M Series Hillclimb car

[Gnasher]

After competing in hillclimbs & sprints for 9 years, a couple of years in an S2 Vixen & 7 of them in my 3000S, I've decided to give the S a 'birthday'. That will include another body off, a repaint and returning it to a standard(ish) road car.

I've bought a very early 1972 1600M for the hills, and that's currently in lots of bits.
It had been in a garage since 1990, and was fitted with a 1600 Pinto engine which was the first thing to go. A 1690cc short engine from the Vixen is being rebuilt, and I've got a Rocket box to go with it.

I know that the M chassis & shell are heavier than the Vixen ones, except for S4 Vixens which use an M chassis. I'm trying to get as much weight out of the car as I can, but the weights quoted for a 1600M are confusing. Depending on which article or book you read the weight is quoted as being anywhere from 800kg (16cwt) to 881kg. My feeling is that it's nearer the 800 mark, but does anyone know better? I know I won't get down to the 715kg my S2 was, but every little helps.

By the way as part of this project I am both looking for some bits, passenger seat, perspex rear screen, exhaust manifold & system, and looking to sell some other bits, dashboard, console, Powrlok 3.54 diff, 2000E & V6 gearboxes, rear disc setup, rear antiroll bar amonst other stuff. I will be putting them on Pistonheads classifieds when I get round to it, if anyone's looking for anything

SteveD

[madsvlund]

Hi Steve

Sure you can get it down a bit. I have a scale in my crane, and did weigh all my components for my 3000m duratec V6

Chassis with aditional beams and suspension is 100 kg
duratec V6 with gearbox is 170
Diff is 45 kg
driveshafts, exhaust, radiator, brakes and other small bits is 60 kg

Total roling chassis is 375 kg (200 front 175 rear)

wheels 80 kg
cabin with seats windows ex doors is 200 kg
bonnet + doors (est 90 kg)
fluids, battery and various bits 30 kg

So I expect to be just bleow 800 when finished

And there are plenty of places to save, rear window, isolation, seats, bonnet, diff, brakes, fuel tank, battery, flywheel
So 725 should be within reach

Br Mads

[Gnasher]

I know what you mean, the original bonnet, with frame & lights was 90kg, the one I am using is 60kgs, so there's 30kg saved.

I'm trying to save a bit of weight on everything, for instance the original TVR crossflow radiator, I don't know what it weighed because it fell to bits as I took it out, but the replacement one is alloy fins with plastic tanks, as used on Caterfields & weighs very little, I've got an 8kg drivers seat, the heater rad is going, perspex rear screen & windows, with no winders or door trims, etc etc.

I think 725kg will be too optimistic, the rollcage is fairly heavy but we'll see.

SteveD

[TVR_owner]

I'm aiming for 790 post rebuild Steve, that's with full cage and cast block and heads Essex.

They can loose weight better than us humans, and keep it off!!

[dryden]

And a factory lightweight shell..!! ............If ever there was such a thing...............

[TVR_owner]

dryden said:

And a factory lightweight shell..!! ............If ever there was such a thing...............

There was. Why would you challenge?

[dryden]

Hi John,......Not callenging!, Said with a wink..... but, During the prodsport days when I could not catch Chris Meek in my Vixen, I consoled myself that His Car had a lighter shell,.............In truth I could not catch anyone much, but that is not the point...........I spoke to Chris one depressing day at Brands, and he laughingly said he did not think the shell he had was any different, I took that to mean that oficially, factory lightweight shells did not exist in PRODSPORTS.

[TVR_owner]

Sorry Clive, took it the wrong way. My car is an ex factory prodsports car and the shell is very light. I suspect Chris would not know how different his car was from a road car, but I'm sure he would know it was close to not very legal .

[dryden]

Yes, I remember your car, coming at me in my mirrors with headlamps blazing, and STEWART writ large on the bonnet, lapping me!!......................I consoled myself with the fact that he had a lightweight shell and an essex!!

[Gnasher]

Hi John,

So, with a Crossflow, Rocket box with alloy bellhousing, Vixen diff & half cage, minimal trim & pespex on the side & back, getting well under 800Kg would appear easy. I was suprised how much the 45's & manifold weigh.

The original bonnet with frame & lights was 90kg! I've replaced that & saved about 30Kg. I thought that was good, but talking to the Vixens at Harewood just highlighted the difference between Vixens & Ms. A standard Vixen bonnet weighs about half as much as my new one.

SteveD

[TVR_owner]

Steve,
Sub 800 should be possible as long as the shells not had heavy repairs?

easy weight savings with aircraft quality fittings and correct length bolts. Correct size cooling systems also can save a few kilos?

All mention of drivers weight should be ignored..

[Gnasher]

John,

As I'm sure both myself & IanB have pointed out previously, in the TVRCC Speed Championship handicap is based on power & car weight, NOT including driver.

Having said that handicap isn't everything, and getting the weight down makes beating those 4 & 5 litre cars on scratch up Harewood that bit easier.

SteveD

[TVR_owner]

Gnasher said:

John,

As I'm sure both myself & IanB have pointed out previously, in the TVRCC Speed Championship handicap is based on power & car weight, NOT including driver.

Having said that handicap isn't everything, and getting the weight down makes beating those 4 & 5 litre cars on scratch up Harewood that bit easier.

SteveD

I was never sure Steve on the PTW handicap, where I was coming from was that whenever discussions started relating to loosing car weight, there was always an inference (often those close to us....) that driver weight loss was cheap, necessary, and would result in funding being diverted from beer purchase to car prep