d let pass me a lap ago, I took the corner too fast & spun.
The best session was the last one. I lined up behind Jon Jackson (Sierra brake man) in his Sprint. It was brilliant, Jon was off like a bat out of hell & caught me napping but I soon caught up once he hit traffic. Then it was a case of scything through the slower cars (well actually, waiting ‘til they let us pass) MGFs, Midgets, even a Rover 75 V8 supercharged estate thingy (must admit, that V8 sounded awesome).
Ah! Well, back down to earth now, which reminds me, Life on Mars is just about to start.

Last edited by Mad Mart on Wed Mar 14, 2007 1:48 pm, edited 1 time in total.
Sprintless for the first time in 35+ years.
... Still Sprintless.
Engines, Gearboxes, Overdrives etc. rebuilt. PM me.
2012 Porsche Boxster 981 S


Engines, Gearboxes, Overdrives etc. rebuilt. PM me.
2012 Porsche Boxster 981 S

Standard Sprint diff is 3.54:1 Ratio
4.1:1 is a different ratio diff that will help the Sprint pull out of corner's quicker.
The downside is a slower top speed.
Not that you need much top speed on the track.
4.1:1 is a different ratio diff that will help the Sprint pull out of corner's quicker.
The downside is a slower top speed.
Not that you need much top speed on the track.
2011 Mini Clubman John Cooper Works. S Daily Driver.
1980 Dolomite Sprint with a touch of BLTS
Balanced Lightened and Tweaked 13B Rotary and SsuperCharged.
Back in my possession 22 September 2019.
Rebuilding the Sprint time taken so far, 111Hrs@15/12/2020
212Hrs @31/12/2021
352 @ 28/11/2022
455Hrs @ 20/10/2023
565Hrs @ 07/12/2024
This is time taken at the Sprint not necessary time worked.
Member TDC no 0471
Project 13B Sprint now back on..
No Pistons No Cams how’s it gonna Run Brap Brap?
1980 Dolomite Sprint with a touch of BLTS
Balanced Lightened and Tweaked 13B Rotary and SsuperCharged.
Back in my possession 22 September 2019.
Rebuilding the Sprint time taken so far, 111Hrs@15/12/2020
212Hrs @31/12/2021
352 @ 28/11/2022
455Hrs @ 20/10/2023
565Hrs @ 07/12/2024
This is time taken at the Sprint not necessary time worked.
Member TDC no 0471
Project 13B Sprint now back on..
No Pistons No Cams how’s it gonna Run Brap Brap?
.....
The ratio is the number of input turns to output turns of the differential. For example with a 4.11:1 when your prop shaft is turning at 4110 rpm your wheels will be turning at 1000 rpm. With a standard sprint diff when the wheels are at 1000rpm the prop shaft is only doing 3540 rpm. I won't go into the details of the engine to prop ratio except that in 4th gear it is 1:1; engine rpm = prop rpm.
So a lower ratio diff gives a more leisurely cruise as engine speed is lower for a given wheel rpm. A higher ratio makes the car accelerate better because you have lower gears. The difference between 4.11 and 3.54 is 14% We all know you change down a gear to get better acceleration to overtake someone. Marts car permanently in 14% lower gear than standard.
Hope that makes sense!
Tinweevil
The ratio is the number of input turns to output turns of the differential. For example with a 4.11:1 when your prop shaft is turning at 4110 rpm your wheels will be turning at 1000 rpm. With a standard sprint diff when the wheels are at 1000rpm the prop shaft is only doing 3540 rpm. I won't go into the details of the engine to prop ratio except that in 4th gear it is 1:1; engine rpm = prop rpm.
So a lower ratio diff gives a more leisurely cruise as engine speed is lower for a given wheel rpm. A higher ratio makes the car accelerate better because you have lower gears. The difference between 4.11 and 3.54 is 14% We all know you change down a gear to get better acceleration to overtake someone. Marts car permanently in 14% lower gear than standard.
Hope that makes sense!
Tinweevil
1978 Pageant Sprint - the rustomite, 1972 Spitfire IV - sprintfire project, 1968 Valencia GT6 II - little Blue, 1980 Vermillion 1500HL - resting. 1974 Sienna 1500TC, Mrs Weevils big brown.
I sit corrected
Tin

Tin
1978 Pageant Sprint - the rustomite, 1972 Spitfire IV - sprintfire project, 1968 Valencia GT6 II - little Blue, 1980 Vermillion 1500HL - resting. 1974 Sienna 1500TC, Mrs Weevils big brown.