MFI fuel mixture thermostat re-design

[AndrewWolfeUK]

Hi Guys,

As most of you know the thermostat operates by the heat from the exhaust through a heat shield. Its symbol shims expand and push a shaft, which pushes a rocker/lever, which in tern controls the mixture.
Well my heat shield has a fairly large hole and is well rusted through, its to rusty to repair. The exhaust under it, is however in good condition. I'm not going to buy a new exhaust. Some of you will think my idea is gash, other may think its pure genius.

I plan to remove the thermostat and replace with a blanking plate, with a long bolt running through a tapped hole in the middle of the plate. I will measure how far in it needs to go to lean the mixture fully and tack a nut to the bolt in this position, to make the adjustments more accurate and so not to screw the bolt in to far.
Seeing as its going to be a manual adjustment i thought id tack a key handle type thing to the bolt head, so it can be adjusted without the need of tools.
Take a look at the picture and let me know what you think...

Cheers Andy


I just had an after though, I may put another nut on the bolt so it can be locked once adjusted.

[Scott Clarke]

Andy-
Supertec makes a device similar to your idea, except that it is connected to a cable, allowing the adjustments to be made from the cockpit. How would you adjust yours as your car warmed up?

[mhackney]

Scott, I scourted the Supertec site and could not find this device. Have you seen it there and if so could you post a link please?

cheers,
Michael

[HawgRyder]

I use one of these right now.
Works when warm OK.
When first starting...I have to use the enrichening circuit a bunch to get the engine to run evenly.
In colder weather...it takes forever to warm up to the point that I no longer need to play with the enrichening knob.
And....I get lots of reluctant noises from the engine (missing and kicking) while it warms up.
That said...it has fixed my running warm problems...and allowed me to tune the beast for high RPM when hot.
I am going to change this fixture to a cable or electric solenoid type soon so that I will have control for cold starts.
Bob

[AndrewWolfeUK]

Oooh, a cable operated version...

I will do some research into the supertec version, if i cant source one, i'll make one.

Thanks for that guys, just goes to show what discussing an idea can lead to. With a cable operated version, I may never need to open the decklid ever again! LOL

[AndrewWolfeUK]

just found this pic under the bosch section on the supertec website, a manual version....

[AndrewWolfeUK]

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