Just some questions
Just some questions
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ukbob

Original Poster:

16,277 posts

289 months

Thursday 4th November 2004
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After a spirited drive, if the temp is around 90, are there any benefits from cooling the car down before stopping and leaving the car for the night?

I assume the battory life is no different to a normal car, and that its fine to leave the cd player on when the car is off without having to worry about battory drain? Watching the volt meter dip violently when indicating made me wonder how much power the battory takes whilst driving, Ive read many threads about needing a trickle charger if you dont use your car regularly, but admit I dont know much about TVR electrics etc.

The guy who sold me the S did a few sprints in it with me, said if I drove the car like that all the time, the engine would be cooked within 3 months. How much is too much? How often does everyone here do 0-30 sprints? I like to take care of my S, or at least think I am

My car had an engine rebuild, and was run in properly after. What does this mean, exacly. What is involved in a rebuilt, does it make the car "better than before" (could it have anything to do with my 254bhp RR figures?) and this was likely a case of overthrashing the car, I assume. Is it 'bad' to have a car with an engine thats had a rebuild?

mgp1969

3,503 posts

261 months

Friday 5th November 2004
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don't know about the answers to your questions but don't worry about the voltmeter - 'cos mine doesn't work and not been able to source a new one!

Tripps

5,814 posts

296 months

Friday 5th November 2004
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ukbob said:
After a spirited drive, if the temp is around 90, are there any benefits from cooling the car down before stopping and leaving the car for the night?
You are supposed to leave them standing for a while to let everything cool down, especially the brakes as otherwise they mind bind when the handbrake is engaged - at track days you're always advised to park in gear to avoid this.

BUT my S never cooled down when standing as the fan simply wasn't powerful enough it much preferred to get some wind through the rad.

Probably why on track days you're advised to do a colling off lap...

ukbob said:
I assume the battory life is no different to a normal car, and that its fine to leave the cd player on when the car is off without having to worry about battory drain? Watching the volt meter dip violently when indicating made me wonder how much power the battory takes whilst driving, Ive read many threads about needing a trickle charger if you dont use your car regularly, but admit I dont know much about TVR electrics etc.
I wouldn't leave anything on if possible to sustain battery life.

It does of course depend upon how often you use it, when I got the S it would only last around seven days before a charge was needed but with since the new battery was fitted it'll do about 2 1/2 weeks. It did have an older alarm system in there that was never removed though which could not have helped mind you.

During indication the voltmeter looked as if it was doing the Samba much to the amusement of passengers, so I wouldn't worry too much about that.

KentishS2

15,169 posts

258 months

Friday 5th November 2004
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Rob,

When I have been for a spirited drive I always have a little sedate run through town before going home to cool off a little and when I get home I leave the car engine off but let the fan run to cool everything down. I'm going to also fit an override switch on my fan so that I can let it run for longer and also leave the ignition switched off as it doesn't do the coil a lot of good to leave the igntion on for too long.

Roy C

4,209 posts

308 months

Friday 5th November 2004
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IMHO opening the bonnet would probably be more effective than leaving the fan on.

bridgdav

4,805 posts

272 months

Friday 5th November 2004
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KentishS2 said:

when I get home I leave the car engine off but let the fan run to cool everything down..


Surely with the engine off and therefore water pump not circulating coolant, oil pump not circulating the hot oil - Leaving the fan on will only cool the water in the Rad...?

KentishS2

15,169 posts

258 months

Friday 5th November 2004
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Roy C said:
IMHO opening the bonnet would probably be more effective than leaving the fan on.


I didn't mention that but yes I do sometimes when it is still rather hot pop the bonnet so that the air can be blasted through by the fan, trouble is that hot air rises of course and there is only a small vent in the bonnet to let the hot air out!

GreenV8S

30,999 posts

308 months

Friday 5th November 2004
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KentishS2 said:

there is only a small vent in the bonnet to let the hot air out!


A problem easily fixed!

Notanutter

361 posts

259 months

Friday 5th November 2004
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ukbob said:
Ive read many threads about needing a trickle charger if you dont use your car regularly, but admit I dont know much about TVR electrics etc.





If like me you're only using the car at weekends, why not just disconnect one of the the battery terminals on a Sunday evening ? I've done that for years on my previous TVRs, it's also a pretty good anti-theft deterrant, or before I start doing that again is there something about V8S wiring that makes that not recommended ?

M@H

11,298 posts

296 months

Friday 5th November 2004
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bridgdav said:

KentishS2 said:

when I get home I leave the car engine off but let the fan run to cool everything down..



Surely with the engine off and therefore water pump not circulating coolant, oil pump not circulating the hot oil - Leaving the fan on will only cool the water in the Rad...?



Pretty much spot on.. Yep. Theres a bit of conduction of heat from the hoses into the rad too, but other than that the system is pretty static. You will have some air blast from the back of the fan onto the engine too I suppose, but thats not worth much.

Cheers,
Matt.

GreenV8S

30,999 posts

308 months

Friday 5th November 2004
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The battery lives in the boot, which is opened electrically ...

Notanutter

361 posts

259 months

Friday 5th November 2004
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Doohhhh....missed that one, thank God Homer's back on TV tonight !

ukbob

Original Poster:

16,277 posts

289 months

Friday 5th November 2004
quotequote all
GreenV8S said:

KentishS2 said:

there is only a small vent in the bonnet to let the hot air out!



A problem easily fixed!


Notanutter, the battory is in the boot so disconnecting it isn't possible ... unless there is another location to disconnect, but I use my car daily anyway so probably dont need to.

Cheers for all the helpful posts Any ideas about the rebuild guys?

KentishS2

15,169 posts

258 months

Friday 5th November 2004
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M@H said:

bridgdav said:


KentishS2 said:

when I get home I leave the car engine off but let the fan run to cool everything down..




Surely with the engine off and therefore water pump not circulating coolant, oil pump not circulating the hot oil - Leaving the fan on will only cool the water in the Rad...?




Pretty much spot on.. Yep. Theres a bit of conduction of heat from the hoses into the rad too, but other than that the system is pretty static. You will have some air blast from the back of the fan onto the engine too I suppose, but thats not worth much.

Cheers,
Matt.


I'd agree with that genearally but I think it is better to let it cool a little rather than just switch off with the fan running and parked inside the garage.

So from what you have said you would leave yours to tickover to circulate the water in the engine whilst the fan is on. Surely it will just get hotter if you do this and the fan will keep cutting in?

Tripps

5,814 posts

296 months

Friday 5th November 2004
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GreenV8S said:
The battery lives in the boot, which is opened electrically ...
I guess you could leave the boot opened in the garage if its dry enough and not too dusty...

But then it won't be much use to stop a scrote having it off.

M@H

11,298 posts

296 months

Friday 5th November 2004
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KentishS2 said:


So from what you have said you would leave yours to tickover to circulate the water in the engine whilst the fan is on. Surely it will just get hotter if you do this and the fan will keep cutting in?




The thing is if you've been caning/hooning your car, you have a big thermal gradient between the engine and the radiator.. the engine water is at say 150+ degrees and the rad water is at 75 degrees with the fan on.. if you just stop the car and turn off the engine all the heat in the block is still there and in some cases (my old chim did this once at a trackday) you can switch off, then 10 seconds later the pressure cap starts steaming as the block continues to heat the water.

If you cruise the car for a bit first and then leave it ticking over with the fan on until the fan stops, then switch off the engine, you are dramatically reducing this themal gradient and removing the excess heat from the engine block

Cheers,
Matt.


>> Edited by M@H on Friday 5th November 10:06

KentishS2

15,169 posts

258 months

Friday 5th November 2004
quotequote all
When I've had a bit of a blast I will have a sedate drive for 10 mins before parking on the drive and I wait for the fan to switch off before turning off but as she is standing if I leave the ignition on the fan may cut in again, if it does I leave the ignition on until it switches off again, just too cool things down a little further.

I guess the best thing to have is a secondary electric water pump which cuts in when the fan is running to aid cooling and also circulate the water more rapidly.

If you made this circuit live with the ignition off you'd still be circulating the water and cooling it simultaneously.

keithyboy

1,940 posts

294 months

Friday 5th November 2004
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ukbob said:
. . .
My car had an engine rebuild, and was run in properly after. What does this mean, exacly. What is involved in a rebuilt, does it make the car "better than before" (could it have anything to do with my 254bhp RR figures?) and this was likely a case of overthrashing the car, I assume. Is it 'bad' to have a car with an engine thats had a rebuild?


Bob, it really does depend on what exactly was replaced, what parts were used and who put it all back together. A rebuild can involve replacement of all internal engine parts or only those that are damaged/worn and can be with either OE parts, pattern items and/or upgraded ones. It also depends on the diligence of the guy putting it all back together - e.g. proper torque settings, matching parts properly, shimmimg etc. etc. Without more info its a difficult one to answer - although given your bhp figures its unlikely its rebuilt to standard spec.

UKbob

Original Poster:

16,277 posts

289 months

Friday 5th November 2004
quotequote all
Ive got a manual fan override switch, and use it to cool the car down before coming home sometimes. When I pull up, ignition off, the sump(?) makes a sound which equates to the rumbling stomach of a giant (water gurgle suckle bubble groan)

GreenV8S

30,999 posts

308 months

Friday 5th November 2004
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The secondary electric water pump idea works very well to disperse heat soak, but you need to be very careful how you fit it or it can restrict water flow at high revs. However, whatever you do to the cooling system, it is a very bad idea to come screeching to a stop after a thrash and switch off straight away. The whole car will benefit from a couple of minutes (at least) gentle driving to let the engine, transmission and brakes cool off.