Got my 172 Inlet Manifold

[Simon]

Its out of a damaged car that had fire damage.

It all looks OK, casing is all sooty @ the moment should clean off.

Does anyone know what sort of temperature would be required to damage the manifold. I think it is made from Alluminium. Dont want to do work on it to find out that it is too brittle and would break up whilst in use.

 

[Simon]

Manifold is OK however:

It would appear that Renault have done a first class flow job with the manifold as standard !

Normally to make an improvement the throttle body butterfly is enlarged along with the entry to the plenum chamber where the body bolts on. Thus more air going into the inlet manifold although flow may slow down and thus torque will suffer at lower RPM and BHP increased @ higher RPM.

With the 172 plenum chamber there isnt enough metal to drill out to get any big gain and the same applies to the throttle body.

Sticking on a larger throttle body without matching it to the plenum chamber will give gains however air will get obstructed on entry to the inlet manifold thus reducing the benefit.

Also within the butterfly Renault have made a purposeful lip which stops air going over the top of it and only allows air underneath at certain slightly open positions. This apparently is designed to give smooth pickup.

Apparently on VW golfs there is loads of metal that can be cut out and thus this is an area where good improvement can be had.



There is a solution to increasing the size of the entry to the plenum chamber but this involves welding new bits in place where metal has broken away because of the drilling.

Ive been advised that it really isnt worth doing these mods. to a road going 172 because drivability will take a hit and obviously the cost of doing it.

I probably would have risked it if there had been plenty of metal to cut into and I could use existing parts.

Bummer