moregrip

iTrader: (8)

how many " of vacuum were you pulling at idle in gear and out for both cams?

zippy

I can fully understand the issue. The same vehicle i found the injector size problem on (04' SS), we also installed a cam in. The first set of injectors installed were 57lbr's and there was no way to get that to idle anywhere respectable when it was cold and it was damn fussy warm. The next change was to SVO 42's which were 49lb hr. at the pressure the 04' fuel system runs at. This allowed for a better idle, but with the drag caused by the 2.8 pulley and a/c when it was on was one fussy pain in the *** until it got about 500 miles on a tune. It would constantly want to stall cold when turning the wheel and occasionally warm. The cam we put in that was 220/224 .570/.577 with 114+4. Fortunatly not having electric fans helped, but after putting about 80 flashes in the truck with about 60 of them being changes in the idle I can certainly understand your frustration. I remember thinking when i finally got somewhere with the truck that any more cam, injector size, or load and the truck would just be work to drive. In order to get things smooth with no loading up in slow speed driving i had to run the idle at 890 in drive with the a/c on.

jombob, that is quite a list of tuners you have there.

BigBlackAv

I have this issue as well...would it help to get some of the accessories off of the vacuum system...ie brakes...there is a company that makes a hydrolic assist system that would disconnect the vacuum from the brakes and make it more available for other things...am I thinking straight? would that work...anyway the company that makes it doesn't yet for our model trucks, but, maybe soon.

zippy

running your brakes on a hydro assist just puts more work on the power steering pump. not likely going to be much help.

BlownChevy

iTrader: (20)

So let me get this straight....Am I to understand that it is not a cam problem, it is an injector problem? Or is it just a combo of the two??

jimbob

iTrader: (2)

I think a combo of all 3 maybe...fly-by-wire tables (or lack of them), injectors and cam...Sounds like it just wasn't going to play...Hey Brian...we likey your cammy...Funny thing is it feels just as strong...Butt-O-meter bad on something this big though! Drag strip will tell the tail, the weather hasn't changed much up here so we should be close to conditions of a few weeks back....

Yeah, I didn't even mention about all the local car tuner guys up here that in on our race team that we posed the question too. I believe at one time I asked Cory if he would ask you about any thing we might be over looking...but I think that got lost on tune 100 hehehehe.....

Holy **** batman that is alot of rpm for auto...must have a stall? Yeah we tried 850 one time but the load on the verter just made it worse, hmmm maybe a big stall might have helped some...

jimbob

BlownChevy

iTrader: (20)

I have been talkin about that cam for a LONG time........Mr. Lingenfelter knew what he was doing with these LSx motors.

zippy

i'd have to agree that with the throttle blade doing all the idle controls that this is the main problem. i never run into this much work tuning something that runs an iac system. i have fortunatly had some experience in working with a radix truck with the same cam you chose to replace it with. i'd say your 60' will get a bit better if you can get traction under control, but you may lose a bit in the mph. i'd guess about 1.5mph loss and around .2 seconds in E/T. considering how much better that LPE cam is at idle it'll be well worth it. they idle almost smoother than stock. tuning that is a walk in the park.

jimbob

iTrader: (2)

Yeah, I know...I've been working on hotrods sense I was 8. I wish I would of had just a little of his mojo....To bad he's gone, we really lost a knowledge base there....I'm sure he's hotrodding somewhere else now....

Zippy After the CheaTer cam install and tune...We only gained 2 miles an hour and 2 tenths, but on this heavy rig that's probably 40 engine horse. Maybe with alittle more AFR tweaking we might be able to coax just a little more out of this cam...Like tghe same mile an hour would be nice....

cheaTer....out of gear was 15 inches maybe 15.5 if very warm, In gear was 14 inches as long as you did not hit the breaks or turn wheel or have climate control/electric fans come on....then all hell would break loose.

LPE...out of gear was 18 1/4. In gear is 17.5 I believe, only glanced at the gage a few times.


Jimbob

zippy

sounds as if you really had that tuned well then with the stock cam. i was expecting that you'd gained more with the big cam. in that case i'd think the LPE cam should gain you the same amount.