Clio Williams F7R vs. Megane Coupe F7R

Site Subscriber Joined: 07 Oct 2004 Posts: 2281

I know there's a lot of relevant information scattered throught many threads on Retro but as you all know I've got an F7R conversion in mind for the not too distant future and would like to see all the information on the two F7R variants compiled and debated in one thread - perhaps it can serve as a sticky for all people after the same information?

Basically what I personally would like to know, is what the main differences are between the F7R as found in the Clio Williams and the F7R in the Megane Coupe. If memory serves the differences are primarily in the specification and design of the head, but what performance characteristics are borne from those differences?

Would also be interested to hear what people have to say in favour of one engine over the other and any general pros and cons for each one.

Cheers guys,

Ben

Forum Moderator Joined: 18 Feb 2004 Posts: 7432

Stan and JB will have the main input here but since theyre sitting in a car on the M4 and im not, ill start Smile

in a nutshell, performance wise, they have the same peak power, but the megane engine has a slightly broader torque curve.

In terms of nitty-gritty detail, the megane head has smaller inlet ports and bigger inlet valves. The cams in the megane are also milder for some reason or other, according to stan and JB.

There's more work to be done to get the megane engine to fit in a 19 unless you want to fit the whole megane loom and management. Basically you need to get the head machined to run the dissy and fit the flywheel from the 1.8 if you want to run the 1.8 management (preferably remapped to suit).

Only other thing to think about for the 19 application is the exhaust. The clio manifold and downpipe wont fit the 19, but the megane one will apparently, although you still need to bodge something up to make the downpipe mate with the rest of the system.

Thats about it tbh.

Site Subscriber Joined: 07 Oct 2004 Posts: 2281

I thought the F7P's exhaust manifold was the same as the F7R's?

Shows what I know!

Forum Moderator Joined: 18 Feb 2004 Posts: 7432

no the F7P has a cast one, F7R has a tubular effort. You can use the cast one on the F7R if you want and it will work fine, but its not the ideal setup in terms of torque characteristics.

Site Subscriber Joined: 07 Oct 2004 Posts: 2281

So an uprated F7P manifold would be the easiest compromise then?

Forum Moderator Joined: 18 Feb 2004 Posts: 7432

well, it depends on what you mean by 'uprated'. If you mean a tubular one that has been optimised for the 1.8, then no, that wont be ideal for the 2.0.

The 2 engines have different characteristics and their corresponding manifolds have been designed to suit.

ie, the 1.8 is very revvy and has quite poor torque low down, so the manifold was designed to try and gain some torque back at the lower end.

The 2.0 on the other hand is not as revvy and has more torque lower down, therefore its manifold was designed to try and grab some more torque higher up.

If you fit the 2.0 tubular manifold to the 1.8, you can see that the already relatively poor low end torque will be sacrificed even further.

The above is all in theory though, and people who have mixed and matched have said different, and are often pleased. Depends what youre after really.

Site Subscriber Joined: 07 Oct 2004 Posts: 2281

Well, the idea behind the Williams conversion was to get at the torque that the Valver lacks! So this means I'd need to try and use a Williams manifold, but if that ain't gonna fit and people have mixed and match and been pleased, then maybe some trial and error is in order.

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

1.8 manifold gives better low down torque than the willy/megane unit.

Willy engine easy swap, megane swap far more involved. I advised mickpm on how to do it for leannes 19.

Mr Quoter-vator Joined: 16 Feb 2004 Posts: 7405

jimbo did have a williams zorst manifold in his 19 for a while...didnt like and returned to the cast one....but it did fit..cannot rememer if he had some custom downpipe to bridge the gap...

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

16V exhaust, 16V manifold theres no gap to bridge

Mr Quoter-vator Joined: 16 Feb 2004 Posts: 7405

williams maniold

Affiliate Joined: 28 Jan 2005 Posts: 360

Ben, the F7R-710 (Megane lump) will (as already stated) go straight in to the 19 but if you are unlucky enough to have ABS (Like we have) the pump will have to come out of the way to squeeze the new lump in without destroying it. We decided to run the coil pack ignition rather than have the head machined to accept a distributor and as we'd always planned to do the dash conversion we also opted to run the Megane's management as it was the logical thing to do but it wasn't that easy and we had some great fun making it all work. ChrisH, Neil Tunney and the guys at Renault Nottingham (purely for Dialogy's and wiring schematic access) were all a huge help to us on our conversion as loads of custom wiring was required to make Megane management and 19 hardware co-exist... it was emotional at times but our early trips up the road seem to point to it all being worth while as you can feel the differance without giving it death! As someone has pointed out, the exhaust systems are differant on the 1.8 as opposed to the 2.0. We opted to go with a decat Megane system and make it meet the 19's original setup in the mid section as the 1.8 manifold really isn't up for the job but if you go ahead the choice is yours about going for a Williams or a Megane. Other things to bare in mind is the 19's front engine mount and the power steering resevoir! The Front engine mount will have to be retained as the Megane Coupes use a top mount as found in the Clio's and unless you want to be welding in a custom mount it's far easier to get the 1.8's altenator bracket and use that. Also, the radiator is nearly twice the size on the Megane Coupe compared to the one on the 19 and due to it's design you will need to reloacte the resevoir for the power steeering.

There is (So i have heard) an F7R-714 but I've no idea where they come from and the only thing I can think of is it's possibly the F7R lump used in the Renault Spider which is designed to take a gearbox for a mid engine chassis rather than a traditional FWD setup - I'm sure i'll be corrected if i'm wrong on that. Anyway, come have a chat and a good look at our 19 at Donny, Nationals or FCS if you like.

Mick

PS: Chris - when you gonna get your ass to a show so I can finally meet the Renault Supreme being and buy him a beer?

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

when a show comes to a central scotland area Very Happy

Gay Rights Activist Joined: 07 Apr 2004 Posts: 1268

F7R 714 was fitted in megane 2.0 16v's from 97-99. Basically the same as 710, but the oil pump is driven off the crank like on the 172. also different shape sump.

Site Subscriber Joined: 07 Oct 2004 Posts: 2281

Cheers for the info guys, its all good!