Elcaballoloco

iTrader: (3)

I'm new to the LS1 world (well engine world in general), and as I sit here and do my research for the right cam, I have come across one question that stumps me. im seeing on some cams they are recommending to not use a 1.8 rocker with them due to the ramp rate. why is this? what would be the consequences?
my theory, and please correct me if im wrong, is that im trying to look for just the right cam to get good low rpm power without sacrificing alot up top, so what im doing is see all these cams that will do that for me, such as the tr224/224, but they recommend to not use a 1.8 rocker because of the ramp rate. i wanted to find a good cam that i could put a 1.8 on and bring the lift up to that of a ms4, trex, or others along those lines, if need be. i dont want to outright buy such a large bumpstick, but all those that im saying that i could up the lift to the status of one of these larger cams is pretty much saying dont do that.
can anyone please explain?

98 t/a m6...bbk intake, throttle body, maf, hooker lts, looking to go 4.10s or 4.30s if i choose to keep it on the track with a bigger cam
fixing to do head/cam/timing chain/oil pump all at once but can't figure this cam thing out

Greg Good

On aggressive lobes a 1.8 rocker would give the valve too much velocity, causing it to float. If a cam grinder tells you not to use a 1.8 rocker with a certain lobe it's becasue they've already done it and it didn't work out.

Hydraulic roller cams can be very aggressive. I've seen a good many on a cam doctor that had acceleration rates as high as a solid roller. The problerm is that you can't run as much spring on a hydraulic roller. Some guys are backing off the ramp speed and going for smoother lobes that turn more rpm. They make up for the loss of "area under the curve" by getting the heads maxed out.

HTH

vettenuts

iTrader: (4)

The Vinci line of cams are designed for use with 1.8's, have you looked at them?

>>>>>>>>>>>>>>>>>>>>

Elcaballoloco

iTrader: (3)

nope, but i'm getting ready to now!
so my idea of running a smaller lift and if im not pleased with it and going to 1.8s to get more lift is sort of bad idea?
i have a feeling its not that easy...

teke184

iTrader: (5)

lsx heads have fantastic flow at high lift....why not just save the time, trouble and most of all MONEY...and buy a cam with high lift designed in.

any of the cams from .590-.610" lift will run great...no need for $500 high lift rockers.

brad8266

iTrader: (23)

1,8RR's arent gonna make a difference anyway, just stick with a good set of 1.7's since thats what most cams are designed around.

mrr23

iTrader: (3)

i beg to differ on that. the right set of rocker WILL make a difference.

vinci/crane 1.8 accelerated lift rockers in stock cam in the wife's car

brad8266

iTrader: (23)

My bad I meant to say not much of a difference, especially on a cammed car. In a stock cam car yeah it is a decent mod, but not in a cammed car. Just my opinion.

hammertime

iTrader: (1)

How much lift do you need for that duration? All the following lobes are Comps:
If you are switching cams, seems like you may as well get the lift you want from the lobes.

mrr23

iTrader: (3)

cammed or not, you'll get, at least, the same results.

quick346

iTrader: (4)

I will let you know .I am putting in the tr224 this week with the comp 1.75 pro mags.

Only because i don't feel like takeing a loss on them i already had them before the cam.But i had been running them on a comp xr281. but this will be a faster lift rate.

comp 228/230 @.050 .581/.587 with 1.75
TR224 114 224/224 .581/.581 with 1.75 rockers

Less duration and more lift but with the AFR duals i can't see it being a prob. I will know by sunday.