Heat…

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r500_wkd

Original Poster:

18 posts

100 months

Saturday
quotequote all
Picked the car up this afternoon and drove it 250 miles home. What a fantastic bit of kit. It’s a T350c with a Powers 4.3 and a 3.9 final drive. I bet it’s nearly as quick as my old R500.

Anyway, all good apart from the heat. The whole centre tunnel seems to radiate heat, even the alloy gear knob gets hot. Not helped by the fact that as soon as I got into traffic I got “aircon fail” come up on the warning panel. Seemed to work reasonably when motoring along.

Is all that heat from the engine or is it the cats? Has anyone successfully managed to reduce it significantly?


Adrian@

4,350 posts

285 months

Saturday
quotequote all
TVR Powers do a Titanium replacement of the OE TVR F0889 (theirs is TVR F0889T). A@

Granturadriver

597 posts

264 months

This "Air con" fault message is not uncommon if the air conditioning system is used for a longer period of time. It does not actually mean anything.

Because of the heat in the car, on the center tunnel and the gear lever: check the ventilation setting. If this is set to cold, no air should be blown out of the hot air nozzles. If this is the case, you will need to set the heating flap differently via the menu. If the setting is correct, this has an effect on the overall heat balance.

As far as the gearshift is concerned, there are two variants. There is now an encapsulated gear knob and there is the titanium gear lever, which also does not conduct heat. However, installing this lever is more complex. I can live without these modifications.

non_linear

289 posts

86 months

Check Graham Varley's comments on how to check the aircon is set up correctly.

https://www.pistonheads.com/gassing/topic.asp?h=0&...

BritishTvr450

70 posts

2 months

As the cars age and the transmission tunnel sound proofing breaks down or simply falls away from the body as it’s basically glued on this can increase gear knob heat and transmission tunnel heat soak.

In truth they have always heated up since new.

I’m not sure if the later cars produce more heat in this area but new sound proofing material and very regular gearbox oil changes reduced my gear lever heat considerably on my Chim unless stuck in slow moving traffic.
As soon as I'm upto speed it comes back down to a more acceptable warmth rather than very hot.
For me replacing the oil regularly made the biggest difference to both the heat and slickness of gear changes.

Adrian@

4,350 posts

285 months

Encapsulated gear knob...is there a link? I have just had a my gearbox rebuilt (properly this time, as it had been rebuilt incorrectly) and have looked at the Titanium one from Dom, (I have a new alloy one as the original one had the threads failed a year or so back) and have baulked at the price ATM. A@

r500_wkd

Original Poster:

18 posts

100 months

Thank you all for your help.

Just been reading the advice from Graham Varley - looks like I've got some investigating to do to see what set up I have and them possible some adjustments to make.

Sounds like I could improve the heat from the tunnel by replacing/improving the insulation another job for the list. If anyone has a link to any specific material that has worked really well I would be very grateful.

This ceramic heat break for the gear stick sounds a very interesting solution - anyone got any links to where I can find one - tried google but not having much luck.

mk1fan

10,582 posts

228 months

Powers sell the titanium gear lever - it is the shaft you refit the knob. They also sell an alternative knob which I like.

I have a set of Clive F 200 cell sport cats (original ones have started to breakdown) which are smaller and replacement manifolds ceramic coated ready to be fitted once I can source some 12mm four-wire o2 sensors. At the same time I am going to add exhaust wrap to the front of the exhaust pipes up to the cherry bombs.

r500_wkd

Original Poster:

18 posts

100 months

mk1fan said:
Powers sell the titanium gear lever - it is the shaft you refit the knob. They also sell an alternative knob which I like.

I have a set of Clive F 200 cell sport cats (original ones have started to breakdown) which are smaller and replacement manifolds ceramic coated ready to be fitted once I can source some 12mm four-wire o2 sensors. At the same time I am going to add exhaust wrap to the front of the exhaust pipes up to the cherry bombs.
Just googled CliveF - he's on the South Island, not far away at all. Might talk to him about the problem and see what he suggests. If I can make it cooler below and add insulation to the tunnel I'm hitting it from both sides.

r500_wkd

Original Poster:

18 posts

100 months

What's the legality of decat on these cars?

I know after 1992 any car fitted with a cat has to keep it, but it looks like TVR slipped through the small manufacturers loophole and didn't get emissions tested so at MOT there's no standard for them to meet. Seems to be a bit of a grey area.

What have others found? If I could take the cats out of the system and wrap the exhaust tubing I would save a whole lot of heat build up in the tunnel.

sixor8

6,375 posts

271 months

It's more to do with having a 'friendly' MoT tester than anything else mostly. wink

Legally, cars manufactured in 1992 but not registered until early 1993 are considered under the previous emissions, the last Ford Sierra cars for example.

non_linear

289 posts

86 months

For some reason I've never had a heat problem with my T350, maybe a previous owner sorted it, and I still have cats fitted.

If I did have a "hot knob" problem I would think about drilling the thread out on my gearknob and then bonding a ceramic nut in.
Build a thermal barrier into the gearknob.

https://highperformancepolymer.co.uk/products/cera...


Edited by non_linear on Sunday 30th June 13:58

mk1fan

10,582 posts

228 months

If you are wanting to go the deCAT route. I have a set of never fitted Clive F deCAT pipes, ceramic coated in matt black.

I am not going to use them. Send me a PM through my profile if you're interested.

TVR Tommy

615 posts

228 months

Go decat, it reduces heat soak into the cabin massively. I did 2 years with the cats in and had the hot gearstick and uncomfortable atmosphere on a hot day. I have a T but no aircon.

Just a bit of a pain come MOT time as it’s a faff swapping them out.

Modrich

180 posts

23 months

1st question, what is involved in fitting the Titanium gear lever as I can't see how to remove it with the gearbox insitu.

2nd question, why use Titanium when stainless steel is cheaper and has 30% greater thermal resistance?

Adrian@

4,350 posts

285 months

Modrich said:
1st question, what is involved in fitting the Titanium gear lever as I can't see how to remove it with the gearbox insitu.

2nd question, why use Titanium when stainless steel is cheaper and has 30% greater thermal resistance?
The gear lever extension (F0890/T) fits with a Allen bolt through a rubber bush and holder which fits to the gear lever extension of the gearbox with a grub screw. (Once you have the knob, centre console them rubber boot removed you remove the grub screw and the whole assembly lifts away for you to access the Allen head through the holder).
I cannot say I know the thermal property of the materials, but that the lever is remoted away from the gearbox by the rubber bush there is little if any heat that can be transferred from the gearbox itself. A@

Note that it has taken me numerous attempts to lock the grub to the gearbox extension (I did it in the end by tungsten grinding an indent in the gearbox extension with a long nosed grinder and ball tungsten) as this whole assembly also has the reverse gear switch selection arm AND that is a pain to get 100% right if the grub will not lock into postion.

Edited by Adrian@ on Monday 1st July 07:52

Modrich

180 posts

23 months

Adrian, thanks very much for your explanation.

So if the hot gear knob is caused by heat conducted from the gear lever 'extension', but the source of that heat is NOT through the rubber 'isolator' bush below it, then the heat source can only be hot air from the exhaust/cats below. Convection not conduction.

If this is the case, then I may have helped with this issue by binning the Ford transit rubber boot and replacing with an up-side-down Mazda Miata boot that fits snugly to the rubber isolator bush, therefore stopping any hot air getting past and heating up the gearlever, see below:





I haven't tested it yet or driven the Tuscan but it's not far off...

Edited by Modrich on Monday 1st July 21:35

Granturadriver

597 posts

264 months

Yesterday (07:15)
quotequote all
Two thoughts on removing the cats: the car gets significantly louder and sounds more tinny, and it stinks.

I was glad when I had the cats back in after several weeks.