172 Conversion

[spryboy1974]

Has anyone looked into doing this and any ideas how much hassle the mounting will be?

The 172 seems to be hung from above but don't know if there is provision on the block and gearbox to utilise the R19 mounts??

Also will the exhaust/downpipe from the 172 fit the R19 ok??

Any help would be great as my valver is in need of some work, ie needs a clutch soon,seems to be down on power but this maybe a blocked cat,wheel bearing somewhere,rear discs.
My list of things to do is getting longer by the day!

 

[MicKPM]

The F4R will go in to a 19 on 19 mounts fine but you may have to use the 19's aux bracetry... i've not really looked at it in detail but i believe the F4R block is identical to the F7R block.



You will need to look for an early unit with a cable actuated throttle body or you'll have to swap the potentia-meter opperated unit later. You'll also need to run an aftermarket engine management that can run VVC (should you choose not to ditch it).

The exhaust will need some form of fabrication. I'd personally get something made to join the 2 systems at the Clio down pipe/19 mid section.

 

[Neal R19]

Yep all the 19's mounts will fit.

Might need a horrid bonnet bulge unless you use ITBs

A LOT of hassle when you can easily get comparable power from an F7R.

you won't be able to use the 172 manifold/downpipe as it would sit in the bulkhead. You could perhaps chop off the flange and bodge it to an F7R megane manifold. F7 exhaust ports/manifold runners are round, F4R ones are not though so it wouldn't be too great.

 

[spryboy1974]

Sounding encouraging so far.
What about gearbox mounting?

You mentioned something about a bonnet bulge - why?

Does the 172 motor sit at an angle?

Regarding the throttle,would it be posible to make the clio ,(fly by wire),pedal fit?

 

[Neal R19]

gearbox would mount exactly the same as the 19's JB3.

the plenum sits on top of the engine on the 172. greater overall height relative to the mounts. the standard F7P only just fits.

Trying to make the clio pedal fit is just making yourself more work. would be no use to you anyay unless you were to use the original 172 management. To do that you'd basically need the entire 172 wiring.

You'd have to check it out properly but last time I looked at a 172 up close, I could have sworn it looked like a Meg F7R throttle body would fit straight on the plenum...

 

[spryboy1974]

I would proberly remove the brace to give more height on top of the engine.

I have a stand alone management system kicking around so its looking like the only real problem will be the exhaust!?

Where there is a will there is a way!!!

 

[Gentle Ben]

Removing the brace wouldn't help... the inlet sits at the front on the F4R.