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MG MGB GT V8 Factory Originals Technical - Rover P6 Rocker Box covers

I have just got hold of a pair of P6 rocker covers and hope to fit them to my V8 conversion. It is a SD1 engine with twin SU's. I believe there to be no real difficulties with the change of covers but does anyone know different. There isn't a flame trap on the P6 covers; is this a problem and the filler may have to go the other side.

are you using the factory V8 SU setup? if so youll need to find a new way to mount the air filter boxes as the rover covers dont have the mounting bracket holes. youll also need to modify the covers to accept the flame trap hoses in the center of the cover on the inside face like the factory MG covers. other than that they should fit quite nicely. im actually in the same boat if that is your situation, i have the factory setup and found a pair of rover covers but i think ill go with the repro MG covers because they wont need any modifications.

I am using the factory style inlet manifold with the carbs set at the back and an air box with K and N filters. How do I do the modification for the flame trap. The rocker cover have two breathers which I presumably take a feed off for the carbs. can I remove the flame trap from the SD1 rockers?

I have also just noticed that if you cut the plastic off the SD1 oil filler cap you are left with a stylish aluminium one which can be polished as I have just done. I'm sure all you experienced converters are aware of this but i just saved my self from buying a chrome one. If interested I can email a photo.

yeah i forgot, the SD1 rocker covers have the one tall flame trap instead of just a filler cap, right? anyways, if you have the original flame traps,(small gray ones, two of them) you can get some hose and plumb them right onto the breathers on the P6 rocker covers and the other side to the brass ports on the side of the carb, they angle up. would you like a picture of the original set up?

You might have crankcase breathing problems. The P6 engine had the breather inlet at the rear of the engine block & used the outlets on the rocker covers to direct the fumes into the inlet manifold.The SD1 engine used one of the rocker covers as inlet & the other as the outlet into the inlet manifold. I tried to adapt P6 rocker covers on a SD1 engine using the SD1 route but but the valley seals didn't last very long.I use a Holley not SUs, you might have more success than me. HTHs Barrie E
Barrie Egerton

Wait a sec, guys, this should work out fine for Steve -- just rig it the way that we 4-barrel guys do. With the P6 covers, just hook a PCV valve to one of the breather tubes and plumb that to your intake manifold. Depending how you've got 'em handed, it will be obvious which one should go to which. Hook the breather tube on the other cover to your air cleaner (that way, in high-vacuum situations where your PCV shuts, vapors are sucked down through the carb and you'll not be without a little suction on the crankcase ... which is what would cause valley seal problems etc.). Works fine; has for years and with any luck will continue to do so. What I'm speaking of is the same way you'd do it with the SD1 covers; most people just think the P6 covers are a tad more elegant in the engine bay. (Over on this side of the pond very few if any of us bother with those flame trap thingies, when the number of PCV valve varieties you can buy for under $3 is in the thousands!)

Jake, I would be very grateful for a photo of the original set up showing the flame trap arrangement.

Has anyone had crankcase breathing problems with P6 covers and SU's with KandN's.


Yes well I still have problems. I bought all the bits for the standard set-up which seems to have a fuel filter as a cranckcase breather and two grey flame traps. (Note UK spelling!) However, I cannot find a spot to connect the cranckcase breather, and I certainly don't want to take out the engine to find it!
Can anyone help? It looks quite easy to modify the rocked covers to accept the tubes for the flame traps and I can pipe them into the aircleaner.
T Green

I have just checked out an article by Roger Parker via the MGOC V8 conversion website and he reminds that the oil filler cap needs modifying/shortening if converting to earlier rocker box from SD1. Also, the parts to modify (i.e flame traps and breathers etc.)appear to be available from V8 Conversions in Farnborough, Kent.

Steve, you asked for a pic, I have one and will try to send it to you by e;mail. Do you know where crankcase breather connects?
T Green

steve, i found a picture of the BV8 SU setup with the rover P6 rocker covers, if youd like to see how its set up, let me know and ill forward you the picture.

This thread was discussed between 27/07/2002 and 01/08/2002

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