Single throttle body + plenum upside down

[Davemk1trackcar]

Hi All

Have a Caterham TB + Plenum (off a 2L Duratec car) which I hope to fit to my Mk1 (with Duratec).

To avoid modifying the firewall/bulkhead I was planning on fitting the TB + Plenum upside down, with an adaptor plate to allow fixing to the cylinder head. It would then face towards the front rather than the rear.

Any potential problems with this approach? Just trying to save cost, much cheaper than ITBs.

[katana]

Assuming the head has cast in injector ports then no, fitting upside down will cause no issues other than the plenum drain will no longer drain ! I'm surprised it fits at all - its a chunky sucker! Remember to turn the TB up the right way!

[Davemk1trackcar]

Thanks, turning the TB the right way up wont be easy as the bolts wont line up with the plenum, its not symmetrical. Does it matter if the TB is upside down, it's cable operated with a spring so the throttle should open the same?

[Graham]

throttle body wont care which way its up

[SimonD]

Once the plenum is flipped the throttle body will end up quite low down because of the angle designed into it, if you can make it work it's a great plenum

I know the early alloy version has been chopped before

[katana]

throttle body wont care which way its up

I know it won't - I was thinking more of logistics for cable pulls and accessibility ! To the OP - sorry for comment as it looked symmetrical to me!

[alladdin]

given that all other costs of the conversion are the same inc ECU , how much will you be saving ? it doesnt look like a cheap part to purchase ?

[Davemk1trackcar]

it was less than £300, a fair number of Caterham owners have changed to TBs (at a cost of c. £5k for an additional 10hp!) so have them spare and not much of a market for them.

TBs seem to be minimum £1k so a fair saving, unless others know of cheaper TBs?

[alladdin]

i will pm you