Battery Relocation

TVR Battery relocation is always a fiercely debated subject. The standard location is in the passenger footwell along with the ECU and fusebox. Although some will argue that this is the best place, in the Griffith passenger leg room can be described as woeful at best. My second motivation for looking into relocation is to tidy up the mess in the footwell and to allow easier access to the fusebox and ECU.

Existing battery location

The OEM battery is a standard lead acid type 072.

072 Battery Specifications
AH Value 70
CCA 570
Reserve Capacity 125
Length 261mm
Depth 175mm
Height 220mm
Weight 18.4 KG

A popular battery relocation option and one that a number of TVR owners have opted for over the years is to fit a single Odyssey PC925 battery in the boot of the car. Speaking to owners who have fitted this battery, all have been very pleased with the result long term and have not had any notable issues.


Odyssey PC925 Specifications
AH Value 28
CCA 330
Reserve Cap 27
Length 168mm
Depth 179mm
Height 148mm
Weight 11.8 KG

Odyssey batteries are widely regarded as one of the best batteries available and have various advantages over traditional types of battery:

Cranking power – capable of providing engine cranking pulses in excess of 2250 amps for 5 seconds, double to triple that of equally sized conventional batteries
Longer service life – up to 10 years of service life
Longer cycle life – 70% longer cycle life than conventional deep cycle batteries
Faster recharge – The highest recharge efficiency of any sealed lead battery on the market, capable of 100% recharge in 4-6 hours.
Mounting flexibility – Non-spillable design, can be mounted on any side in any position except inverted.
Vibration resistance – Design protects against high impact shock and mechanical vibration, a common cause of premature battery failure.
Extreme temperature tolerant – Operating temperatures from -40°C to 45°C
Small footprint – flat plates made of 99.99% pure lead, not lead alloy. Pure lead plates can be made thinner.

Relocating the battery in the boot is great from an accessibility point of view but the issue for me is the fact the battery is located next to the fuel tank. While I accept that you do not buy a TVR for its safety credentials, personally I am not entirely comfortable with potentially introducing additional risk if it can be otherwise avioded. The chassis of the Griffith does not extend much past the rear wheels which leaves the boot area of the car protected only by fibreglass in the event of a rear end shunt as can be seen in the picture below:


In search of other solutions I turned the PistonHeads TVR community to see what other owners had done with theirs. As always lots of assistance and ideas came flooding in. I did see a number of Chimaera owners who had created a custom compartment behind one of the seats out of fibreglass which looks like a great solution. Unfortunately in the Griff I needed to retain access under the whale tail to access the bolts which secures it in place.

There was one suggestion from fellow Griff owner Frank (eff eff) who had done something I had not seen before. Frank had two smaller Odyssey batteries wired in parallel, one fitted behind each seat. What a liked about the design was not only were the batteries safely stored within the passenger compartment, away from the fuel tank, but the weight was evenly distributed.  I decided this was the solution for me so I contacted Frank who very kindly shared the specification of his install with me so I could replicate this in my car.

My solution, heavily based on Frank’s design is as follows:

2 x Odyssey PC680 wired in parallel (same voltage but double the AH value). This results slightly higher AH and CCA values and almost double the reserve capacity figure of the tried and tested single PC925 solution.

Odyssey PC680 – Single
AH Value 16Ah
CCA 170
Reserve Cap 24mins
Length 184mm
Depth 79mm
Height 191mm
Weight 7KG

Odyssey PC680 – Double
AH Value 32Ah
CCA 340
Reserve Cap 48mins
Weight 14KG

Regarding the hold down kit, the official kit from Odyssey would not fit in the area behind the seats so I needed to source an alternative with a smaller foot print.

Odyssey Hold Down 2.jpg

After some searching on the internet I found a lightweight billet hold down kit from an American company called JPUSA. The hold down kit had a footprint only slightly larger that the PC680 battery itself.

Billet Hold Down 1.jpgbillet-hold-down-2

I understand from owners of TVRs equipped with the PC925 battery that the battery must not be allowed to run flat (under 10.5v) as the battery cannot be revived. Running the battery flat is not normally an issue for me as generally the car is attached to a trickle charger when not in use. I have run my existing battery flat a couple of times down to my own stupidity (leaving lights on etc). Due to the reduced reserve capacity of the Odyssey batteries vs the OE 072 battery I decided it would be a good idea to fit a battery monitor in the form of Battery Brain. A Battery Brain is a compact battery monitoring device that continually monitors the battery charge. If the charge to drops below the minimum required level (11.8v) to start the vehicle, it disconnects the battery. Not only does this stop you getting stranded it also protects the battery from becoming fully discharged. I decided to purchase the battery brain with the IR remote disconnect fob just in case I need to leave the car for a long period of time I can remotely disconnect the battery after I have locked the car.


I asked Jody at Python Racing to complete the conversion while the car was in having its annual MOT completed. As per usual Jody did an excellent job and I am very pleased with the end result. I will arrange for the trimmer to fit an extended piece of carpet in the passenger footwell and possibly carpet over the batteries in the near future.


I also purchased a new trickle charger for the car as part of this upgrade. I was unsure as to whether my Accumate trickle charger was compatible with AGM Gell batteries. To be on the safe side I purchased a new CTEK charger with an AGM battery mode.



Snetterton 300 Track Day


Another Snetterton track day organised by fellow TVR Pistonheaders. One of my favourite tracks as it is less than 2 hours away from where I live and it suits the Griff being a power track with long straights.

The circuit for the track day was the full 3mile ‘300’ circuit which includes 2 fast straights and a number of more technical areas.

The noise limit for the day was 105dB static. Last year I just sneaked through the limit without the need for any additional cans. This year the same, the car was measured as 104dB much to the surprise of the MSV staff. On track unfortunately I I was black flagged as I breached the driveway noise limit and was required to don the ACT bolt on silencers.

The weather forecast was grim but the rain did not come in the quantity that was forecast so for the most part the track was dry. The TVR performed impeccably.

As per usual my trusty GoPro was on hand, unfortunately MSV deemed that the official 3M GoPro mount was no longer allowed for trackdays and all cameras needed to be mechanically mounted so I was not allowed to run with the camera on the front of the car.

I was also running Harry’s Lap Timer app on my iPhone, not for competitive lap timing as this is not allowed but for video telemetry overlay on my personal videos.

I have also invested in a Racelogic VBox Sport to use with Harry’s Lap Timer as the iPhone internal 1Hz GPS sensor proved did not seem to adequately keep up with the video before. The Racelogic VBox has a 20hz GPS sensor and pair with the iPhone using bluetooth. You can see it Gaffer taped to the dashboard in the video.


My best lap of the day was 2:24.66 at an average speed of 73.8MPH which I was happy with.





TVR Power Dyno Run


I booked the Griff in with Powers Performance (TVR Power) for a dyno run following my last visit to the drag strip for PH Sunday service. My 1/4 PB is 13.202 a couple of years ago, I have since changed the standard cam for a TVR Power 885 cam and the road tyres have been swapped for AD08Rs.

Sunday service was great fun but I could not get any faster than a 13.5 and my terminal speed was down from 107 to 104. My assumption was the car had lost a bit of power somewhere so I booked the car in with Jason at TVR Power.

To my suprise the car was up from 242.8BHP on the original TVR435 cam to 275.1BHP on the TVR Power 885 cam. Torque also looking more healthy up from 278 to 295. Clearly no horses have bolted the stable so clearly down to the driver :-/ perhaps I have lost some driver XP

TVR Power dyno reads in wheel BHP so I have converted to flywheel using the below site

BHP – 324BHP
Torque – 348ftlb

A huge thank you to Dom and Jason at TVR Power not only for accommodating me a short notice; despite using up over 2 hours of Jasons time and using the dyno cell Dom refused to take any money from me. A very kind gesture and I am most grateful.



Jason showed me some of the work he has been doing with the MBE ECUs which I am now 100% set on getting fitted to mine. Really nice pieces of kit and used by the likes of Caterham, Noble and Harley Davidson so fully type approved and OEM quality. Mine randomly lost all power last weekend, a quick rummage in the foot well and order was restored I think I am on borrowed time with my loom, it has already been repaired twice at great expense, looking at the quality looms Jason makes up for the MBE systems I am convinced this is the way to go.

The Griff did well against the M5s at Sunday service:

What I cannot work out is if I have a mildly tuned 500 with 275BHP at the wheels, how does a completely standard 500 leave me for dead mid track onwards despite getting a good start?

In summary TVR Power = awesome. TVR Power 885 cam = awesome. Driver needs lessons. How the F*** is Dave’s Griff so quick?

T5 Gearbox S10 Tail Housing conversion

Before I begin I must mention David Byron to thank him for his assistance and guidance with this modification.

All TVRs from late Griffith onwards use the Borg Warner T5 gearbox. Griffith and Chimaera used an earlier tail housing for the T5 box which required an additional linkage to bring the shifter out in the correct place.



On the later ‘T’ cars TVR used the S10 tail housing which presented the shifter in the correct place and did away with the additional linkage.



The basis of this modification is to retrospectivily fit the later S10 tail housing to the T5 gearbox in my Griffith, thus deleting the additional TVR linkage and improving the feel of the gearbox. I also opted to complete a number of other small enhancements along the way.

John Reid at Readman Racing (Grantura Engineering) has been offering this upgrade for a while and supplies reconditioned S10 tail housings with a new top section with all new bushes and the new selector etc so that the two complete units can just be swapped straight over. From speaking to other owners who have completed the modification a new mount for the gearbox is required and also the TVR remote linkage offsets the gear lever by about 2 inches toward the driver so a dog leg needs to be introduced into the shifter to present it in the same position as before.

As part of the S10 package I also purchased a bronze shift cup and bronze shift forks to replace the standard plastic items again supplied by John Reid.


I also opted for a replacement Hurst shifter with improved pre-loading to make shifting from 2nd to 3rd easier. I purchased a custom Hurst shifter from Core Shifters built specifically for S10 T5 boxes and with a custom fulcrum height designed for the 6 inch TVR stick.


Finally I decided upon a custom Stainless Steel gear knob from Chris at Lathewerks in the USA. Machined from a solid block of steel and weighing in at 550G it is approximately 3 times heavier than the original TVR item and has a slightly bigger circumference.


David Batty my TVR specialist has completed the modifications to the gearbox while changing the clutch and replacing the leaking rear main oil seal.

First impressions are good, it is now easier to select gears at the far end of the box (5th and reverse). The Hurst shifter has reduced the distance between the gears slightly and has a more positive self centering effect. I will update this once I have done over 1000 miles to get a feel for it.

1000 mile update – I have since completed a RWYB day at Santa Pod, a number of long 300+ journeys and a track day at the Lotus test track. I am pleased with the improvements to the gearbox and definitely worthwhile if the box is coming out anyway, I would personally not recommended spending the money on labour removing the box just to have this mod done. The difference is not night and day different just subtly improved.


Castle Combe Track Day

Castle Combe

Another fantastic track day made even better by great TVR friends. I was in two minds whether to book this up as it is a bit of a trek for me but glad I made the effort. It was an early 04:30 start for me but the traffic was good and arrived at 08:00 for the briefing.

The briefing was interesting, I made particular note of Quary being the most crashed corner of any UK track so the advice given was brake before the hill, neutral throttle over the hill and then brake further once on the correct line on entry to the corner. I never quite mastered it but the car is still in once piece so that is a bonus.castle-combe-track-layout

I opted straight for the instruction which Peter managed to negotiate into the price of the day when he booked the group. The instructor was very helpful and showed me lines and gave me lots of useful tips.

Driving around the track you cannot help but notice the barriers are very close and no run off or gravel traps whatsoever. Clearly not a circuit where you can take the piss.

Peter also very kindly took me out in his car 5.5 litre Chimaera I must say I am very impressed with his new cam it ‘feels’ much faster that it did before, must be the extra torque.

Phil managed to capture some footage from the pit wall and kindly sent it to me.

The combination of instruction and going out with Peter by the afternoon I had a bit more confidence and was pushing the car harder I had a great run with the Porsche Cayman which pulled me through to my fastest time of the day 1:28.88.

The AD08R tyres continue to amaze me, manged to get up to 1.2G this time. Once you have heat in them they do not seem to let go.

Castle  Combe

Bit of analysis from Harry’s Lap Timer:

Castle Combe

Great to see and catch up with Anthony Precat as well, we had a great run back and was enjoying watching the epic flames from his stunning Griff.

Castle Combe

Bedford Autodrome Track Day

Bedford Trackday

First track day of the year, Bedford Autodrome and I am keen to test out my new Yokohama AD08R tyres and new geometry setup. The track was configured as the full 3.8 mile GT circuit.

011 Bedford

A few laps in and I am very impressed with the new tyres, once they have heat in them they stick to the track very well indeed. I found that I was able to corner much faster with the new rubber and they did not overheat like the old Toyo T1Rs did. The car felt really good with the new geo and the test Tuscan seat I have fitted is great on a trackday when you take the cushion out.

Bedford Trackday

I had an opportunity to test out my new GoPro 4 Silver which I purchased earlier on in the year as my old GoPro Hero HD was starting to play up. Video quality is much improved and the screen makes it very easy to line up camera. I also had an opportunity to test out Harry’s Lap Timer for telemetry, I had used this previously at Brands but that day was a bit of a wash out. The Telemetry showed a GPS verified 145MPH down the back straight which I was impressed with. Also a nice graph of the track with speed and G-Force overlayed

Bedford Trackday

Bedford Trackday

Here are some videos from the day:

Session 1

Final Session – chasing an Exige, unfortunately the Lotus spins off

Harry’s Lap Timer Test

Dashware Test

Ian’s Griff

Chris’s Clio

My car behaved itself for most of the day aside from needing to bump started by kind folk from PH every time I wanted to go out on track. The issue appears to be the infamous hot start issue, I did have this before and it was solved with my new Carl Baker meta alarm system installation, the general consensus was the wire the starter motor needs to be uprated as this only happens when the car is really hot, i.e. trackdays.

The car also developed another issue which was driving me mad, I had a feeling that the car was getting slower each time I took it out but I dismissed the idea as me being stupid. Half way through the afternoon session I came to the realisation that there was definitely something wrong as I was using full throttle and getting no where. It turns out that the throttle cable had worked itself loose. After consulting the PH technical committee I proceeded to dive head first into the footwell to look at the issue, luckily it was only the screwed on nipple which had come loose and I managed to fix it fairly promptly and continue with the trackday. Alun of course had to take a picture!

Bedford Trackday

Snetterton Track Day

Griff Snet

Seeing as a had such a good time at the Snetterton track day last year I decided to join my fellow TVR Pistonheaders on the Autumn Snetterton track day and at a very reasonable early booking price of £129 for all day Open Pit Lane.

The circuit for the track day was the full 3mile ‘300’ circuit which includes 2 fast straights and a number of more technical areas.

The noise limit for the day was 105dB static. Last year I just sneaked through the limit without the need for any additional cans. This year the same, the car was measured as 104dB much to the surprise of the MSV staff.

With the briefing and sighting laps out the way I waited 30 minutes for the initial rush to settle down and went out on track. The weather was fantastic and the track was bone dry. I managed to get through almost 2 tanks of fuel so a good day was had and the TVR performed impeccably.

As per usual my trusty GoPro was on hand and my friend had also lent me his so I was able to mount one to the front of the car and the other on my headrest mount had two mounted to the car. The first half is probably my tidiest lap. The second half starts with a rather ambitious overtake which ends up with me on the grass.

Direct Link: http://youtu.be/SCnGH-pc3p4

A great day out and good to catch up with the usual TVR track day goers. I must look at replacing my tyres with a more track friendly compound when they are due as my Toyo T1Rs are great on the road and in wet conditions but seem to overheat on track. I have either some Toyo R1Rs or Yokohama AD08Rs in mind.

Griff Snet 2

Griff Snet 3