Throttle body modofication

Any form of normally aspirated power mods.
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Throttle body modofication

Post by Just_Jack1991 » Mon Jun 20, 2016 11:48 am

Hello everyone, please don't hate, I'm just sharing some knowledge from a different forum!

So back when I had my RenaultSport 200 (2liter one not the 1.6 panel shift model) I was also part of there owners club/forum, the guys over there were similar to here, either trying to squeeze as much power out of the NA engine or sticking the megane 265 engine in and being done with it (dam you Mazda for not making a turbo RX8 so this is an option!!!!)

The very last thing the guys found before I sadly parted ways with the forum and the car was polishing out the lips on the front and back of the throttle bodies, the reason for this is due to the disruption of air as it passes through the throttle body, if you first sanded back the lips so they were level with the curve of the throttle body and also sanded back the rough metal surfaces leading to the sleave that the butterfly sits in and then gave the whole body (as mucb as you can safely get to) a polish to a mirror finish then the increase in throttle response and the general "feel" of the car changed so much that some of the guys were actually second guessing an engine swap out with the megane engine.

Now I'm not saying anything against the thousands or even millions car manufacturers put into making everything work, what the guys over there found was mainly the cost involved in polishing each throttle body would be to high as a non polished one would work.

So here is my proposition, as our cars could most likely such the brass off of a door handle anyway, surely smoothing out and slightly increasing the volume of air which can pass through the throttle bodies wouldn't be a bad thing? In simple terms, more air in, more power out right?

Anyone tried this? And has anyone got any information or advise one way or the other as to why I shouldn't do this to my Rex tomorrow and get even more smiles per gallon?

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Re: Throttle body modofication

Post by joney » Mon Jun 20, 2016 1:05 pm

Yer it has been done been thinking of trying it but not had the time
If its not broke I'm sure I can find a reason to take it apart :thumright:
Things Done: Nexus Mod, Led Lights, D969 Coils, cobra exhaust, moded ash tray to gauge pod, Toyo Decat, cruise control mod with mazda 6 steering wheel and Lots of Cleaning
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Re: Throttle body modofication

Post by Cabbie » Mon Jun 20, 2016 1:17 pm

I have one for sale if you want to try it ... 46&t=70161

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Re: Throttle body modofication

Post by gibson1173 » Fri Sep 09, 2016 11:38 am

I did mine yesterday spent go hours or so grinding and polishing and wow yes has made the throttle response crisper and had made a little difference to the performance too :D

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