Replacement V6 mondeo engine - mods

[zzr]

I've just picked up my new engine for my '95 mondeo and am busy cleaning all the inlet system up etc.

I have noticed that the lower plenum port sizes are much smaller than the port on the head.

Is it worth me getting the lower plenum ports bored out?
and larger butterflies fitted in the secondaries?
Is there anything that can be done to the top plenum to improve flow?

i don't want to spend too much time or money on the engine yet but just do some basic tidying up.

Also, can anybody recommend somebodywho can do the work?

Any advice welcomed.

Cheers,

Paul

[Boosted Ls1]

I work with the 24v cosworth engine quite a lot so may be able to offer some advice. It won't do you any harm to blend the tracts between the upper and lower sections if this will improve airflow, I'd go for it. Sounds like you are describing a nasty step.

Boosted.

[Mikey G]

IIRC the lowers on the later engines (electronic controled secondaries not vacuum) had bigger ports and butterflies.
Matching the ports will help although it is recommended you leave a slight step to help turbulence.

[zzr]

Thanks, mine is the early vacuum operated one, the step is about 3mm!! so I'll definitely blend them. I wonder if it is possible to modify the later larger ported one to take the vacuum system, that would save me some work.

Paul

[Zad]

The usual thing on these engines is to replace the Upper Inlet Manifold, Lower Inlet Manifold, and throttle body with items from the ST200 engine. The manifolds are extrusion honed to open them out and polish them, liberating a useful number of horses.

Mike