Need advice on manifold gasket

[306Puggy]

As it happens I replaced the manifold gasket about 6 months ago when it was fine anyway (the fuel filter turned out to be the problem) but I am worried that as a nut and spacer have fallen off one side this has allowed the gasket to break apart and I will have to do it all again. In the case of me having to do that I would like to know whether a fibre gasket or a steel gasket is better. The gasket I used last time was fibre and it is now obviously blowing as a result of losing a spacer (I think). The reason I think it is blowing is because in this pic you can see some coal around the manifold (circled):

I was hoping a steel gasket would be more robust and able to hold boost better (when I can finally start tuning again). Also what grade of sandpaper should I use for cleaning the flanges and the block surface? Last time I used 80 grit which I think was a bit too severe but it was all I had available. I was thinking maybe 280 or something?

[Piggy]

I use 400 for surfaces like that and metal gaskets too. 80 maybe at first just to get the thick crap off...but 80 is pretty harsh.
Ensure its wet and dry stuff and use it wet or even better with some wd40/doubleTT

worth noting that you are missing a inlet mani bolt there...just to the right of the red circle!!!!

[Chris_90]

defo looks like the bolt missing from the inlet manifold carnt be doing you any favors, I used steel gasket no issues as of yet

[bigcheez2k3]

I used a fibre one on mine last week that I got from Pug, but pulled a metal one off. Was curious why the difference but my mate said manufacturers update the design so it must be better.

[306Puggy]

As it turns out it had blown. Cleaning the coal off the cylinder head side was a NIGHTMARE. I couldn't see anything at all. It took loads and loads of rubbing and about 6 sheets of sandpaper to do, all fully lubricated with soapy water ofcourse!



All done, heh:







Horrible job though, took 2 and 1/2 days including the horrible sandpapering that I had to do.

[Dave]

This is certainly not a good idea, you end up creating high and low points on your mating surfaces. Only do this with a block of long flat block of wood behind the paper to emulate a flat surface

[cully]

This is certainly not a good idea, you end up creating high and low points on your mating surfaces. Only do this with a block of long flat block of wood behind the paper to emulate a flat surface

this^^

or if the item is removable wet and dry on a sheet of glass
or you could use grinding compound and lap the two mating surfaces together
done this a few times with 2-stroke engine heads