throttle bodies

[thud]

has anyone tried a larger throttle body on a 133. if so are their gains to be had.

 

[oscar]

no gains to be had whatsoever, and anyone who tells you otherwise is a complete fool. a naturally aspirtated engine can only pump as much air as the stroke of the engine will allow and the current throttle body is already more than adequate to allow an ample amount of airflow through it would be a complete waste of money

 

[Dubz]

I believe the throttlebody on the 133 is the same as the Clio 197's so it's perfectly capable as Oscar said

 

[singlespeed]

As above, its the same 60mm body as the clios and its very marginal whether they get any gain/loss by getting theirs bored out to 63 or 64mm. Some have gained a bit and actually had an improvement, whilst others have gained a bit top end but ended up with rubbish idle /low speed pickup... Depends on who's mapping it as well, but pointless for us.

There's a small step either side of the butterfly which you can smooth out fairly easily, so the 60mm machined bore blends into the rest of the casting slightly better. Blutac or plasticine, lightly pressed round the edge of the butterfly and ends of the spindle, to protect the edges and spindle bearing from dust and filings, then use a fine sanding drum on a dremel. Don't force the butterfly round to the open position as there's a slight risk of damaging the stepper drive motor.

 

[thud]

Cheers guys, I guess any restriction is on the exhaust side, what goes in has got to come out !!

 

[oscar]

better breathing is always good you could look into an exhaust and throttle bodies, although this would run you into the best part of a grand and a half! neils car is currently sitting at around 160bhp with throttle bodies and cams + standalone engine management

it's aweeeeeesome

 

[singlespeed]

You could look at cleaning up the inlet manifolds and better matching them to each other and the cylinder head ports. Mine needed a fair amount of fettling at the port connections.