l03 POS cam...

"Lift"
intake .351
exhaust .386

with 1.6 rollers rockers that should be something around this .380/412 lift...


well this do anything for me? how much of a diffrents can i see in something like that... in power or what not... how about the computer?

 

The swap is very much so worth it on the peanut cam. I say go for it.

No changes to the ECM are needed.

 

1.6's will be the way to go if u are not lookin to put in a new cam!! Your about right for the lift so I would say go for it to!! But with what you have done so far u should have PROM tuning done!!

Jason

 

there's an easy way to calculate the difference in lift between 1.5 and 1.6 rockers.

take the lift with 1.5 rockers, divide it by the old rocker arm ratio (1.5), then multiply it by the new rocker arm ratio (1.6)

so, your intake lift would be: .351 / 1.5 * 1.6 = .374

your exhaust lift would be: .386 / 1.5 * 1.6 = .412

duration is not affected. since duration is what affects manifold vacuum, and that is what your map sensor reads, there shouldn't be a major chance in the ecm's tuning. however, the biggest gain you'll see, even with NO mods, is in tuning the ecm. before you do anything else, you should learn to do that.

 

Duration is effected, but then again, it isn't. The actual seat to seat isn't affected. However, there is a change in .050" duration, in a sense. With 1.5 rockers, the valve is open .075" at .050" tappet lift (where the .050" duration is taken). With 1.6 rockers, the valve lift is .080". Therefore, the larger ratio accerates the valve action in a way and simulates slighty larger duations without actaully changing the duration ground into the cam. The lazier the ramp rates, the larger the gains in .050" duration are. With the peanut cam, i would expect about 3-4° increase, so its fairly substantial, in terms of a simple and on part.

 

will i see anymore HP and TQ from this... about how much more?

 

umm yes, it's a good gain

 

if u dont want to dump alot of money on roller rockers look at enginekits.com for vortec roller tipped rockers, self aligning for centerbolt heads, only $90. And at sdpc2000.com they sell Federal Mogul stamped steel rocker arms self aligning for centerbolt heads for only $74. I put the federal mogul ones on my car and had a pretty good increase in power. Well worth the money.

 

well i destop dyno a cam, "LT1"

13.675 in the 1/4 "1.5"

13.654 in the 1/4 "1.6"


thats .021 diffrents
is that about right?

now try to convert that in to HP... what abouts would that be?

 

no

 

so no ones got hard numbers, or what this well really do other then raz the lift a tad...

 

i gained 2 tenths and an MPH in the quarter mile. I made a bunch of runs before the 1.6 rockers and my best was a 15.018, after the rockers and going from 6* to 8* advanced timing i went to a best of 14.791.

 

what mods have you done to run high 14's ...

 

DIFFERENCE!!!

with a C!

 

There is only one way to figure out how much improvement any mod will make. That is by strapping it to a dyno and running it down the track. You are going to have to get that through your head.

 

Probably about 3-4 HP by itself.
Do full exhaust and you'll get an even better boost too, from the exhaust valve being open a little farther/longer.

 

I just put 1.6 roller rockers on took .5 off the 1/4.
Befor

R/T .223
60’ 2.447
1/8 10.069
Mph 70.78
1000 13.052
¼ 15.553
Mph 90.22

After

R\T .052
60' 2.317
1/8 9.737
MPH 73.71
1000 12.611
1/4 15.033
MPH 93.09

 

I was under the impression that most the power came from the 'roller' part of the 1.6 full on rollers.

-chuck

 

no, the bigger ratio gives you more lift.

 

Correct. However, even switching to roller 1.5 RR's can increase power. They are more precise and do not flex like the stockers. The stockers can be anywhere from 1.3x to close to 1.5. They are junk.

 

Id skip anything made of aluminum on a street motor. It can fail as aluminum doesnt posess infinite fatigue life (provided the stresses are low enough) like ferrous metals do. I always wanted a good set of pro mags http://www.compcams.com/Technical/Cu...g/HTML/311.asp but Im still to broke to afford them.