Tim@TBDevelopments
Lifer
This was a revisit to a customers engine I rebuilt about 12 months ago, This was a simple job, engine was provided with bent conrods, cracked pistons from an overboost and hydolock-up 
so this was all rebuilt to his specifications, engine had been run in properly and all was good. But i received a phone call from him saying that the car had been mapped by a "well known mapper" and the first time he had used the car to its full potential, it had blown he said it had lost compression, sounded like a tractor and sprayed oil all over the bonnet. So standing by my engine builds i said bring it back and we'll go through it together. So a few weeks later when was convenient for David he brought the engine down and we went though it together. He had informed me that the engine was perfect until this fateful day after mapping when it blew.
My first suspensions to something being wrong with the map happened when the spark plugs looked like this.
We went further and striped the head off, and found all pistons in a poor state, Detonation pits all over them, the very thin metal at the edges either melted away, or very distorted because of the heat, and then the cylinder that had 0 compression.
This was BAD
Looking at the metal that looks like its been made from chocolate and someone put a blow torch it confirms the engine had been running extremely lean and puts the failure down to the mapper.
You can even see where the metal had been getting so hot when it finally failed it blew molten aluminium all over the inside of the opposite piston skirt, this is also all over the conrod and down the bores of the cylinders (I'll get pictures of that)
After a discussion on how it was mapped, it was revealed to me that the mapper didn't use "det cans" when mapping so there was no way of picking up detonation properly, but also more shocking that it was mapped using his own On dash lambda sensor, which david said to me was basically a £20 ebay gauge that's wired into the stock O2 sensor. so this would only be displaying in narrow band format. This is shocking.
Well because of this failure and evidence the engine has been left with me, funds won't be available for a full rebuild for a few months and the engine isn't need again until next summer so this will be shelved for now and the rebuilt carried out over the quieter winter months.
So look for updates. I'll take alot more pictures once i take everything apart in a quiet 5 mins.
so this was all rebuilt to his specifications, engine had been run in properly and all was good. But i received a phone call from him saying that the car had been mapped by a "well known mapper" and the first time he had used the car to its full potential, it had blown
he said it had lost compression, sounded like a tractor and sprayed oil all over the bonnet. So standing by my engine builds i said bring it back and we'll go through it together. So a few weeks later when was convenient for David he brought the engine down and we went though it together. He had informed me that the engine was perfect until this fateful day after mapping when it blew.My first suspensions to something being wrong with the map happened when the spark plugs looked like this.
We went further and striped the head off, and found all pistons in a poor state, Detonation pits all over them, the very thin metal at the edges either melted away, or very distorted because of the heat, and then the cylinder that had 0 compression.
This was BAD
Looking at the metal that looks like its been made from chocolate and someone put a blow torch it confirms the engine had been running extremely lean and puts the failure down to the mapper.
You can even see where the metal had been getting so hot when it finally failed it blew molten aluminium all over the inside of the opposite piston skirt, this is also all over the conrod and down the bores of the cylinders (I'll get pictures of that)
After a discussion on how it was mapped, it was revealed to me that the mapper didn't use "det cans" when mapping so there was no way of picking up detonation properly, but also more shocking that it was mapped using his own On dash lambda sensor, which david said to me was basically a £20 ebay gauge that's wired into the stock O2 sensor. so this would only be displaying in narrow band format. This is shocking.
Well because of this failure and evidence the engine has been left with me, funds won't be available for a full rebuild for a few months and the engine isn't need again until next summer so this will be shelved for now and the rebuilt carried out over the quieter winter months.
So look for updates. I'll take alot more pictures once i take everything apart in a quiet 5 mins.