LZ9 VVT / VCT, vs retrofit earlier "performance" cam. (Page 1/2) Raydar JUN 27, 07:28 PM I can almost see the eyes rolling, but in all my years, here, I have never seen anyone make this comparison. Assuming that I can use the stock PCM to accommodate the VVT*, or an earlier PCM since/if the VVT will no longer be an issue (I'm not afraid of either one.) ... Obviously (unless I've had my head in a dark place) there are no performance cams available for the VVT engines. There are plenty of performance cams available for the earlier engines. The retrofit to the LZ9 requires inserts to tighten up the cam clearance for the cam journals. Those inserts are also readily available. The one notable exception is the LNJ 3400 ('08 Equinox) that also uses a fixed, large journal cam. Obviously, it's not a performance piece. Guessing it can be reground, but it seems like a waste of effort. The question is, which method will provide the best performance, with a manual trans? I liked the way my Crane 272 sounded in my 3.4, and it pulled like a train on the top end, but I also have a VVT 3.5 in my G6, and GM did such a good job with it that it seems a shame to mess with the VVT, even if it doesn't have the slightly lumpy idle. I'm not averse to doing a bit of porting to the intakes, and changing throttle bodies. I don't really want to do a bunch of head work, though, other than really basic stuff. The engine will remain N/A. Will those mods help the performance of the VVT motor as much as they will the "fixed cam" motor option? Can the VVT cam use all that air flow? Thanks. *And yes I know that "VCT" is actually what's happening, but "VVT" gets used a lot more frequently. Raydar JUL 01, 05:00 PM <crickets> A_Lonely_Potato JUL 01, 09:31 PM way above my pay grade, sorry lol Raydar JUL 01, 10:11 PM Thank you sir! I just figured there was someone here who had built out an N/A LZ9, with deleted VVT, and maybe could give me an an idea what to expect. fieroguru JUL 02, 08:11 AM I would keep the VVT but it would take a fair amount of research work and tuning to maximize its performance. But once done, it would likely have a wider power band, better fuel economy, and fewer compromises than the single fixed cam setup. You could even make it chop at idle with some timing parameter changes in the tune. I would start with a custom cam with 10-15 degrees more duration and lift that allows use of peak head flow and then focus on the range limits and VVT adjustments to the cam to maximize idle, cruise, and WOT power up to 7000 rpm. If all you want is a peak power, then you can install a fixed camshaft designed to reach that goal, but idle, fuel economy, and low rpm torque/drivability will suffer. A_Lonely_Potato JUL 02, 01:13 PM quote Originally posted by Raydar: Thank you sir! I just figured there was someone here who had built out an N/A LZ9, with deleted VVT, and maybe could give me an an idea what to expect. i may be wrong, but it just doesn't seem to me like there are that many LZ9 builds. its the engine i'm wanting to do when i get around to swapping, and there doesn't seem to be all that much information specific to them on this forum. i would think it would be a popular swap, close to the same output as the 3800SC, but on reg gas and N/A. sure its got its techy stuff like the VVT and variable intake, but those can be deleted without *too* much work. everything i've seen suggests its a pretty strong engine. there was a guy(slowv8fiero) who boosted his to 600hp on stock bottom end, so i would think ~350hp would be pretty achievable. Raydar JUL 02, 04:17 PM Thanks again, gentlemen. quote Originally posted by A_Lonely_Potato: i may be wrong, but it just doesn't seem to me like there are that many LZ9 builds. its the engine i'm wanting to do when i get around to swapping, and there doesn't seem to be all that much information specific to them on this forum. i would think it would be a popular swap, close to the same output as the 3800SC, but on reg gas and N/A. sure its got its techy stuff like the VVT and variable intake, but those can be deleted without *too* much work. everything i've seen suggests its a pretty strong engine. there was a guy(slowv8fiero) who boosted his to 600hp on stock bottom end, so i would think ~350hp would be pretty achievable. 600 HP on a stock bottom end. Maybe. He's done some nice stuff, and knows his way around most any 60 degree V6. Doesn't mind breaking stuff to find out what works. Although he makes that 600 claim, I've yet to see a dyno sheet. Although, to be fair, I haven't looked really hard. (He's the one that used to troll V8 owners about posting a dyno sheet or time slip. Yeah... that guy. Irony. ) pmbrunelle JUL 02, 06:14 PM quote Originally posted by Raydar: 600 HP on a stock bottom end. Maybe. He's done some nice stuff, and knows his way around most any 60 degree V6. Doesn't mind breaking stuff to find out what works. Although he makes that 600 claim, I've yet to see a dyno sheet. Although, to be fair, I haven't looked really hard. (He's the one that used to troll V8 owners about posting a dyno sheet or time slip. Yeah... that guy. Irony. ) 522 whp on dynojet with graph: https://www.realfierotech.c...iewtopic.php?t=21900 I think that 600 hp is what Shaun estimates at the flywheel based on the wheel horsepower measurement. That's with a junkyard LZ9 engine and LNJ camshaft. A_Lonely_Potato JUL 02, 10:50 PM quote Originally posted by pmbrunelle: I think that 600 hp is what Shaun estimates at the flywheel based on the wheel horsepower measurement. yeah i knew it wasn't that exact, and i did forget to mention it was his claim to be a stock bottom end. he did wind up blowing it up im pretty sure though haha Raydar JUL 03, 10:09 AM quote Originally posted by pmbrunelle: 522 whp on dynojet with graph: https://www.realfierotech.c...iewtopic.php?t=21900 I think that 600 hp is what Shaun estimates at the flywheel based on the wheel horsepower measurement. That's with a junkyard LZ9 engine and LNJ camshaft. Well... okay. Fair enough. I stand corrected. Thanks! I never saw that. I guess I figured that if they weren't posted on one of his YouTube vids, they didn't exist. But he's running a stock cam, since he's boosted to a fare-thee-well. I'm not interested in boosting. At least not at this point. But at least it proves the sturdiness of the LZ9 bottom end.