Ls3 418 hates the street Help
#62
Super Hulk Smash
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I drive mine at 1400 RPM... So I would say that's pretty stock. The thing that's more annoying about my car is the 3000 RPM to get moving in traffic due to the stall... which with my exhaust is insane. But the cam itself doesn't buck. And it only very rarely hitches on decel below 2000, but that's more of an issue with my injector wall fueling not being optimized, and I haven't got around to messing with it. But I end up going rich for a moment when I take my foot off which causes the hitch.
And cubic inches do make a difference. Read the vacuum of the same cam in a 346 then put it in a 418. You'll gain like 3-4" of vacuum. That means you can use a commensurately larger cam to end up with the same vacuum as the original cam in the 346. It just so happens that around 8 degrees is what it typically takes per 50 cid to equalize the vacuum reading.
As others have said. If your cam isn't doing what you want it to do, your tune is off.
And if you have a Gen IV PCM, there's no reason it can't compensate. I'm working with a slow *** Gen III PCM with an IAC...
And cubic inches do make a difference. Read the vacuum of the same cam in a 346 then put it in a 418. You'll gain like 3-4" of vacuum. That means you can use a commensurately larger cam to end up with the same vacuum as the original cam in the 346. It just so happens that around 8 degrees is what it typically takes per 50 cid to equalize the vacuum reading.
As others have said. If your cam isn't doing what you want it to do, your tune is off.
And if you have a Gen IV PCM, there's no reason it can't compensate. I'm working with a slow *** Gen III PCM with an IAC...
#63
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My 257/272 drove like stock out of Vengeance, as did the 251/259 that was in before it. Good tune+huge converter takes all the bad manners out of driving around town, and the thing would cruise in lockup at 1400rpms, can't really ask for more then that. The modern PCMs are WAY better then gen3 stuff.
#64
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Wow, so its not 100% exactly just like stock, but pretty f'in close. No one said anything about a "super tuner", however Clint at AIR in Denver tunes my car. The car had a awesome tune for the size cubes and cam. Could drive the car anywhere with no issues. No bucking at low RPM's once he finished dialing the tune in. Never really drive the car under 1400 rpm. When on the highway I drive it about 1600-2000 rpm in 6th gear about 75-80mph do to my steep gear in the rear.
Recently I switched intake manifold to the Holley Hi-Rise, new intake setup and larger injectors for e85. So I can keep you all posted if you like on how my tune is working out with the recent changes.
Recently I switched intake manifold to the Holley Hi-Rise, new intake setup and larger injectors for e85. So I can keep you all posted if you like on how my tune is working out with the recent changes.
#65
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When VE and MAF tables are correct then PE should bs set to the correct fueling (about 12.5-13.0 for NA).
With the E38 it's difficult to hit the airflow limit, so P1514 indicates you have to edit the airflow/throttle sanity table(s).
Last edited by joecar; 12-12-2015 at 05:29 AM.