S1 2.8 manifold bolts etc
Discussion
Alan461 said:
Got 30mm long stainless cap heads on mine, not sure if it's ok to use stainless but seem to be ok
caphead bolts certainly look alot tidier, I was considering stainless or titanium? Gotta be an improvement from the originals that end up caked in brown rust & corrodedEdited by greyhulk on Thursday 9th June 18:51
I have also used stainless, both for the manifold to block bolts and the manifold to pipe. But I did take care to get hold of the higher tensile option and I did use Copperslip on the manifold to block bolts. I used Hex but I should have used hex socket and will do on the 'new' engine.
Anyone using the original cast manifolds might wish to be aware of one modification that can be made. The studs in the end of the manifolds get in a bad way and getting them out when the threads are gone can damage the flange. In addition the flange is pretty vulnerable if the exhaust takes a hit, which it does pretty often on the S1. When I had the manifolds off I took the opportunity to use heat on the studs and get them out. I then drilled out the stud holes a size larger. I now have stainless hex socket screws (and double nuts)right through the manifold and pipe flanges. As they are one size undersize they do allow a little bit of shock movement without damage, and indeed I have seen evidence that they have allowed such movement without even breaking the exhaust gas seal. B....y sight easier to het undone too!
Anyone using the original cast manifolds might wish to be aware of one modification that can be made. The studs in the end of the manifolds get in a bad way and getting them out when the threads are gone can damage the flange. In addition the flange is pretty vulnerable if the exhaust takes a hit, which it does pretty often on the S1. When I had the manifolds off I took the opportunity to use heat on the studs and get them out. I then drilled out the stud holes a size larger. I now have stainless hex socket screws (and double nuts)right through the manifold and pipe flanges. As they are one size undersize they do allow a little bit of shock movement without damage, and indeed I have seen evidence that they have allowed such movement without even breaking the exhaust gas seal. B....y sight easier to het undone too!
Alan461 said:
Got 30mm long stainless cap heads on mine, not sure if it's ok to use stainless but seem to be ok
You might struggle getting an Allen key into some (all?) of the bottom bolts?Can be difficult (impossible?) to get a ring spanner on normal M8 bolts with 13mm head in one or two places so I went for M8 bolts with a 10mm head
.............. clickyAs always great advice gents, appreciated.
So I'm looking at 8, M8 (1.25 thread) x 30mm bolts, think i will be going with Mr Phillpot's link saves me searching around on evilbay.
Just remembered the manifolds come with the downpipes too, I'm guessing there's a further 2 gaskets I've forgot about there an another 4 bolts?
So I'm looking at 8, M8 (1.25 thread) x 30mm bolts, think i will be going with Mr Phillpot's link saves me searching around on evilbay.
Just remembered the manifolds come with the downpipes too, I'm guessing there's a further 2 gaskets I've forgot about there an another 4 bolts?
phillpot said:
You might struggle getting an Allen key into some (all?) of the bottom bolts?
Can be difficult (impossible?) to get a ring spanner on normal M8 bolts with 13mm head in one or two places so I went for M8 bolts with a 10mm head .............. clicky
Forget all that.... forgot yours is a 2.8 Can be difficult (impossible?) to get a ring spanner on normal M8 bolts with 13mm head in one or two places so I went for M8 bolts with a 10mm head
.............. clicky
I was about to say wait a minute im sure yours has different manifolds to mine, isn't Alan's an S2 aswell?Although things are indeed a bit different on the 2.8, Mike has however made a worthwhile point. It might well be sensible to have different fixings at different locations based as much on access as anything else. There is no reason they have to be the same, it is not as if we are looking at quick release with limited tools.
That said the titanium bolts do look and sound cool!!
That said the titanium bolts do look and sound cool!!
One of the recurring problems with the V8 is that the manifold flanges aren't thick enough to get a decent amount of stretch on the bolts to cope with thermal expansion. If you're starting from scratch it would be worth thinking about using longer bolts (with sleeves between the bolt head and the flange). I assume that would change how accessible the bolts are - would it change it for the better?
Kitchski said:
M10 studs/nuts on an exhaust manifold chaps, on the 2.8 anyway.
Really? Manifold to head? WOW! That has really surprised me, never seen any car with larger than M8 or 5/16" on old stuff.I am not saying you are incorrect as I have never worked on a 2.8 but, WOW!
Stunned,
Carl.
Just to confirm, the threads in the heads of a 2.8 where the manifold is secured are M10 x 1.5. The originals are studs but I have changed mine and one of the other engines I have also has bolts. The bolts are 30mm under the bolt head and 16mm hex on the old one in front of me now. I have checked 3 sets of heads and they are all M10. I have a horrible suspicion however that the very early Cologne engines might not have been the same so there may be a few heads around on S's which differ.
greymrj said:
Just to confirm, the threads in the heads of a 2.8 where the manifold is secured are M10 x 1.5. The originals are studs but I have changed mine and one of the other engines I have also has bolts. The bolts are 30mm under the bolt head and 16mm hex on the old one in front of me now. I have checked 3 sets of heads and they are all M10. I have a horrible suspicion however that the very early Cologne engines might not have been the same so there may be a few heads around on S's which differ.
Very helpful as always, thanks gents, made a note of what I need now (got a 4weeks wait on the ss manifolds *sigh*)Gassing Station | S Series | Top of Page | What's New | My Stuff