Inlet Valves

[Pysco]

The F7P has 30mm inlets, the F7R 32mm and the F4R 35mm if Im not mistaken. I know its possible to put 32mm valves into the F7P head as its the same head the F7R uses. BUT would it be possible to fit F4R inlet valves into the F7P/R head??? BenR, Slarty?

Cheers, Simon

 

[jimbo1]

the 32mm valves will defnatly fit, but im not sure about the 34mm valves. the stock valves are really close to the spark plug anyway, and an extra 2mm radius will be almost to the plug hole, then uv got the valve seat width as well. if u want a pisture of the 16v combustion chamber showing the valves, leave ur email and il send them to you.

jimbo

also, for the price of 8 32mm valves, the performance increase wud hardly be worth it i wudv thought.

 

[BUTRE]

where can I get the full spec on Renault engines? yeap.. Im asking a lot!

speaking of valves... What does the RT uses?

 

[N.D.Hill]

If you are thinking of putting the f4r inlet valves into the f7r/p type engine dont forget to change you valve guides as well. The f4r runs smaller stem valves.

 

[BenR]

Larger inlet will make a big diffeence if the ports can flow more than the inlets dictate can get past them. Total inlet area is the single largest determinig factor to the engines output.

But, i dnot ksow what the combined radii is of the 2 inlets and the inlet to exhaust.

just make sure the bridege between valves is no smaller than 2mm to be on the safe side, even this is pretty small.

32mm will make a diff, 35mm will make a huge diff, condsidering yuo match the port shapes and flow rates to the valves max flow potential