HOSS99

I'm purchasing some Absolute 5.3stgII's Heads. My current CAM is the MTI B1
221/221 .559/.559 114 +4. So far I've gotten 2 recommendations for a new CAM to use with these heads, and have similiar idle, but make more power than the B1.
Absolute recommended - 230/230 .591/.591 114 +4 XER
APE recommended - 228/232 .600/.600 114 +4

I was curious (and of course I'll ask Absolute and APE before I decide), what would just adding the SLP 1.85 rockers do for HP/Trq, and how would it change the powerband?

B1 specs w/ 1.85 rockers would be - 221/221 .608/.608 114 +4?

Has anyone ever tried small duration with high lift?

I was thinking about ditching the the stock rockers anyways so this could save some $$.

Harland sharp also offers 1.8 ratio rockers.

With HS1.8 rockers B1 specs are - 221/221 .592/.592.
That might work!! hmm....

What do you all think?

Thanks,
Bryan

jrp

iTrader: (16)

i'd just go with the bigger cam, will be cheaper then the rockers anyway. i'd get a new cam and some HS 1.7 rockers. I have a T1 and have been told not to use higher ratio rockers.

with the rockers your looking at about 1-2* more duration as well as the higher lift.

HOSS99

It will increase duration too, I didn't know that.

HOSS99

From the amount of responses, I guess this is not a very popular idea.

chino_man279

iTrader: (7)

With the aggressive ramp rate of the cam, I would not go with a higher ratio rocker arm. It will be extremely hard on the valve springs. Just get the bigger cam and do the simple swap for the power. When you sell your current cam you can buy the 1.7 HS rockers, so all you are out is the cost of the new cam. Pretty cheap for a modest power gain if you ask me.

Conv.WS6

Hello All, I'm new to this forum, but I've been around for a while in the ls1 forum. I don't quite follow how rockers on a medium lift cam are harder on the valves than a higher lift cam with stock rockers. If they both come the same result duration and lift on the valves, how could it be any harder on the seats, springs, and valves? Maybe I'm missing something, and someone can educate me a bit.

98SS Blackattack

The overall lift might be the same but the smaller cam has fast ramp rates[sharper lobes] which in turn is harder on springs

Conv.WS6

ok just for fun lets do this:
224/224 .550 .550 mild cam
with 1.85 rockers
will be aprox.
225/225 .600 .600

in comparison to a good size cam
225/225 .600 .600
with stock rockers.

It's all about the end result through duration and lift instead of the general statement of roller rockers being hard on your valvetrain correct?

I understand that a 209/209 .600 .600 cam or cam+rockers is going to be harder on your valve train than a longer duration, but I'm concerned with the rockers only.