Torquemonster
Enthusiast
There has been some excellent dialogue on the "How Much Timing Can A NA Viper Take?" where an issue surfaced surrounding problems some people are having with VEC2 equipped Vipers.
This is not a criticism or necessarily even a fault with the VEC2 itself - but a problem that some cars are experiencing that nobody seems to have solved yet.
It seems to me that the issue is common enough to justify a think tank on a seperate thread because the solution once found is going to benefit everyone with the problem and it is something I know all tuners and DIY guys will want to be up to speed on incase they ever encounter it.
Sean Roe made an excellent post about this on the other thread and has promised to modify the VEC2 if that proves to be the source of the issue - OR - to update the trouble shooting manual and instructions if there is something that needs to be done outside the VEC2 when installing it that will eliminate this problem. I applaud this and we need to support him by doing what we can to solve this mystery.
In a nut shell - what happens is that when certain cars affected hit an rpm level - which is different on different cars - it can be 3200rpm, 4500rpm or even up to 5200rpm.... the engine will hit a flat spot and drop power like it does not want to rpm more, or does but sounds terrible. Almost like it drops a cylinder.
There have been some suggestions that dropping timing out at the rpm range affected helps - it will be interesting to see if some have had this problem running factory timing tables or pulling timing OUT eg. on boosted applications.
Let's use this thread to share the nature of the problem, suggestions on what it may be and how to fix it - and experiences that have solved it for you. Together a solution will be found and this is a great use of the forum because the VEC2 is an important asset in this community.
BTW - somebody asked so here is the answer - AEM does not have this problem (to the best of my knowledge so far) - but AEM is not for the novice either and it costs a LOT more than a VEC2. I support both AEM and the VEC2 because they both fill different needs and market segments - we really need them both.
This is not a criticism or necessarily even a fault with the VEC2 itself - but a problem that some cars are experiencing that nobody seems to have solved yet.
It seems to me that the issue is common enough to justify a think tank on a seperate thread because the solution once found is going to benefit everyone with the problem and it is something I know all tuners and DIY guys will want to be up to speed on incase they ever encounter it.
Sean Roe made an excellent post about this on the other thread and has promised to modify the VEC2 if that proves to be the source of the issue - OR - to update the trouble shooting manual and instructions if there is something that needs to be done outside the VEC2 when installing it that will eliminate this problem. I applaud this and we need to support him by doing what we can to solve this mystery.
In a nut shell - what happens is that when certain cars affected hit an rpm level - which is different on different cars - it can be 3200rpm, 4500rpm or even up to 5200rpm.... the engine will hit a flat spot and drop power like it does not want to rpm more, or does but sounds terrible. Almost like it drops a cylinder.
There have been some suggestions that dropping timing out at the rpm range affected helps - it will be interesting to see if some have had this problem running factory timing tables or pulling timing OUT eg. on boosted applications.
Let's use this thread to share the nature of the problem, suggestions on what it may be and how to fix it - and experiences that have solved it for you. Together a solution will be found and this is a great use of the forum because the VEC2 is an important asset in this community.
BTW - somebody asked so here is the answer - AEM does not have this problem (to the best of my knowledge so far) - but AEM is not for the novice either and it costs a LOT more than a VEC2. I support both AEM and the VEC2 because they both fill different needs and market segments - we really need them both.
