1.5 vs 1.6 roller rocker ?'s

[cornutz]

Can someone explain the major diff's between the two...

You see, I want to put a nice mild roller motor in the burb, and I would like to know what the deal is with the two... they seem to be very close, ie: one tenth off right? Also, why do some people on flea bay have sets for sale that have half 1.5 and half 1.6 ratio... Do they use one for the intake and one for the exhaust? and why do that?

Anyway, like I said I want to put in a hyd. roller cam, rocker, lifter setup into the balanced block that I have on an engine stand in the the garage, but I have never tried this route...any help would be appreciated, Thanks.

[68w/sbc406]

i am not a pro, but do know that the 1.6 rockers allow the valves to open farther. then you have to make sure that your springs wont coil bind and your valves wont hit the pistons. as far as a mixed set. no idea

[68Stepbed]

Give Comp Cams a call. compcams.com
They have a CamHelp line that you can call. There is a section in What's your problem in this month's issue of CarCraft. I would question the mixed set myself.

[vtblazer]

My understanding is by putting the 1.6's on the exhaust, their looking for better performance.
Heard of it but never tried it.
I have the 1.5 full roller rockers on a 350 in my blazer and always wondered if by putting in a set of 1.6's they'd be noticable/worth while installation.

[Harold Shepard]

With the 1.6 you make the cam think that it is a little bigger and the Sb chevy exhaust flow with stock heads is not that great, so the rockes cause the illusion of more duration on the exhaust side causing a bit of performance increase. This is not a seat of the pants increase that will be felt but will show across the board on a dyno. Big and small, it helps a little with exhaust flow. Usually a mixed set sells for more $ than a straight set. Harold

[VetteVet]

Here is a link that should help with your question.

http://www.chevyhiperformance.com/te...148_0207_rock/

[Old Yeller 1970]

When I was having my 350 rebuilt, I discussed having 1.6 rockers installed with my engine rebuilder. He said that since I was choosing a cam with lots of lift, there was no need for the 1.6 rockers. In other words the effect I wanted from the 1.6 rockers was being built into cam. He said that to then add the 1.6 rockers would increase the overlap more and cause my bottom end torque to suffer.
The cam in question was a custom ground 280 Magnum Comp cam with a 114 degree lobe separation angle instead of the more narrow one.
After you pick your cam then you should be able to decide, based on where you want your power band to be, whether or not to have 1.5 or 1.6 rockers.

[cornutz]

Thanks for the replies guys... I appreciate it...

[fastwillie 696969]

check out car craft mag. july 05 addition there a article in there covering this exact question

[68Stepbed]

I have the 1.5 full roller rockers on a 350 in my blazer and always wondered if by putting in a set of 1.6's they'd be noticable/worth while installation.[/QUOTE]


I've heard that changing from 1.5 rollers to 1.6 rollers, you would only pick up a few horses. Not enough to justify the expense. On the other hand, changing from a stock 1.5 to a 1.6 roller, you could pick up about 10-15 ponies.

[RPOZ11]

I am using 1.6 Comp Cams roller tip steel rockers on my 305 in a 1984 C-10. The influence I see is that you can use an aggressive cam up to .500 and still keep some vacuum on the Brakes system. The only time I see any difference is in the top end and I have a 700R/4 behind the 305. I think I like the 1.6 on the exhaust side on cams under .500....Just my experiences!