More power for an 1108 R4 GTL

[Eccles60]

I gather replacing the carburettor and inlet manifold on my 1986 GTL with the parts from a Renault 5 (or 6?) will release 10 to 12 more bhp. Is this true? Do I need anything else? Are the bits out there somewhere?

 

[Jnr-Renospeed]

You can buy an Autobleu reproduction sports exhaust manifold - but they are not well made and are a b*stard to make fit, I'd be dubious as to whether they improve performance at all judging from the quality...
A larger more free flowing exhaust system from the manifold back will give you more ponies and a fruity tone but a custom larger diameter system is fairly expensive to have made.

Other than that there isn't much 'bolt on' stuff you can do other than the R5 hot up kit... maybe experimenting with carb jets, ignition timing and an 'Italian tune-up' would help, but the R5 conversion makes a significant difference on it's own, my Mums car leaves my standard 4 for dust even in normal driving so you should be happy with the result!

 

[Eccles60]

Many thanks for your reply JR. It looks like you're agreeing that the R5 inlet and carb is the most reliable way to go, but where might I get the parts? Renault 5s aren't exactly commonly available in scrapyards these days.

 

[Jnr-Renospeed]

My mistake I assumed you had the R5 conversion parts already. You'll find no luck in a scrapyard, you could see if any Fouristes or specialists are selling the full kit.
Occasionally parts crop up on Ebay, but Leboncoin would be my best bet for finding parts though it is difficult liasing with sellers because of shipping difficulties to the UK.

With the standard Zenith 28IF carb, you can restore some performance by drilling the main jet to 1mm, and doing a carburettor rebuild as the butterfly spindle seal can shrink and cause the engine to run lean over time. The set with the seal can be found below:

Revisiesetje carburateur Zenith 28 IF serie INCL. gasklepkeerring

www.renault4onderdelen.nl

 

[Praedo]

I’ve got most of the parts needed for this upgrade….zenith 32 carb, manifold, rocker cover, air filter for the carb etc. I lived in France and they’re quite easy to get on Leboncoin. I bought the parts to upgrade my 1108 engine and just didn’t do it. Bought the parts back with me when we moved back. There’s also a guy on lbc who has fabricated a kit so that you can bolt on a 32 carb without having to change manifolds etc. I’ve got a friend out in France and he lets me buy from lbc, ship to him and then he sends over to me.

 

[JdeW]

Double 32 mm weber carburetor, change the camshaft, install an Alpine atmospheric head, create a tuned exhaust.
Better to change the engine, try finding a C1J 784 or a 840-30