just curoius what every one thinks the most power N/A the 3.5 and 3.9 could do with things like direct injection, 3v, "performance breathing"? mine- 3.5L - 270hp 250lbft 3.9L - 310hp 270lbft

Well it could always be cammed, port/polished, etc...

I think there was a story from sema a couple years ago the the 3 valve 3.9 would be around 270 hp.

I think those numbers may be a bit high for "from the factory" Loki. I think 260hp 260lbft and 290hp 280lbft are a bit more likely.

My belief is that GM could easily get more power out of their engines but dont because the mileage suffers and you cant beat the CAFE regulations and win sales if your not competitive in mileage, its more important than 10 -15 hp in the eyes of the average customer. So I believe they have kept them somewhat "choked" down. This has been my experience with the 38 anyhow. origionally they had something like .37 or .42 total valve lift, Im sure this improved as they got the engines worked out so the power was up and the mileage good. This is going to be the challenge for the 3.9, to get the power and improve the milage. It seems to me back when i did some power estimates on the V6's as if they performed equal per displacement to the LS1 or 2 ( I now forget which one of them I used) they would be around 260 on the 3.8 so just a tad more for the extra 100cc on the 3.9. If you wanted 280 or 300 you would be looking at serious performance mods like high compression and cam duration that would destroy the gas milage and require the expensive gas.......all sales NO NO's. Hopefully we will be seeing a supercharged 3.9......now that could easily reach 300 and maintain equal mileage under normal driving conditions.

i did push the numbers up just alittle , see what reactions it would cause. not tring to be an @ss about it though

with direct injection i believe those numbers are very plausible

GM did show-off a 270hp 3-valve 3.9l at Sema (2003 I believe). Direct injection would add (guessing here) another 5-10%? That would put it in the neighborhood of 285-300hp.

i did push the numbers up just alittle , see what reactions it would cause. not tring to be an @ss about it though

[post="65465"]<{POST_SNAPBACK}>[/post]

since you didnt stipulate this power level being from the factory, i think your numbers are a bit low.