clutch1

Out of curiosity, by how much do each of these increase cyl. pres.?

Water/Meth
Advance timing
Nitrous

JD730

I can't put a number on it, but advancing the timing too far all by itself is enough to kill a head gasket.

clutch1

I realize they all increase head psi. which one does the most.

Tiger Rag

As I understand it Water/Meth increases drive pressures more than nitrous. I read this in a post by Don M where he said he'd rather someone run nitrous and a lot of it rather than run water/meth. I think the reason was that the meth detonates in the cylinder - basically a fuel where nitrous does not detonate, it just cools the mix and allows for more efficient burning of your fuel mixture. Feel free to correct me if I am wrong, but this is how I understood it. I don't know how timing affects your drive pressures, I'd guess that it would, but that water/meth may contribute more to a failed head gasket than the other 2.

Tiger Rag

Here, I found it:

https://www.dieseltruckresource.com/...t=head+nitrous (it was a post about head studs)

Crank them down to 125 ft lbs. They are just fine at that level.

I know I am going to get reamed by some on this subject, but I have seen way too many gaskets fail with methanol systems installed. Water and a very small amount of meth might be ok, but many guys are blowing their gaskets on Diesel only. Some can be traced back to poor machine work, poor installation, and the inherent troubles with the 24 valve cylinder head VS the 12 valve design, but the methanol seems to be causing a detonation problem or a high peak pressure spike before or very near TDC.

The systems are just asking for long term reliability issues, IMO.

I would rather see you run Nitrous. Even lots of Nitrous. At least you dont get any detonation. No engine or gasketing system can take detonation for long. With a spark engine and meth/water you can get away with it. The cylinder temps are not high enough in most cases to pre-ignite the methanol. Unlike a Diesel that can have a 600 degree cylinder temp long before TDC.


Don~