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mg_tf
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Thanks for all the replies! This must be the fastest response I've ever had on a forum.

The replies have put me much more at ease and its good to know that the car is happy to run at high revs. I am really enjoying my little TF and plan to keep it for as long as possible so, just like many new buyers of TF's that I have seen on here, I am wary bordering on paranoid about engine failure and overheating.

I dont want to turn this into another HGF post but wouldnt the engine generate much more heat at higher speeds? Is there a big difference between heat at 3400rpm at 70mph compared to 2600rpm at 55mph? I know everyone says to give the car a good blast but I cant help but feel like I'm tempting fate by running it hard.

Just for a hypothetical question to clarify what people are saying and not suggesting driving in this way but, would driving the TF at 3800rpm at 75-80mph for extended periods of time without stopping (3-4 hours) cause any added risk to the engine? (Sorry if thats a N00b question).

I think cjmillsnun raises a good point about engine noise due to the location of the engine and thats probably something a new driver of a F/TF needs to get used to.
 

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In the Garage
MG TF
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I dont want to turn this into another HGF post but wouldnt the engine generate much more heat at higher speeds? Is there a big difference between heat at 3400rpm at 70mph compared to 2600rpm at 55mph? I know everyone says to give the car a good blast but I cant help but feel like I'm tempting fate by running it hard.

Just for a hypothetical question to clarify what people are saying and not suggesting driving in this way but, would driving the TF at 3800rpm at 75-80mph for extended periods of time without stopping (3-4 hours) cause any added risk to the engine? (Sorry if thats a N00b question).
The engine may run slightly hotter but it's been designed and tested in much hotter tempretures then we ever get in this country for longer periods of time that we are likely to drive in.

Development engines will have been run for weeks at a time at max RPM.
 

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Thanks for all the replies! This must be the fastest response I've ever had on a forum.

The replies have put me much more at ease and its good to know that the car is happy to run at high revs. I am really enjoying my little TF and plan to keep it for as long as possible so, just like many new buyers of TF's that I have seen on here, I am wary bordering on paranoid about engine failure and overheating.

I dont want to turn this into another HGF post but wouldnt the engine generate much more heat at higher speeds? Is there a big difference between heat at 3400rpm at 70mph compared to 2600rpm at 55mph? I know everyone says to give the car a good blast but I cant help but feel like I'm tempting fate by running it hard.

Just for a hypothetical question to clarify what people are saying and not suggesting driving in this way but, would driving the TF at 3800rpm at 75-80mph for extended periods of time without stopping (3-4 hours) cause any added risk to the engine? (Sorry if thats a N00b question).

I think cjmillsnun raises a good point about engine noise due to the location of the engine and thats probably something a new driver of a F/TF needs to get used to.
Obviously it will generate more heat at higher speeds, but the cooling system is designed to deal with it. The F and TF have a radiator with an electric cooling fan at the front, and in addition to keep the engine bay temperature down, a fan that draws in cold air from the right hand side vent behind the door that cuts in where necessary.

The best prevention for HGF is :

1. Check the coolant level as often as possible. I tend to do it every time I open the boot and at least once a week (do not unscrew the header tank cap when the engine is warm though!). Any coolant loss needs investigation.

2. To let the car warm up (not just the water temperature but let the oil warm up) before taking it past 3k rpm. Once the oil
temperature gauge has started to move, you can freely give it some.

3. Service the car according to the schedule and change the water pump (and cambelt tensioner) when changing the cambelt.

4. When the coolant system is drained and refilled after maintenance then bleed the system (instructions are in a how to on here - if you're not doing the work, give them to a garage - or even better use one of the mobile mechanics on here. They're known and trusted within the community and know these cars intimately). There are 3 bleed points and it is important that any air is bled from the system.

5. Apart form the 4 conditions above. Don't panic and enjoy the car. If the gasket has been changed and done properly (or if you're still on your original gasket), it is probably unlikely to go unless you don't deal with coolant loss.
 

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The power is there and you shouldn't be afraid to use it. I've had my car to 7300 RPM (it's a VVC so it can rev higher) and it was fine.[/QUOTE]

I do this too......Regularly :eek:
Well, it is a sports car![/B]
 

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The power is there and you shouldn't be afraid to use it. I've had my car to 7300 RPM (it's a VVC so it can rev higher) and it was fine.
I do this too......Regularly :eek:
Well, it is a sports car![/B][/QUOTE]

I do too. Considering a remap to allow higher revs.
 

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At a steady 70mph the car requires around 15-20bhp, which means given that the overall energy conversion efficiency of the engine is low because you have a big pumping loop loss due to the relatively low throttle angle the cooling system is absorbing and rejecting around 15-20bhp-worth of power.

Even in Doha on a warm day that will cool easily with a 70mph draught over the radiator.
 

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mgf
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something happens when you go faster.... :)

the airflow thru the rad is faster, its faster all around the car, it removes heat faster, because everything that gets hot radiates heat... so the air thats flowing around the hot bits absorbs the heat, and because its moving fast, it carries the heat away..

?

so the faster you go.. the more airflow there is, the faster the hot air is taken away and replaced with cool air... so.. the faster you go the better the system is at keeping the temperature below alarm levels..

alarms really occur when the airflow isnt sufficient to take away the heat the engine generates... like in traffic, moving slowly on a hot road on a hot day..


the F will drive happily at its max speed.. for hours... ive done it.. i have no problem in taking the Freestyle or my Trophy up to 120 plus MPH ... the Trophy has sat at 130 MPH for an hour or more behind a Porsche Carrera... its in its element..

but get either sat in slow moving traffic on a hot day, hot road, and the fans come on.. the cars are not happy.. stifled, suffering being stuck and too hot..

no airflow... coolant not going around fast enough... nothing to take that heat away..

the car performs better on an open road... speed is not its problem...
 

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If your like me and have been driving diseasels for the last 15 years then it is hard to get used to the higher revving of a petrol car. Add to that it is lower geared because it is a sports car you will feel uncomfortable sitting at motorway speeds for any length of time.
I don't think these cars are designed to be motorway cruisers, if they were they wouldn't be so much fun.
 

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mgf
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motorway cruisin isnt fun?
ok i accept the opinion but i cant agree with it.. i have two mg`s that tell me they love motorways..
 

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Motorways are fine (though mine doesn't feel rock solid at high speeds...polybush time soon I think)


As I understand it:
What you don't want to do is go at 100MPH for an hour on a hot day and then get stuck in a long queue of traffic...this is the most common situation in which HGF occurs without any coolant leak.

The reason being is that the engine will be properly up to temp and you will sit in traffic and suddenly the thermostat will open and flood the engine with very cool water. The sudden shock of the temp change can cause the gasket to go.

The car is meant to be driven, make sure you keep a few hundred notes to one side in case of emergency and then just don't worry... if it goes wrong it goes wrong but worrying won't change anything.
 

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If your like me and have been driving diseasels for the last 15 years then it is hard to get used to the higher revving of a petrol car. Add to that it is lower geared because it is a sports car you will feel uncomfortable sitting at motorway speeds for any length of time.
I don't think these cars are designed to be motorway cruisers, if they were they wouldn't be so much fun.
I've been driving a diesel 4x4 for over 20 years and I dont have a problem with revs in the MG. Give it some.
 

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K series

Its worse for a K series engine to plod at low revs in a high gear than it is to rev it.. On motorways my 1600 K series used to get driven at a good pace On our regular runs to Cornwall we used to leave home at 10:30 pm when the m25 was nice and clear and be at our seasonal caravan in 3.5 hours without stopping, 4 hrs with a comfort break :) As everyone has quoted as long as your engine gets its services and weekly checks it will be fine lots of noise could be lessened by adding extra soundproofing Sure there's a few how to's on doing that
 

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It always amazes me how people are frightened to take the car up to the red line. Most cars will happily sit all day just below it. It is beneficial to run a car hard occasionally and is known as an Italian tune up. It clears the crud from the engine.

The K series in particular loves being revved hard. I can understand a new owner may be unsure because the car will be very noisy. But this is because the engine is right behind your head.

The power is there and you shouldn't be afraid to use it. I've had my car to 7300 RPM (it's a VVC so it can rev higher) and it was fine.
 
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