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MG MGB GT V8 Factory Originals Technical - Crankcase breathing
|Hi again |
Now I have my V8 rebuilt I want to try and sort the crankcase breathing out.
At present I have range rover rocker covers with the flame trap plumbed straight in the bottom of an air filter sat on top of a edelbrock 500 carb. On the other cover there is a little "mushroom shape" with 1/16" hole in it.
I have searched the internet and cannot find a definitive answer to how i should plumb this up with my carb.
Any suggestions please
We covered this in the other thread and I posted a picture of the set up of the PCV system.
Have you taken the bafffle off inside the cover and made sure that it is not gunged up.
Have you changed the rockers for the correct alloy ones, otherwise the excess oiling will still be a problem.
Alloy Rover rockers.
yes I have now fitted the alloy rover rockers
I just want to get the breathing right and there seem to be so many opinions on the set up
are you saying that the pcv is definitely the way to go as some people seem to go with less complicated set up
Glad to hear you've swapped to th proper rockers, hope you got a full refund on the others.
Re the crankcase venting, yes the system I described is correct as V8 engines seem to create a fair amount of pressure.
All you need is a filter open to air for one cover and slot in a PCV Valve in line on the other cover, you can retain the venting into the air cleaner if you want to, but I prefer to connect to the centre carb port as this will give more vacuum.
The reason this is important is that any blow by past the pistons which contain both exhaust gases and some unburnt fuel are scavenged from the system which reduces contamination of the oil and reduce crankcase pressure will improve prformance of the engine.
|I will order a valve|
thanks for explaining that as i was getting a little confused with all the different ideas on the internet
unfortunately I can't send the rockers back as I have had them for a while - you live and learn
|I started off with; 1) a filter on one rocker, 2) a pipe from each of 2 flame traps to the air filter, via a "T" connector.|
I had a bit of an issue with feeding oil fumes into the filter so fed the pipes into an oil catch tank. The result was quicker throttle response and cleaner filter. The MGBV8 had both rockers vented to the SU's and a filtered breather pipe from the cam valley. I was talking to a V8 engine builder who had seen oil seals blown and the valley gasket "flapping", due to insufficient crankcase breathing. So I went "belt and braces.
This thread was discussed between 13/11/2009 and 18/11/2009
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