182
Hi all,
I was curious to wt the diffrences were between the 182 head and the 172 as ive been told fittin the 172 wud give me more power ?
Also i was thinkin of gettin the Inlet Manifold reworked (angelworks) but then found this in a perfermance french car mag (not sure if it affects me gettin the reworked inlet or not):
PORTING, POLISHING AND MATCHING
Q.
I want to have a go @ modifyin the cylinder head and manifolds on my clio. Ive read quite alot on the subject and cnt figure out which ports i should polish and whether theres any benefit from matchin them. Can you clear this up for me and advise me on the best mods ?
A.
Theres alot of diff opinions on how to mod a cylinder head and whether the ports should be matched. We've spoken with several cylinder head specialists on the matter and they all seem to come up with the same advise. The inlet ports should not be polished, but rough. This helps to agitate the mixture of fuel and air as it passes into the port. A polished inlet port allows the droplets of fuel to settle instead of mix with the air. An exhaust port, however, can be polished. This will help to extract the exhuast fumes.
Matchin the size of the ports to the size of manifolds is sumthin that shud be avoided. The reasons are easy to understand. On an inlet port and manifold, the mixture of air and feul needs to be drawn into the headas the piston moves down in the engine block and the inlet valves are open. Once the piston starts to move up in the engine block, the inlet valves may still be open. This can cause the air and feul in the inlet port and manifold to be pushed out and back towards the throttle body or carb. If these fumes become ignited, this can cause an explosion in the inlet manifold or further back up the induction system. To ruduce the risk of this happening, ensure the size of each inlet manifold is smaller than the size of the inlet port. Any air and fuel that gets pushed back will be obstructed by the smaller opening of the inlet manifold.
The exhaust manifold has a similar issue. You dont want exhaust fumes being sucked back into the engine, so the manifold must be larger than the exhaust ports to form an obstruction.
Many Thanks
I was curious to wt the diffrences were between the 182 head and the 172 as ive been told fittin the 172 wud give me more power ?
Also i was thinkin of gettin the Inlet Manifold reworked (angelworks) but then found this in a perfermance french car mag (not sure if it affects me gettin the reworked inlet or not):
PORTING, POLISHING AND MATCHING
Q.
I want to have a go @ modifyin the cylinder head and manifolds on my clio. Ive read quite alot on the subject and cnt figure out which ports i should polish and whether theres any benefit from matchin them. Can you clear this up for me and advise me on the best mods ?
A.
Theres alot of diff opinions on how to mod a cylinder head and whether the ports should be matched. We've spoken with several cylinder head specialists on the matter and they all seem to come up with the same advise. The inlet ports should not be polished, but rough. This helps to agitate the mixture of fuel and air as it passes into the port. A polished inlet port allows the droplets of fuel to settle instead of mix with the air. An exhaust port, however, can be polished. This will help to extract the exhuast fumes.
Matchin the size of the ports to the size of manifolds is sumthin that shud be avoided. The reasons are easy to understand. On an inlet port and manifold, the mixture of air and feul needs to be drawn into the headas the piston moves down in the engine block and the inlet valves are open. Once the piston starts to move up in the engine block, the inlet valves may still be open. This can cause the air and feul in the inlet port and manifold to be pushed out and back towards the throttle body or carb. If these fumes become ignited, this can cause an explosion in the inlet manifold or further back up the induction system. To ruduce the risk of this happening, ensure the size of each inlet manifold is smaller than the size of the inlet port. Any air and fuel that gets pushed back will be obstructed by the smaller opening of the inlet manifold.
The exhaust manifold has a similar issue. You dont want exhaust fumes being sucked back into the engine, so the manifold must be larger than the exhaust ports to form an obstruction.
Many Thanks
