Heater re-circ mod

[Nefarious]

Can someone tell me exactly where the air intake is in the passenger footwell on cars with the heater re-circ mod is?

I always I assumed I didn't have the mod, as:
a) there's no visible inlet down there
b) the heater is rubbish

but I've just discovered that the passenger wing is all sealed-up inside (Early 1999 car).

I'm now wondering if the explanation for my rubbish heater is that it doesn't actually have an intake anywhere!

Edited by Nefarious on Wednesday 20th January 15:43

[VPower]

In the passenger footwell carpet, the bit that is up under the dash, there should be a black plastic vent.

This lets the air go under the dash and behind the carpets.
Behind this there should be a hole cut into the inner wing.

So air comes out the exisitng vents, through that plastic vent, through the hole in the inner wing and back out through the heater matix and the vents again.

[Gazzab]

It is a rubbish heater isnt it !! I never worked out why it didnt work. I had a quick look a couple of times but never found my way to the fan etc which I assumed must be full of crud.

[Nefarious]

I've got the black plastic vent (rotating type with two adjustable 'blades'), but can't see any holes anywhere.
V-Power: when you say "hole in the inner wing", I'm looking sort of where a tall passenger's toes would hit if they moved their left foot leftwards. Is that right? Is it literally a hole I'm looking for.

Gazza: The fan spools up enthusiastically enough. I think I might've cracked the problem here though!

[JensenA]

The vent is, or should be, in the carpet covered fibre glass panel that you pull out to to get to the ECU. It's just a round black plastic grill.

Gazzab - Access to the fan is in the passenger side wheel arch, there is a panel secured to the rear of the arch using the traditional TVR High tech patented method of large self tappers and a tube of silicone sealant.

[dean_ratpac]

I'm wondering if there's a way to improve the heating temp, and the force of the air coming through, the fan motor and wiring must be upgradable with an off the shelf part.

[Nefarious]

Sorry to be a pain, but could I trouble somebody with the mod to take a photo for me. I've apparently got no holes at all, and don't want to just start randomly drilling into the bulkhead!

[VPower]

OK Nef

You need to pull this bit out, see the vent in the top.



You will be confronted with a mess like this (I did pull the boxes off) but you can just see in the top left corner where the cheap carpet stuff I have pulled away.



Getting closer in there you should be able to see the two heater pipes that run into the matrix.



Now on my car it looks like the bulkhead in the corner under these pipes has been removed.
It looks like a shadow, but there are obvious marks where a bit of GRP has been removed.
It is not round, but rectangular-ish. I can actually get my hand into the gap.



I turned on the heater full blast and could feel the air being drawn up into that hole, but the best I do do was swipe one of SWIMBO's candles and make a bit of smoke to try and show the flow route.




Hope this helps??

Steve E Surrey TVRCC member. This Thursday meet lads!!

[Nefarious]

Very helpful - many thanks. I definitely don't have any of the interior mods.

Hmmm...seeing as I've got some ducting left over from my brake cooling pipes, I'm just wondering about taking a new pick-up from inside the engine bay to suck air from above the passenger side manifold...

[FarmyardPants]

Nefarious said:

Very helpful - many thanks. I definitely don't have any of the interior mods.

Hmmm...seeing as I've got some ducting left over from my brake cooling pipes, I'm just wondering about taking a new pick-up from inside the engine bay to suck air from above the passenger side manifold...

hot air with the added bonus that you'd know when the manifold develops a crack! Your next of kin would anyway.

[JensenA]

Nefarious - Thats exactly what I've been ivestigating. I did cut a hole in the engine side of the inner wing near the battery, but it is double skinned just there, and I didn't have the time (or the bottle) at that time to cut through to the other side, as I wasn't too sure what was on the other side of the inner skin. I reckon it should be simple enough though, a length of tubing bonded into the inner wing, and a 'Scooby' type bonnet scoop inside the engine compartment to force air in.

[Nefarious]

JensenA said:

I reckon it should be simple enough though, a length of tubing bonded into the inner wing, and a 'Scooby' type bonnet scoop inside the engine compartment to force air in.

TBH I don't think there's much need to force air in. That's kinda what the original re-circ mod was trying to avoid.

I was thinking about tapping into the inner wing around the level of the trailing edge of the F1 panel, to try to avoid the snakes' nest of wiring that's resulted from my nigh-on obsessive earthing.

Alternatively, rather than going in through the side, there is a bit of a gap to come in from underneath, and fit the tubing between the back of the F1 and the battery shroud bit of the scuttle panel.

ETA - where exactly does the fan housing sit longditudinally (say relative to exhaust ports 1,3,5 and 7)?

Edited by Nefarious on Tuesday 26th January 17:21

[VPower]

Just to say that heater mod (once warmed up) needs the cold fan on slow to stop you roasting!

[Gazzab]

I have a lateish Cerb. Even in current cold conditions I find I need both the hot and cold on at the same time to ensure I dont roast too much.
With the hot tured right down but still on and with the cold turned right down too , I then get the perfect heat level.

[JensenA]

Nefarious said:

JensenA said:

I reckon it should be simple enough though, a length of tubing bonded into the inner wing, and a 'Scooby' type bonnet scoop inside the engine compartment to force air in.

TBH I don't think there's much need to force air in. That's kinda what the original re-circ mod was trying to avoid.

I was thinking about tapping into the inner wing around the level of the trailing edge of the F1 panel, to try to avoid the snakes' nest of wiring that's resulted from my nigh-on obsessive earthing.

Alternatively, rather than going in through the side, there is a bit of a gap to come in from underneath, and fit the tubing between the back of the F1 and the battery shroud bit of the scuttle panel.

ETA - where exactly does the fan housing sit longditudinally (say relative to exhaust ports 1,3,5 and 7)?

Originally the air was forced in (at speed) through the hole under the indicator. I was thinking a bonnet scoop thing in the engine compartment would not have such a force pushing air in, but you could be right. The reason I don't like the heater mod is because the car mists up as it is re-cycling the cabin air.
The heater fan sits immediately behind the front n/s wheel arch.

Edited by Nefarious on Tuesday 26th January 17:21[/footnote]

[footnote]Edited by JensenA on Tuesday 26th January 23:04

[VPower]

Gazzab said:

I have a lateish Cerb. Even in current cold conditions I find I need both the hot and cold on at the same time to ensure I dont roast too much.
With the hot tured right down but still on and with the cold turned right down too , I then get the perfect heat level.

I was told all the later cerbs came with the mod straight out of the factory.
It became a TVR official mods, as one of the dealers did it first.
Does anyone know if this was true?

[Gazzab]

I believe it is true, it does encourage a bit of window steaming (my car hasn't been in the rain since I bought it).