The Jensen Owners' Club

Damn.

Your doesn't look that low. What tyre size are you running?

Vredestein 205/70s. The car is maybe a bit lower than standard. Without passengers or luggage I clear the bump.

I tied the manifold together with wire and wrapped it with tin foil, hoping to reduce the fumes in the engine bay and also to dampen the noise. Seemed to work well at first but the tin foil didn‘t hold up too well after all, but it was a 50 minute drive to Andi‘s. I hope those metal flakes can be removed, otherwise I‘ll have to cover the rest of the engine bay with glitter also.

Before: After:

Those tyres lower it by 19 mm.

I would suggest to check the rear silencer mounts and engine mounts as a possible contributor to the break. Engine mounts because a soggy mount allows the exhaust down pipe to droop and a broken mount allows it to hit the footwell floor. Also looking at the cracked manifold in the first picture, the downpipe has sagged several inches when the manifold broke. I like to have my downpipe such that the rear mounts give enough support to keep the downpipe just touching the manifold flange when there are no bolts fitted. This way under normal conditions there is no stress on the manifold. If the exhaust is dragging the manifold down the gaskets keep blowing (if you use them, I don't) and as the manifold is heating and cooling and being hit from underneath it has this constant force pulling it apart exactly where it finally broke. This could have been stress damage building up over years, or in my case months until I finally fixed the brackets. I am sure Jensen were thinking of this at least on the Mk1 Interceptor because if you look at the rear silencer mounts there are height adjustable brackets fore and aft, with lock nuts to stop up and down movement.

Thanks guys for your advice, much appreciated! I think the manifold may have already had a hairline crack before the incident.

Picked the car up late last night- Andi mounted new cast iron headers from Robeys. When Andi and I were speaking of mounting new ones I had assumed they would be stainless steel ones, I didn't know that Robeys had new cast iron ones. John, to answer your question: as I gather it is not impossible to get the veteran MOT with stainless steels ones, but it is risky.

Were both manifolds cracked?

Rohan Christmas wrote:Were both manifolds cracked?

Don't think so, no... Are you wondering why we replaced both of them? Swiss way of doing things I assume Seriously, last time the manifold broke was 2017 at the Germany meet (on the Autobahn) and I had to get the car transported back to Switzerland. Enough is enough...

Just spoke to Andi: the manifold did not break along the existing crack. Comforting in the sense that I was blaming myself for not replacing the manifold when we noticed the crack...

The new manifolds have a more substantial look about them, perhaps an improved material? There are also bosses on the new ones for a heat shield. It would be interesting to monitor under bonnet temperatures, and then fit an etched stainless "Jensen CV8" or some such heat guard and see if temperatures around the wiring harness and brake servo are kept lower. Plug leads seem to hold up well these days. Here is an FF manifold for comparison with the original heat shields fitted either side of the downpipe flange.

Trackday organized by Friday Classic at the Anneau du Rhin 2019 (https://www.joc.org.uk/forum/viewtopic.php?f=2&t=29356" onclick="window.open(this.href);return false;)

Went filming today on the Klausenpass. Just as we were finishing up (after 4 hours), the drone got caught in one of the trees below the car on the first picture- with all the data in the drone... Waiting for a mountain climber to come and see if we (he!!) can recover it...

Good luck!

Are those barriers stronger than they look?

Thanks Stephen. Not sure what those barriers are for, many have died there. Two locals got the drone for us- hanging in a tree over a really spooky drop. I‘m terrible afraid of that road and had to do it 8 times today for the shoot, and spend another 3 hours there because of that bloody drone...

Man Alive.. how the hell did you find that loony Felix?
He's so brave and a blessing for you, please pass him this>>, and one for you too Felix for finding him