Sagaris bonnet flaps/vents - anyone motorised ?

[tvrloon]

Hi,

I am looking at motorising the bonnet vents/flaps on the Sag and was sure someone on here had done it already but I can't find the info.

So, has anyone done this and could save me re-inventing the wheel ?

I know TVR didn't bother as it kept cooking the motor which, for some reason, they put in the hottest place in the engine bay. I'm sure it's possible by moving the motor elsewhere.
Just considering the various options at the moment.

Any info/suggestions very much appreciated.

[blackiepaul]

some chap with a lime green Sag has done it (there are two lime green sags). I would not do it myself, I think the idea is great and I can see why you would like to do it but the service bonnet is so heavy as it is and I would want to be reducing weight not adding to it.

[tvrloon]

Thanks Paul.

I was thinking of mounting the motor elsewhere and not on the service bonnet and using some kind of linkage to the flaps.

I'll see if I can track down who did it.

[The real Apache]

Pneumatics would be an advisable solution. Nick the vac tank and fittings off an old saab 900s ventilation system and I'm sure you could knock something together that would weigh next to nowt

[VARLEYHYD]

Work in progress for me, just too busy.

Not decided on connection method, mechanical or electrical yet.
Had considred making the linkage go overcentre if a rotary motor used.

Try this link for a linear actuator
LAM3




G

Edited by VARLEYHYD on Tuesday 31st August 15:50

[blackiepaul]

Done some digging - here is a pic of it, looks like the same kit that G is talking about?

[tvrloon]

Strangely enough it was the LAM3 actuator I was looking at.

Only problem is it's rated at upto 60C, it's got to get hotter than that mounted above the manifold hasn't it ?

Did think of indvidual motors (small) on each flap with worm drive.

Also got to ensure the bonnet can be opened if the motor fails.

Lots to think about and experiment with.

Wasn't at all sure of the kind of pressures that would be on the flaps.

[Don1]

Hmmmm... liking the one-piece bonnet, but not the wing mirrors....

[tvrloon]

I've just undone the existing retaing bolt on the lower flap to see what it looks like when closed.

The seperator between the top/bottom flaps is arched, unfortunately the lower flap isn't (or is but not as much) and you get a step between the flap and the service bonnet at the top and it looks rubbish !

Looked at the LAM3 actuator, struggling to find a uk supplier. Current price is £191 + delivery.

Looking for cheaper alternative or way of doing it.

[The real Apache]

tvrloon said:

I've just undone the existing retaing bolt on the lower flap to see what it looks like when closed.

The seperator between the top/bottom flaps is arched, unfortunately the lower flap isn't (or is but not as much) and you get a step between the flap and the service bonnet at the top and it looks rubbish !

Looked at the LAM3 actuator, struggling to find a uk supplier. Current price is £191 + delivery.

Looking for cheaper alternative or way of doing it.

Try air

[tvrloon]

The real Apache said:

Try air

I've never used pneumatics at all so wouldn't have a clue what I'm looking for or what I'd need.
Any pointers ? I didn't get far with finding info on your Saab suggestion above.

Edited by tvrloon on Friday 3rd September 12:58

[The real Apache]

tvrloon said:

The real Apache said:

Try air

I've never used pneumatics at all so wouldn't have a clue what I'm looking for or what I'd need.
Any pointers ? I didn't get far with finding info on your Saab suggestion above.

Edited by tvrloon on Friday 3rd September 12:58

Find an old 900, behind the r/h wheel arch front will be a plastic bottle resembling a washer bottle, grab that and the pipework and what valves it connects to on the heater and vents, this'll be the bones of it. You'll have to figure out how to adapt it to move the flaps. You might need to buy some bigger pistons from Festo http://www.kiowa.co.uk/Festo_Pneumatics?gclid=CNfG... or someone like that. The biggest issue will be where to pick off the vacuum on the manifold but just copy from the donor.

[paul1962]

There are some very lightweight 12v actuators around which I've used on other projects.
Might be ok for this job, I've not worked out exactly what spec is required here.
The flaps are quite light but what sort of pressure is on them when the car is moving, especially at speed ?
Temperature is another problem, many actuators max out at somehwere between 50 and 65C, I assume it's going to get hotter than that under there ?

Define the spec and work from there.

[blueg33]

My thought would be to use some servos as used on rc sailing boats, but hardwire them in. The winch servos would probably be heavy duty enough, but they are not very heavy in themselves

[i remember]

blackiepaul said:

Done some digging - here is a pic of it, looks like the same kit that G is talking about?

Thats looks awesome, seriously seriously awesome

[paul1962]

VARLEYHYD said:

Had considred making the linkage go overcentre if a rotary motor used.
G

Hi Graham,

Not sure I understand what you mean. Can you explain ?

This mechanical stuff is far too complicated, give me electronics any day of the week.

Paul

[paul1962]

blueg33 said:

My thought would be to use some servos as used on rc sailing boats

Been a long time since I played with rc servos, they don't have any holding torque when unpowered which might be a problem.
The flaps are approx 1kg so plenty of servos can easily exceed that, could be problems with any additional force when the car is being driven ?
Nice idea, especialy as they're easy to control.
Not sure they'd survive the environment.

I like the linear actuator approach.

[R400TVR]

I know this is an old, old topic to reply to and drag up but I came across this on YouTube and had to post it uphttps://www.youtube.com/watch?v=BxHx1vuxzXc
and
https://www.youtube.com/watch?v=0BtaZ0gGjes

[paul1962]

This thread is nearly 4 years old!

The car in the video belongs to alex_gray255.

I've basically the same system on mine but with newer control ecu which I believe Alex is having fitted soon.

I don't know how many cars have had this done. I'm sure Alex will know.

[alex_gray255]

Mine
Paul's
John's
One in Netherlands

Mine and Paul's run off an ECU/manual override system. The
ECU programs are slightly different as we have both tailored
them to different criteria. Mine is also being revised
for the new bonnet design.

John's uses cooling fans to trigger

One in Netherlands runs a system similar to John

Edited by alex_gray255 on Saturday 17th May 01:03