Vishnu/cam timing, splitting hairs
Vishnu/cam timing, splitting hairs
Vishnu,
I'm probably splitting hairs here, but I have basically your stage 1 (v360) package, plus lower IC pipe... In regards to cam timing, your website states -5/-5 will help with top end and resistance to detonation.
My question is..... is that on low octane Cali. juice, or is it for all fuel grades? The reason I ask, I'm in Texas and run only 93 octane. Are you gaining the top end because the ECU isn't pulling out timing due to detonation on crappy fuel, or because the car basically likes the retarded cam settings? At -5/-5, I've got a flat spot from peak torque until about 5800 rpm, at which point the car starts to pull harder till redline. I'd like to get rid of the flat spot by setting cam timing closer to stock, but not at the sacrifice of that last 1000 rpm of increased power. With the higher octane fuel available in Texas, will I still resist detonation on the top end, and allow me to increase midrange by moving the cam timing closer to stock?
My butt dyno doesn't seem to have the calibration records or sensitivity of a lot of posters here, so I haven't tried different settings to gauge the real world impact. Just looking for the hypothetical response (or the dyno proven response) prior to spending a weekend filing down my butt cheeks, trying to find the raw nerve endings that will allow me to gauge the 5-10 hp impact of various settings.
I'm probably splitting hairs here, but I have basically your stage 1 (v360) package, plus lower IC pipe... In regards to cam timing, your website states -5/-5 will help with top end and resistance to detonation.
My question is..... is that on low octane Cali. juice, or is it for all fuel grades? The reason I ask, I'm in Texas and run only 93 octane. Are you gaining the top end because the ECU isn't pulling out timing due to detonation on crappy fuel, or because the car basically likes the retarded cam settings? At -5/-5, I've got a flat spot from peak torque until about 5800 rpm, at which point the car starts to pull harder till redline. I'd like to get rid of the flat spot by setting cam timing closer to stock, but not at the sacrifice of that last 1000 rpm of increased power. With the higher octane fuel available in Texas, will I still resist detonation on the top end, and allow me to increase midrange by moving the cam timing closer to stock?
My butt dyno doesn't seem to have the calibration records or sensitivity of a lot of posters here, so I haven't tried different settings to gauge the real world impact. Just looking for the hypothetical response (or the dyno proven response) prior to spending a weekend filing down my butt cheeks, trying to find the raw nerve endings that will allow me to gauge the 5-10 hp impact of various settings.
forgot to add.... that's without the x-flash tune. I'm signed up for the tuning session you plan on having in Texas (Dallas) in November. Since this will be my first x-flash, do you plan on bringing some boost emulators with you, or should I pre-order this and have it already installed prior to the weekend?
thanks for the guidance! If I don't hear back from you within 23.4 minutes, I'll get pissed, and call it bad customer support!
thanks for the guidance! If I don't hear back from you within 23.4 minutes, I'll get pissed, and call it bad customer support!
Evolving Member
Joined: Feb 2004
Posts: 464
Likes: 0
From: Livermore, Ca
Ok, get pissed and go fight the world..with a sword. 
Generally..well it was not my intention to state the obvious, but, once you get the xflash/tune it will take care of any minute discrepancies your vehicle may have. -5 on both ends has been the 'default' setting with Vishnu cg's, and the preferred one at that for stage 1 cars all around the US regardless of the octane available to them. This is me quoting myself ---> "Correct me if I'm wrong(dustin...shiv) but, generally adjustable cam gears are going to allow you to throw more timing in areas you may not have been able to safely do so before, thus boosting the power output. " I'm not really sure if I thoroughly answered your question if at all, but hey, its 1am, and I just worked 16 hours. Oh and yes Shiv brings a plethora of emulators with him to dyno days. 
Generally..well it was not my intention to state the obvious, but, once you get the xflash/tune it will take care of any minute discrepancies your vehicle may have. -5 on both ends has been the 'default' setting with Vishnu cg's, and the preferred one at that for stage 1 cars all around the US regardless of the octane available to them. This is me quoting myself ---> "Correct me if I'm wrong(dustin...shiv) but, generally adjustable cam gears are going to allow you to throw more timing in areas you may not have been able to safely do so before, thus boosting the power output. " I'm not really sure if I thoroughly answered your question if at all, but hey, its 1am, and I just worked 16 hours. Oh and yes Shiv brings a plethora of emulators with him to dyno days.
Last edited by lambtron; Oct 12, 2005 at 09:34 AM.
The -5/-5 setting reflects an attempt to get the most hp from the smallish factory cams, which comes at the expense of low speed torque. This cam timing setting is very forgiving with respect to detonation because it doesn't do anything to enhance power in rpm ranges most prone to detonation.
The relatively short duration of the factory cams is such that you will not be able to get much of something without giving up much of something else. If you want to get serious about performance, consider a cam upgrade, such as the HKS 272 set, used with more conventional timing. It's a very worthwhile effort.
The relatively short duration of the factory cams is such that you will not be able to get much of something without giving up much of something else. If you want to get serious about performance, consider a cam upgrade, such as the HKS 272 set, used with more conventional timing. It's a very worthwhile effort.