Running 30%
11-12-2004 | 10:45 PM
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From: chesterton,
IN
RE: Running 30%
I only run 2 shims on 30% but if you run a bit and notice that the top of the piston is getting a little pitted then add another shim. The pitting is caused from detonation and thats bad, another shim should fix it if it happens.
11-12-2004 | 10:46 PM
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From: Palm Beach,
FL
RE: Running 30%
That is what goes between the head and the block, thanks. My lhs actually gave me glow plug washers[:@], but I took this one from a spare engine.
11-13-2004 | 12:26 AM
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From: , FL
RE: Running 30%
Detonation is the silent killer. It's a good idea when experimenting with different nitro %'s to take the head off an check the top of the piston often while going through the transition. Another tell tale sign is if when you switch and re-tune obviously that the motor runs a bit hot- then its probably detonating as well. Most race engines are shimmed from the factory to run at 25% nitro max as that is the max they are allowed to run in Europe. So I made it easy on myself and just run Trinity MHP 25% blend as does Byrons 2500.
11-13-2004 | 07:58 AM
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From: , VIETNAM
RE: Running 30%
ORIGINAL: SKYLINE350GT
Detonation is the silent killer. It's a good idea when experimenting with different nitro %'s to take the head off an check the top of the piston often while going through the transition. Another tell tale sign is if when you switch and re-tune obviously that the motor runs a bit hot- then its probably detonating as well. Most race engines are shimmed from the factory to run at 25% nitro max as that is the max they are allowed to run in Europe. So I made it easy on myself and just run Trinity MHP 25% blend as does Byrons 2500.
Detonation is the silent killer. It's a good idea when experimenting with different nitro %'s to take the head off an check the top of the piston often while going through the transition. Another tell tale sign is if when you switch and re-tune obviously that the motor runs a bit hot- then its probably detonating as well. Most race engines are shimmed from the factory to run at 25% nitro max as that is the max they are allowed to run in Europe. So I made it easy on myself and just run Trinity MHP 25% blend as does Byrons 2500.
I agree that most come shimed for 20 - 25%, but the 25% limit is an EFRA regulation. We can go higher in the Outlaw class. But is it worth it. 30% runs cooler so tyou lean it to get a steady idle and you chop the oil. Thus engines die quicker.
