Triumph Spitfire/GT6 weight list

[david langrick]

  My Car is a 1971 Spitfire Mk 4 with a 2,5 PI fitted moved back 6.5 inches
It has a Fibreglass Bonnet, front valances and bootlid.
It has a Saloon J type overdrive box , alloy engine back plate and Light steel flywheel -the new modern type.
It has minimal interior  with standard later seats, alloy  inner door panels . It has the Canleys alloy front hubs fitted.

car weight with soft top total was about  850 kg of which 460 was on the front wheels.
regards
Dave

[GT6 M]

Heres a few weights which show the GT is not that far off ideal.
well im talking mine, maybe others are diff.

I got moer weight than a standard GT.
Roto book says 2030 LBS with oil fuel tools.  922 KG
im on 2260 LBS with 5 1/2 to 3/4 gall of fuel   1027 KG
a diff of  230 LBS, or  105 KG

think this is frae
J type OD
2.5 crank
air horn pump
bigger discs
bigger batt
bigger water  bottle
15 inch wheels / tyres
F / R spoilers
thicker carpets
diff seats
loadsa under seal / waxy oil
oil cooler and pipes

BUTT, this is intresting, got car on weigh bridge the day, an did a total, and a 50 / 50 one.
this wid middle of wheel base on the scales end.

total weight is     1027 KG   2260 LBS   with  5.5-5.75 gall fuel
frunt weight is      563        1240
rear                    464        1021
nose heavy          100         220

So with a driver/ passenger, the weight  F/R would be about 50 /50
as yer sitting behint the middle if car,  or driver and a full tank same !!!

BUTT also, put yer foot doon, and a rear ward weight shift, should mek it also 50 / 50 !!!

think I need to go back, an dee a test with a driver , and the a driver an a passenger.
its easy  on my local, as there a bigg out side  LCD screen, so ye can see
just whats what is going on.

M

M

[BiTurbo228]

Quoted from david langrick

  My Car is a 1971 Spitfire Mk 4 with a 2,5 PI fitted moved back 6.5 inches
It has a Fibreglass Bonnet, front valances and bootlid.
It has a Saloon J type overdrive box , alloy engine back plate and Light steel flywheel -the new modern type.
It has minimal interior  with standard later seats, alloy  inner door panels . It has the Canleys alloy front hubs fitted.

car weight with soft top total was about  850 kg of which 460 was on the front wheels.
regards
Dave

Nice car that's close to what I'll have, except you've moved the engine back and I've near-bankrupted myself on lightweight alloy bits :S

What sort of work have you done on the engine, and what power do you think it's making? I was hoping for 170bhp, but I'm not sure what's optimistic with these cars.

Quoted from GT6 M

Heres a few weights which show the GT is not that far off ideal.
well im talking mine, maybe others are diff.

Nice car as well That's what I need to do with mine once it's done.

Is yours a GT6 rather than a Spitfire? It would be interesting to see what the difference in the weights of the bodies are as well.

[GT6 M]

Nice car as well That's what I need to do with mine once it's done.

Is yours a GT6 rather than a Spitfire? It would be interesting to see what the difference in the weights of the bodies are as well.


Diff is as stated, between  Daves Spitty 6, and a GT6
Butt, Daves Spitty will still be heavier than a Spitty due to engine / g. box he got in.
but a good idea between 2 like engined cars.

M

[david langrick]

Good evening
engine work is basic really ,  stock cross drilled crank  dynamically balanced with flywheel and clutch. TR5 new outright cam with new followers , flowed head, stainless valves with new standard guides. Standard 2.5 PI metering unit.
1-2-3 electronic distributor.

alloy water pump housing,  6-3-1 extractor manifold , inlets (early TR5 throttle bodies) opened out to match head , electric fan.
reliable , torquey , economical.  Not interested in BHP figure  but from the spec above you can work it out.
the car is fast enough with the weight reduction .

cheers
dave

[Martins Stag]

One thing that has been missed out that doesn't cost much is the driver!  Its one of the ways to loose weight with out spend money on bits!

On a serious note this is an excellent thread and realy usefull. I'll have to fine somewhere to get my car weighed to see what it works out at.

I wonder what is the minimum weight you can get a roadlegal Spitfire and GT6 down to?

Martin

[BiTurbo228]

Quoted from david langrick

Good evening
engine work is basic really ,  stock cross drilled crank  dynamically balanced with flywheel and clutch. TR5 new outright cam with new followers , flowed head, stainless valves with new standard guides. Standard 2.5 PI metering unit.
1-2-3 electronic distributor.

alloy water pump housing,  6-3-1 extractor manifold , inlets (early TR5 throttle bodies) opened out to match head , electric fan.
reliable , torquey , economical.  Not interested in BHP figure  but from the spec above you can work it out.
the car is fast enough with the weight reduction .

cheers
dave

That's pretty close to the spec mine will be at, except I got a bargain new TR6 150bhp cam rather than the slightly hotter TR5 one. Glad to hear it's a good setup

Quoted from Martins Spitfire

One thing that has been missed out that doesn't cost much is the driver!  Its one of the ways to loose weight with out spend money on bits!

On a serious note this is an excellent thread and realy usefull. I'll have to fine somewhere to get my car weighed to see what it works out at.

I wonder what is the minimum weight you can get a roadlegal Spitfire and GT6 down to?

Martin

Thanks

I know that the stock kerb weight for pretty much all cars includes a 65kg driver. Not sure how optimistic that is :S

I'm close to being able to figure out what it would be for a Spit6. All I need is weight stats for a stainless manifold and the alloy hubs and caliper brackets from Canley Classics. It's looking to be something close to 690kg minus whatever odd bits you can chop off.

Estimating from that it'd probably be something around 630kg

[GT6 M]

this mod saved about 1 1/3 lbs



M

[booley]

^^ what are they? are they the rear bumper brackets?

I've also seen door hinges drilled out with "speed holes"

[Richard B]

Taking the front bumper off, à la Pictons conversion would save some nose weight.


Re the drivers weight, think about moving the seat to get the best weight distribution. Of course you may need really long arms. 😀

[thescrapman]

Quoted from GT6 M

this mod saved about 1 1/3 lbs
M

I can park more than that on a good morning.

[booley]

Quoted from Richard B

Re the drivers weight, think about moving the seat to get the best weight distribution.

in Kas' book, he suggests deepening the driver's side floorpan to lower the car's center of gravity

[BiTurbo228]

Quoted from GT6 M

this mod saved about 1 1/3 lbs

M

Neat. I didn't realise that you could get that much weight off just by drilling holes. It might just be half a kilo, but if you do it to a host of things you could get a meaningful amount of weight off.

Also, a couple more weights:

Stock 2.5l sump - 3.539kg
GT6 sump + steel baffle - 3.68kg (forgot to weigh it before I welded the baffle in)

Stock transmission cover - 1.803kg

[BiTurbo228]

Another little bit of unintended weigh saving. Due to a stripped thread I got a new end cap, and it was alloy rather than steel.

Steel end cap - 0.238kg
Alloy end cap - 0.107kg

[esxefi]

that's the infamous 'bridge piece' which fits between the block/sump.

originals are alloy.it's the aftermarket ones which are steel,and for good reason,.....they tend to have stripped threads as you mention due to PO's over exuberance in tightening the bolts.
this is one component that I would sacrifice some weight for to be reliable in 'not leaking oil'

[BiTurbo228]

Quoted from esxefi

that's the infamous 'bridge piece' which fits between the block/sump.

originals are alloy.it's the aftermarket ones which are steel,and for good reason,.....they tend to have stripped threads as you mention due to PO's over exuberance in tightening the bolts.
this is one component that I would sacrifice some weight for to be reliable in 'not leaking oil'

Bugger, I've put it all back together again. Ah well i's got some sealing gunk in it so we'll see how it goes. If it's chucking out oil then I'll have to pull it apart again.

Oh, and I've thought of another place you can save a couple of grams. You don't need lifting eyes in day-to-day use, so they'll be coming off as soon as it goes in.

Lifting eyes (and bolts) - 0.223kg

[Richard B]

use a recoil kit to repair the stripped thread.

Surprised a steel one has failed, its normally the ali ones.

[BiTurbo228]

Quoted from Richard B

use a recoil kit to repair the stripped thread.

Surprised a steel one has failed, its normally the ali ones.

I was surprised as well. I thought I'd stripped the threads on the bolt originally, but no such luck there.

I looked up the price of a helicoil kit on eBay. It's a useful piece of kit to have, but it'll have to wait until next month. It'll be good practice though.

[BiTurbo228]

Couple of new weights I've found for the different types of crankshaft pulley: non-power steering ones and the ones with the extra pulley for the power steering pump.

OEM non-PS: 3.194kg
OEM PS: 3.832kg

Rimmerbros replacement non-PS: 3.703kg
Rimmerbros replacement PS: 4.341kg

The reason the Rimmerbros replacement ones are heavier like-for-like is that they have a thicker width damper, which should help with crankshaft vibrations.

[GT6 M]

Here a real weight saving one,  done that long ago, forgot it till I took,t box oot the other day

back plate drilled and cut oot where not needed
flywheel, drilled  aroound the outer rim,
and also  shaved a bit on inside

from memory, there aboot 12 1lbs come off




M

[bob dunn]

How was this done . And how was it balanced .I am fitting a 2000tc engine to my spit, the flywheel is 27.4lb (12.4kg) and this looks like a good plan.

[GT6 M]

Bob, done with a  { think it was } 18 mm drill, marked it all oot first, then just drilled away in the drill press.
Be  warned, ye may run into probs as it breks thru bak, as it comes thru on the slope,
which means it snaggs, so be v v care full, or yer drill,l brek.

back was turned doon in the lathe

I actually balanced it my self, by fitting a small bearing in the middle hole, then putting the thru bolt on to  2 side supports, thinking was, heavy bit would go to bottom, it did,
so just ground oot the holes at the bottom,
took aboot 4ish  hours all in, inc balancing.
just to be certain, bunged it on me Marras tyre balancer,  it was spot on.

back plate was done same way, just that on the bits that show to engine sides, it were no drilled right thru.  the inner bits, some were cut away altugitha, as they not really needed.
there quite a bit that can be took off the back plate this way

you will need a bigg drill press,  as ye will niva dee it with a hand drill
any use to ye,!!
M

[bob dunn]

Thanks M very good Cheers.

[BiTurbo228]

Quoted from GT6 M

Here a real weight saving one,  done that long ago, forgot it till I took,t box oot the other day

back plate drilled and cut oot where not needed
flywheel, drilled  aroound the outer rim,
and also  shaved a bit on inside

from memory, there aboot 12 1lbs come off

M

That's a hefty piece of weight saving there. I went with a lightweight steel flywheel from Chris Witor which saved 6kg (13.2lbs) over the heavy saloon flywheel I had, but that cost £350 and yours cost nothing but effort

Quoted from bob dunn

How was this done . And how was it balanced .I am fitting a 2000tc engine to my spit, the flywheel is 27.4lb (12.4kg) and this looks like a good plan.

I had a saloon flywheel on the 2500S/2.5PI hybrid engine I bought, and they're bloody heavy :S I wonder if they're heavier than the TR5/TR6 flywheels.

If you're going down the more money than sense route like me, I'd recommend Chris Witor's lightweight steel flywheels. They're £350 as opposed to the standard £500 from most other places, and they look magnificent

[BiTurbo228]

Got a new shiny thing from Canley Classics today alloy rotoflex wishbones

Cast iron: 2.258kg each
Alloy: 940 grams each

Not a bad little saving in unsprung weight