GHL EXHAUST CRACKS
01-11-2007, 01:43 PM
#77
Rennlist Lifetime Member
9 out of 10 are normally cracked. Just looking at them you can not see them. They are hairline stress fractures. When you bead blast them they are almost always there. I use to buy used heat exchangers, bead blast them, coat them and resell. But after all the bad sets with "low" mileage on them I gave up. The cracks are almost always on the crossover pipe and the turbo flange.
01-11-2007, 04:05 PM
#78
Three Wheelin'
Join Date: Apr 2006
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Stephen,
So if what you say is true about the standard headers too, then we are losing power when the cracks appear (assuming large enough for leaks). Therefore it would be worthwhile replacing every few years anyway.....
So if what you say is true about the standard headers too, then we are losing power when the cracks appear (assuming large enough for leaks). Therefore it would be worthwhile replacing every few years anyway.....
01-12-2007, 09:40 AM
#79
Burning Brakes
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Could it be that the cracks are due to metal fatique caused by long term repeated flexing of the pipes and joints/places perpendicular to the flex movement are the places most susceptible? This would happen if any part of the exhaust system (incl. turbo/wastegate/muffler) is attached to the car body (rather than the engine) as the engine moves relative to the body each time it is revved hard or hits a bump.
There are exhaust systems that use flex joints or flanges with sprung bolts to "absorb" this flex stress
There are exhaust systems that use flex joints or flanges with sprung bolts to "absorb" this flex stress
