cracked manifold

[marcus1970]

Have seen several posts on here recently about cracked manifolds and decreased performance. How can you tell if your manifold is cracked - idiots guide please.

Regards MB

[david smith]

when I looked down from top of engine bay past air box and body I could see the hairline crack on drivers side ... with airboxes off you can see more clearly... but I had not detrimental running because of it! - cracks were quite bad on both sides .. DAS

[Nickccc]

Hi,
I have recently suffered from this problem,
As you will know the AJP8/Speed8 is quite a noisy engine.I could not honestly say how long mine was cracked for, I did however notice a ticking, sometimes tinkling sound. It seemed to be coming from the engine sort of behind the dash. This has now gone so if you have this it could be a sign.
Also the Cerb software will probably be showing an AFR fault on the effected bank mine was.
Nick.

[Pete B]

Just yesterday we found a crack on each of my manifolds, we also found a crack in the same area on a spare manifold.
Is this a common fault on these ?(4.2 cerb) I showed the spare manifold to a specialist in pipework, mainly bikes, he was shocked at the quality of workmanship of the manifold and quoted me for making a pair of manifolds to a much better quality than the origonals.
I'm relunctant to have the existing ones welded up or replace them with a pair of "TVR" manifolds, if there only going to crack again, I've been told it's a pig of a job to change them, this in mind I'm thinking you may as well do it once-do it right.
Any comments would be welcome.

>> Edited by Pete B on Thursday 1st September 00:27

>> Edited by Pete B on Thursday 1st September 00:28

[simonsparrow]

My 4.2 manifolds also cracked, I got them replaced by 4.5 ones which are slightly bigger bore and apparently a little more resistant to cracking.

I've heard that ACT are thinking of producing some replacement manifolds, might be worth contacting them.

I also wish that I'd had my new manifolds ceramic coated, in order to reduce heat build up.

[Hughesie2]

simonsparrow said:

I also wish that I'd had my new manifolds ceramic coated, in order to reduce heat build up.

Does that not just send the heat problem into different areas of the exhaust system ??

[simonsparrow]

Hughesie2 said:

simonsparrow said: I also wish that I'd had my new manifolds ceramic coated, in order to reduce heat build up. Does that not just send the heat problem into different areas of the exhaust system ??

I'd do it more to get rid of radiated heat from the engine bay. A few people have had it done, makes the inside of the car a little cooler too.