Getting ready to tune an LT1 (stock cam) with a Vortech on it. When you guys run boost on a stock motor do you generally zero out the timing? Leave some retard or run full?
Getting ready to tune an LT1 (stock cam) with a Vortech on it. When you guys run boost on a stock motor do you generally zero out the timing? Leave some retard or run full?
Depends on how thorough you want to be, how much time you want to spend on the tune for it to be right, how much power you want to make and how happy you want the customer to be. There are some on here that just 0 them out and then the customer gets iffed - I know cause they usually email me or talk to one of my other customers griping and then I hear it from that person... I personally don't 0 them out. There's a lot of fuel economy and power up top with variable cam timing - whole reason they came out with it. Downside - to do it right and have a vehicle that drives and operates right - you have to dial in individual torque models / lock the cam at 0 and dial in VVE / unlock the cam and dial in your multipliers to keep fueling and torque calcs right for variable cam timing / usually dial A LOT of other things in that don't usually get touched in the calibration.
So all in all - it's up to you and what your customer wants. I will say with a blower it's noticeable up top when you get the timing dialed in with AM cams - you can usually leave NA cams setup to or right around where they already are, so the numbers are basically already there for you. Up to you....
2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80
~Greg Huggins~
Remote Tuning Available at gh[email protected]
Mobile Tuning Available for North Georgia and WNC
I change the VPC Spark Table a little bit depending on how I change the High Spark table, usually reducing it but I also reduce the VVT movement. I've found that copying the Low Baro VVT table to the middle and high tables is a good starting point. This alone will reduce the VPC spark even if you leave that table stock. In my opinion, if you are going to let the cam move then you should leave the VPC spark table functional even if you edit the values.
Are you guys talking about cruising or wot?
Both. Mid throttle mpg and torque improvements with variable cam timing / Drivability better / WOT power WAY better. I've basically got two different wot tables I use for testing when dialing them in remotely to see which way the cam does better - more raspy usually does better more retarded even with boost. 0ed out is almost always worse - big time noticeably worse, but WAY easier to tune...
2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80
~Greg Huggins~
Remote Tuning Available at gh[email protected]
Mobile Tuning Available for North Georgia and WNC
I figure they have advance built into the the cam for the mid range and low end. So retarding up top is a must. Once I get the fuel system straight I'm going to mess with it a bit.
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