245 bhp on a 3.1/3400/3500 hybrid-possible?

[AaronGTR]

With no cam and no increase in compression.... no way you are going to break 240chp. That's my opinion.

[Superdave]

With no cam and no increase in compression.... no way you are going to break 240chp. That's my opinion.

not an opinion.. that's a fact.


(Unless boost or nitrous is involved)

[no_doz]

no new thread right now, i have all my questions answered-after looking into building the gen 2 engines for a long time, & looking into building 3100/3400's, ive determined that with 3500's available for $300-500, with gas mileage, convenience, & power goals in mind, anything but a 3500 is a waste for me to even consider dicking with.

its just too bad it took me so damn long to come around, what can i say-i wouldve never dreamed stock LX9's are rated for better mpg than the 3100 models (& my old 3100 got 29-30mpg pretty commonly).

also superdave-i assume you are the one on youtube with the "3500z"? if so can you post some take off vids from outside the car? that thing is a BEAST & also how is your mpg if/when you drive it nicely (IF lol)?

[asylummotorsports]

My 3500 with headers, TB, and a really good tune has been guesstimated at 235 based on my ET and MPH.

That is a 17% increase on the stock number so not so bad I suppose, but once you do the basic stuff, the last 10 or so will mean getting more involved.

Ben claims I may get another 30-40 HP with the cam selection he provided, but I have to admit that is likely a little optimistic. (But it won't stop me from doing it!! LOL!)

BTW I can average 25 mpg even with my 3.73 FDR and no TCC.

[IsaacHayes]

Eric, your TB doesn't really count as a mod in my book, since the 3500 came with a 65mm stock to begin with... So the only real mod to the 3500 is headers........

[Superdave]

I get 10-12 in the city and 30-35 on the highway as long as i stay out of PE mode.


"once the pedal hits the floor gas mileage is out the door"


the only other vids i have are of track runs, there are a few on Streetfire.net.. search for 3500z.

[robertisaar]

I get 10-12 in the city and 30-35 on the highway

that is QUITE a spread... the MC is around 20 in the city and 30+ highway...

[Superdave]

yah, my AE is a little off...

every time i shift the AFR's drop from 15's to 12's.. lol

[robertisaar]

15 to 12 is 25%....

but at least it shouldn't surge...

[no_doz]

AE? also what cam profile are you working with?

[robertisaar]

AE meaning Accel Enrich.... if you're used to a carb, it's analogous to a pump shot. it adds extra fuel in due to the column of air that's sitting right before the throttle body.

think of it this way: when you make a rapid throttle transition, the air before the throttle body, but after the air filter, gets "torn" and actually has a SMALL supercharging effect that lasts for about 12.5-25 mSec, though a lot of factors play into it, depending on engine size and speed, air filter size, volumetric efficiency, intake design, etc, etc....

if it's lean, it's like driving a car with a vacuum leak, when you go from a light, it feels like it dies for a fraction of a second, then kicks back up. rich kills your economy a little bit, and if it's REALLY rich, it will make a slight bog, but nowhere near as bad as going lean. with enough time and tunes, you can make it perfect.