Bonnet vent

Benn j

Gold Member
Hi guys
my 200 is off the road at the monent having the meg treatment .... No I'm thinking about a vent on the bonnet to aid cooling and obviously cold air to filter ect...
will I benefit from doing this? And obviously don't want water getting in where it shouldn't what are my options here?

Thanks
 
I wouldn't. Although Litchy runs a turbo, having a vent in his engine bay didn't make any noticeable difference to his temps.

The 197 copes well without one but knowing how fragile the electrics are, I wouldn't risk it ha
 
All decat and link pipe will be wrapped properly ect so hoping that helps with temp in the bay but just looking for that extra bit of cooling really. And obviously cold air going too filter.
 
I'd look at getting the decat, manifold and turbo hot side ceramic coated. Wrapping can get soaked with oil and become a fire risk.
 
I've also been thinking about adding a bonnet vent to my car as on track the temps really did start to rise.
Think I might have to get a larger radiator and try waterless coolant.
 
I'd be looking at alloy radiators first, I would be reluctant to start cutting holes in the bonnet.
My opinion.
 
Been researching the issue for two years now. Don't think the larger rad will solve it but might help. I think its water flow with the problem being a localised boiling issue. Megs don't have the same as I'm told the bulkhead is more bellowed and therefore better airflow. I'm told by Renault that they considered fitting the 225 engine but the problem was heat which they couldn't control in the Clio. That's why most of the conversions suffer from indiscriminate heat issues in the engine bay, with the ambient temps high just worsen the issue.
 
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Would a bigger water pump help. I know that early dolomite sprints had heat issues so to solve it they fitted the larger water pump from the triumph stag.
 
Water pump will be rated for the meg as it is. If your running the standard Clio rad, this needs to be changed out. A few weeks back a bloke at Blyton with a meg conversion was running and struggling with temps due to still retaining the Clio rad, this temp overcomed by bypassing the rad fan relay and putting on all the time. The mod I think is to improve rad and cooling to rad and cooling fans, as with wrapping the exhaust & turbo.
 
The bigger rad would help but I'm not entirely sure would solve it. Also not sure there's enough room for a bigger rad.
The engine bay is ridiculously hot especially when the ambient temps are higher and I'm sure it's harder for the heat to disapate out the engine bay than in the Meg. Stating the obvious but the issue clearly is related to the heat from turbo and I might have to look at cutting away the scruttle panel above the turbo to get more air out the engine bay.
 
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Hi guys, sorry to bump but I've been having a few temp issues on track (Meg swap).
After a ten min stint the temp goes over half way on the dials, and the induction cone was a tad too hot to touch.

Not sure what to do but I'll start with replacing the thermo stat, possibly a eBay 60mm FMIC. What else has any one found to work? People are saying raisers and bonnet vent?
 
Saw some threads on Pistonheads about using Water Wetter, gets positive reviews for actually doing the business. So on track and in the summer with a pure water mix it should help you out. However for a road car you'll want to switch it back out for a water/glycol mix come the wintertime.

Probably a poor substitute for just getting a nice custom built thick alloy cored rad in there though :wink: Seen some work by AH Fabrications recently that looked very nice (in pictures at least not seen in the flesh).
 
Saw some threads on Pistonheads about using Water Wetter, gets positive reviews for actually doing the business. So on track and in the summer with a pure water mix it should help you out. However for a road car you'll want to switch it back out for a water/glycol mix come the wintertime.

Probably a poor substitute for just getting a nice custom built thick alloy cored rad in there though :wink: Seen some work by AH Fabrications recently that looked very nice (in pictures at least not seen in the flesh).
I was thinking I'd need a new intercooler, was going to go with the tried and tested 60mm ebay jobby (£169!) but the AH Fabrication ones appear to be far superior quality and seem well priced too (still cheaper than airtec and forge by a chunk!).
 
Not sure if the Megane's cooling system is similar to Clio's but Renault Sport recommends R3 owners to increase water flow in the following manner:
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Not sure if the Megane's cooling system is similar to Clio's but Renault Sport recommends R3 owners to increase water flow in the following manner:

The cooling system consists of a mish mash of megane and clio pipes, that diagram is a cracking find cheers I'll look into it!
 
Hi guys, sorry to bump but I've been having a few temp issues on track (Meg swap).
After a ten min stint the temp goes over half way on the dials, and the induction cone was a tad too hot to touch.

Not sure what to do but I'll start with replacing the thermo stat, possibly a eBay 60mm FMIC. What else has any one found to work? People are saying raisers and bonnet vent?

What temp is "over half way"? also standard temp gauges are not very accurate...

a FMIC isnt going to reduce your engine temps btw, only your ACT's however i wouldnt expect to see a huge bennefit as the turbo is on the back of the engine and the intercooler on the front being fed with cold air, this is a more previlant benefit on cars that have turbos on the fron of the engine, RS Turbo's etc