pillagenburn

iTrader: (2)

I haven't seen anything to indicate that you can't do that.

gofastwclass

iTrader: (2)

Why would you? Doesn't it deactivate when you get on it hard? I thought it was supposed to determine by load if it needed to be enabled. Not sure though.

My next question - does DOD actually make a real world fuel mileage difference? I've only seen it in heavy trucks but never driven or know anyone who owns one. VVT seems the way to go once the tuning research has been done.

KurtRardin

iTrader: (11)

I read an article where they were having trouble getting their turbo G8 to cooperate with the DOD (because it kept kicking in or something). I was thinking more along the lines of keeping it from cutting on unless you wanted it to cut on.

Are the stock L92/LY6 DOD lifters going to hinder any aspect of performance (ie are they freakin heavy, or unstable on the high side, or something)?

Jimbo1367

LY6s don't have DOD, I don't beleieve L92s either. Just vwhat I've heard/READ

bonecrrusher

iTrader: (1)

AFM or DOD is not the same as VVT....

KurtRardin

iTrader: (11)

I know the L76 has AFM, but I see guys with Caddy L92's talking about AFM on the message boards all the time. I wonder what engines come with it and which don't... obviously LS1/2/3/4/6/7/9/A do not.

kballs

iTrader: (1)

That link that was posted of the GMHTP cam sawp article said it used a factory ecm, but didn't say who's product it was to make it a stand alone deal.

pillagenburn

iTrader: (2)

AFM/DoD lifters are, from everything I've heard, pretty much undesirable from a high performance aspect. If you simply want the fuel economy aspect of AFM and with a lot of performance but don't plan on modding past bolt-ons then by all means keep the AFM.

I can see wanting AFM in a F-body.... I can't even imagine the gas mileage you'd get.

gofastwclass

iTrader: (2)

What kind of economy gain are we talking about?

pillagenburn

iTrader: (2)

well, 1500 series trucks with 5.3L AFM motors are getting in the low-mid 20's from what I've heard. So I imagine mid 30's on the highway with a 6-speed keeping the revs low? Just a guess.

KurtRardin

iTrader: (11)

I'd say mid 30's on the road as long as you kept it under about 70mph. With HPTuners open showing a MPG PID I noticed that 70mph was about the cutoff for any kind of decent fuel economy, with either 3.42 or 4.10 gears. Once I achieved 34mpg on the highway, but that was following semi's at a "mythbusters" distance, and pushing it into neutral on the downhills. If I could have cut the engine in half then I could only imagine how good the economy would have been.

I've been trying to figure out what a functioning VVT engine would sound like with a MAST cam in it. I can only guess that when you allow for camshaft advance/retard on-the-fly then most of the traditional cam geometry theories would change. Would there be as much overlap? Would LSA still function the same (shifting the power band up or down the RPM range)? What would a cam with decent duration sound like at idle? I do know that lift becomes an issue unless you change to some pistions with valve reliefs.

The badass thing about building an L92 to utilize VVT (or to hack it up and have a backdoor LS3) is that you get L92 heads for free.

I wish I could get MAST to come comment in here. I'd love to know if it's even possible to rock an aftermarket cam and keep AFM.

Jimbo1367

I think you guys are guessing alittle high. I had a 07 Monte SS and going 67-68 MPH on a trip I routinely got 26-26.1 MPG. So unless you held your speed to a max. of 55 MPH, I doubt you'd get over 30 MPG

pillagenburn

iTrader: (2)

I think people forget that comp makes vvt cams too.... lol.

68Problemchild

iTrader: (1)

Just a comment on the speedo. There is a kit to keep the original old style 68non electornic speedo via a tranny add on for the 4l60E. I have not tried it but a local tranny guy uses it and gave me the link.

http://www.jagsthatrun.com/4L60_Order.html

I will be running as many of the original gauges as possible in parallel with the L92.

mr220v

We could use a signal adapter of some kind, but we're looking to get the cleanest/cheapest solution possible. No adapter=cheaper and less wiring.

KurtRardin

iTrader: (11)

I dunno, I can routinely get about 28mpg on a non-stop road trip with 4.10 gears and a M6, as long as I keep it under 70mph. If AFM could account for, say, a 15% increase in highway fuel economy the that would put me at about 32+mpg. I guess the real test is to actually find an fbody with a fully functioning AFM engine. Fuel economy would be one of my goals, I think.

cam

iTrader: (9)

Pillagenburn I'm guessing you used the stock LY6 injectors correct? Any issues with fitment to the L76 intake? Fuel rail?

Thinking of DOD does anyone have any idea if the DOD injectors are visibly different? I'm just looking for tips on how to identify using the "old school" eyeball methods whether its a DOD LY6 or not after its been pulled without having to run numbers.

pillagenburn

iTrader: (2)

I used LS2 injectors that I got in a rail/injector kit. Was only like $100 or so, so I figured I might as well. They work great, no real fitment issues.

cam

iTrader: (9)

I see. Whats wrong with using the LY6 injectors? Do they not mount onto the LS2 rail? Or is it electrical differences?

chevellepowered

iTrader: (37)

i tried putting them in the ls3 intake and there way loose.. think you would need the oring kit.. but im just going with 60lbs injectors anyway.. if i can afford them..