Exhaust manifold stud measurement

[Kieron20V]

Probably not so easy on your kitchen floor though.... Hehe

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[Thuppu]

It's easy on the kitchen floor, but after when your wife has a metal chip in her sole it may be harder.

Pic:

[gmac78]

No gales or rain today so was moved location to outside the back door on a step, oh the joys!! Good progress made, all studs removed bar two which are WELL TIGHT, i was applying so much leverage that i'm surprised they didn't shear, heat applied and copious WD40 but no movement, i'll leave them to soak overnight and try again in the morning.

I'm liking the M12 tapped out with M8 in the middle, good idea!! I prefer that option to a helicoil actually. Since it's been done before with an M12 insert i'm happy that theres enough material in this area to open out.

I'm waiting for a valve spring compressor to arrive before i remove the valves, however i've started polishing the exhaust ports as far i can without removing the valves. Three done so far, two to go. Just using a few grades of wet and dry and some elbow grease and pleased with the results so far. I wonder how long the ports will stay polished for once up and running though.

Anyone dyno'd a car before and after head work, ie port and polishing, i'm curious just how much of a difference it actually makes?… Not that i'm doing porting, just going for polishing the exhaust ports and aligning RS2 manifold and gasket as best i can.

[newsh]

Mix a bit of ATF with some thinners, works much better than WD40. Engine oil and thinners works too or oil and parafin

[newsh]

https://www.youtube.com/watch?v=CESDxCloCoQ

[Michael S2]

Hi Guys,

Silly question here but none the less must ask.

I'm refurbing my 3B head and inevitably 3 exhaust manifold studs have sheared. Not to worry head is off so access is not a problem for repair.

However, the good studs that have been removed measure M8 x 50mm, where as, according to Vagcat they should be M8 x 35??

Now i'm confused as to what size i should order??

Is the 35mm measurement the amount that protrudes from the head when screwed in against the non threaded part? i assume it is but just want to be sure before i order the wrong ones.

I purchased 35mm m8 studs as I'm installing Wagner EM on my ABY. However, like you after removing my old studs they are about 47mm.

I'm going to order 47mm studs as this is a VW length apparently.

[Michael S2]

[tekstil]

35mm is the protruding part of the studs when they are screwed into the head. What you purchased is 35mm in total length. Order 8 of these 47mm studs and you might be able to use 8 of the shorter ones for the rest that you've already purchased. I did this very same job yesterday (Wagner EM to AAN head).

[Michael S2]

Thanks Tekstil, this is the first I've heard this clarified in all posts I've read on exhaust manifold studs. Maybe it's common knowledge. Now I know why studs seemed wrong. Thanks for your help. Good luck with your conversion.