Engine upgrading

[Azazello]

So it's time - my head gasket definitely failed, and my engine is being stripped by my mechanic for a total rebuilt. It's more than 220k km old, so I expect even other parts are needing work, and I want to end up with a reliable car, after all that work.
I am planning to "enlarge my engine", as Angel told me as a possibility instead of switching the engine with a bigger one (so the code on the engine remains the same and no-one would notice the difference, since this work is quite illegal here).
My 956 engine could be transformed, I was told, in a 1108 one using rods and pistons of a GTL or in a 1239 using rods and pistons of the earlier twingo... Do you think the last hypothesis is a convenient work?
Or I will end up with a thirsty car?
I have some doubt even on the gearbox to couple with those engine: the twingo engine has the maximum power of 54hp at about 5300 rpm, so I wonder if it prefers the tl gearbox instead of the gtl one...
While if I fit the GTLized engine I will need a longer-ratio-gearbox, because of the lower max rpm of the engine...
Great doubts!
I am going to invest quite a big amount of money, and I would like to choice the better way, in terms of power, noise, consumption and drive comfort...

 

[pepper]

GTL gearbox to keep , it has the longest fourth gear, which you'll need to keep your economy down and to keep it quiet(ish) on long journeys!

If I were you I'd try and keep the engine as standard as possible, I have a friend who has modified and had modified for him Volkswagen and Morris engines, without fail tehy have all caused him grief and very expensive pain, I very rarely try and have an engine rebuilt, I will try and get a good second hand engine and just put that in.

 

[Azazello]

I think I will end up with the standard 1108 engine, just fitting new rods and pistons and skimming the head as Angel told me. And I have to find the gearbox too!
The twingo engine has an electronic ignition and no carb, so I think it is no so predictable how it would work in a r4 setting...
Thank you for the advice!

 

[politeperson]

TL v's GTL Tuning and Gearbox Ratios

I have had experience of both these units as attached to the 956cc and 1108cc cars respectively.

Hypothetically there should be some difference between them.

In reality there is not much in it at all. Both drive nicely on the motorway.

The earlier cars are another story in my opinion, (lovely though they are).

I am sure their must be some difference in RPM at 70 mph, however there is so much difference between any later R4 and a modern car, that arguing the tiny difference in these ratios is is fairly pointless.

If you have a good gearbox condition wise, stick with it.

On the subject of tuning, the 1108cc/956ss motor is tricky as it was built for lightness, the castings are thin, so it is difficult to do much head work etc.

The Renault 5 GTL pre-85 inlet manifold/carb set up seems the easiest route, but I havent seen one for yonks.

I have built a "special" 1108cc engine with a Kent Cam many years ago. It revved and was fun. Cant remember the carb I used. It would cost about £700 to do now.

This subject of tuning has been covered many times on the forum.

However, I recently purchased a head gasket set for a pre 1108cc R5/R4 and I noticed it also fits the early Clio as listed on the packet.

I therefore wonder if this head will fit an 1108cc engine with a bit of fettling giving fuel injection. Or maybe the later R5 head.

I looked at a picture of an early Clio motor, the dizzy appeared to be in the wrong place and the manifolds were for a transverse set up, but maybe?

Anyone got any ideas?

 

[Eoynteenie]

its the twingo business that gets me...

 

[angel]

You will not need to swap connecting rods, only cylinder liners and pistons.

The largest liners these blocks can accept are the 1108cc ones. I'm not sure if the block and Twingo liners can be machined to fit, but it would be a waste of time and money, it would be more practical to fit a 1289 R5 engine.

Make sure you bring the compression ratio to GTL's 9,5:1 by skimming the head. This needs a mechanic / engine shop with knowledge on how to measure combustion chamber volume accurately, and on how to calculate the amount to be taken off the cylinder head.

Politeperson, the "early Clio" engine you refer to is the same as used on the early Twingo. The dizzy is not on the wrong place, but everything else is! I got such an engine, and by checking it side to side with an R4 engine, it seems that it can be converted for inline use. It will need extensive modifications like lengthening the camshaft and changing the coolant flow in the head, but I think they are easier than trying to fit Twingo liners in the R4 block. I will keep you informed as soon as I start this project.

 

[Azazello]

The 1108 engine is my final choice.

I've said about the compression ratio to the mechanic, now I have to trust him... He is going to send the engine to a professional shop that will completely strip down my engine and rebuild it, for the "cheap" price of 1215 euros taxes included.

 

[Azazello]

What will happen if I end up with the wrong (lower?) compression ratio?

 

[angel]

Nothing horrible, as the F6 engine actually had lower compression ratio. You will have slightly worse fuel economy ,and supposedly lower output (on the F6 engine, however it was the same 34 HP, so this may not be the cause).

Does this "cheap" price include the parts as well?

 

[Azazello]

Yes... New, pistons, liners, valves, valve seats (hardened because of the gpl), all gaskets,bushings and other stuff I do not remember (and maybe I do not ever know what role have in an engine).
I have to add the mechanic's work, new chain, and other bits... we have to see if it's time to change clutch, too... I think (hope) I will end up spending about 1500 euros.
And the new gearbox, of course.
And I have to change front brakes, too... even disks. They're making an awful noise and are not working properly...
Very expensive times...