I ride at 8 to 10000 ft elevation I was wondering if and how much you can cut on an 03 mtn viper heads to get back some of that lost compresion at high altitude. thanks.
PowerValve-700
New member
I don't know much about this topic but I do know most people just remove 1 or 2 layers from the head gasket. If you really want to cut the head just measure the thickness of 1 or 2 head gasket layers and there you go.
Viper's center layer is .005" thick. The outer layers are .010" thick. Pulling just the center layer will reduce total combustion chamber size by .475 cc. Pulling the center and bottom layer will reduce total camber volume 1.42 cc.
I ran mine with 2 layers pulled, with the stock pipe at 2000' to 7000' no problem. Just be sure and use good fuel.
With 2 layers pulled the squish on the center and mag cylinders is .055" on my sled. I dont think I would want to run it any tighter then that, on pump gas.
I ran mine with 2 layers pulled, with the stock pipe at 2000' to 7000' no problem. Just be sure and use good fuel.
With 2 layers pulled the squish on the center and mag cylinders is .055" on my sled. I dont think I would want to run it any tighter then that, on pump gas.
dmaxx
Member
Mt.Viper:
I am considering using the Bender opticool gasket and removing the center layer. I was told not to use this on a single pipe sled. Any opinion on this? How much do you think I could expect from this mod running at 1000 ft or less? Thanks.
I am considering using the Bender opticool gasket and removing the center layer. I was told not to use this on a single pipe sled. Any opinion on this? How much do you think I could expect from this mod running at 1000 ft or less? Thanks.
The Snakester
New member
If you look at you head you will see that there is one side that has a larger chamber than the rest. If you want some professional advice call Bender Racing I was going to do the same theing and they did not recomend it.
dmaxx, I dont have any experience with Bender's gasket. Not sure if they are the same thickness,etc. So I cant give you a good answer on that one.
I have run my Viper with both one and two layers removed with the stock pipe, with no problems. I should point out that I do ride at higher elevations and that does make a difference.
One layer removed (center)should be no problem for your altitude with good premium fuel. The important thing to remmember when doing compression mods is to make sure your jetting is correct and dont be cheap when it comes time to by fuel! While .005" is not a huge HP gain, throttle response is improved.
I have run my Viper with both one and two layers removed with the stock pipe, with no problems. I should point out that I do ride at higher elevations and that does make a difference.
One layer removed (center)should be no problem for your altitude with good premium fuel. The important thing to remmember when doing compression mods is to make sure your jetting is correct and dont be cheap when it comes time to by fuel! While .005" is not a huge HP gain, throttle response is improved.