Benefits of roller rockers.

[juicehead9]

Re: Benefits of roller rockers.

i'll keep looking, i want 94-95 l35's right?

 

[Black Knight]

Re: Benefits of roller rockers.

i'll keep looking, i want 94-95 l35's right?

Yep :tup:

 

[juicehead9]

Re: Benefits of roller rockers.

I have some z28 valve springs would they work on some l35's? What is the flow number of the L35's I know stock is like 164, and vortec's are like 260, what is the flow of L35's?

 

[gjp]

Re: Benefits of roller rockers.

flow on stock l35's are around 180 I think.

 

[juicehead9]

Re: Benefits of roller rockers.

o should I go wiht the l35's or just work the stock heads, bigger valves some port work?

 

[Black Knight]

Re: Benefits of roller rockers.

o should I go wiht the l35's or just work the stock heads, bigger valves some port work?

Don't even waste your time or money on the stock heads unless you're paying someone to pull them off and turn them into paper weights. You could spend the time and money to build a set of L35's but IMO if your gonna spend all that time and money, you might as well do it to a set of vortec's then spend the extra $400 to have them fitted to your truck. Then you should be good to go in that department for a long time.

 

[myclone]

Re: Benefits of roller rockers.

Lift yes, duration no with stock lifters. My poor math but It looks like 6.66% more lift. I'd vote for the 1.6 on the intake as well on a stock cam.

You do gain some duration with higher ratio rockers. Not much but its there.

 

[Black Knight]

Re: Benefits of roller rockers.

Lift yes, duration no with stock lifters. My poor math but It looks like 6.66% more lift. I'd vote for the 1.6 on the intake as well on a stock cam.

Hey Don, can you or anyone explain show me the formula you used to get this number?

 

[dgoodhue]

Re: Benefits of roller rockers.

Rockers are a ratio 1.5:1 and 1.6:1. The stock cam is .351/.387 So if you divide .351/1.5, you will find the actual intake cam lobe is 0.234. To find the cam lobe with 1.6:1 rockers, its 1.6 * .234 = .374

How did he come up with an increase of 0.067, if you remember your math class the percentage increase would be (1.6-1.5)/1.5 =.067 Either way works for calculating the new lobe.

 

[ranger]

Re: Benefits of roller rockers.

Hi folks,

With regard to Black Knight's comment about 1994-95 being the best year to get for the L35 heads, what makes those years so advantageous? I thought L35s were pretty much all the same?

Regards,

Craig Stangohr
Sy 1563
12.71@106.42 @18 lbs.

 

[Black Knight]

Re: Benefits of roller rockers.

Rockers are a ratio 1.5:1 and 1.6:1. The stock cam is .351/.387 So if you divide .351/1.5, you will find the actual intake cam lobe is 0.234. To find the cam lobe with 1.6:1 rockers, its 1.6 * .234 = .374

How did he come up with an increase of 0.067, if you remember your math class the percentage increase would be (1.6-1.5)/1.5 =.067 Either way works for calculating the new lobe.

Thanx Dave,

I'm still trying to figure all this cam stuff out. So a stock cam lift is .351 and duration is .387, what do these numbers mean? The cam lifts up .351 of an inch from center or ??

Hi folks,

With regard to Black Knight's comment about 1994-95 being the best year to get for the L35 heads, what makes those years so advantageous? I thought L35s were pretty much all the same?

Regards,

Craig Stangohr
Sy 1563
12.71@106.42 @18 lbs.

Up to '93 the 4.3's came with LB4's, '94-'95 came with L35's, and 96+ were vortec's ( atleast that's what I remember ) so to answer your question '94-'95 are the best because they're the only years.

 

[dgoodhue]

Re: Benefits of roller rockers.

Thanx Dave,

I'm still trying to figure all this cam stuff out. So a stock cam lift is .351 and duration is .387, what do these numbers mean? The cam lifts up .351 of an inch from center or ??

The .387 is the exhaust lift. Physically the cam lobes lift the valves .351 & .387 with 1.5:1 rocker at their peak. The stock duration is something like 155/175 @ 0.050 lift(intake/exhaust), but I am just going off memory, its a very small amount when comparing aftermarket cams. Sometime you will see duration numbers @ 0.006 lift.

 

[Black Knight]

Re: Benefits of roller rockers.

The .387 is the exhaust lift. Physically the cam lobes lift the valves .351 & .387 with 1.5:1 rocker at their peak. The stock duration is something like 155/175 @ 0.050 lift(intake/exhaust), but I am just going off memory, its a very small amount when comparing aftermarket cams. Sometime you will see duration numbers @ 0.006 lift.

Told you I don't know anything about cam stuff :rotf: but it's starting to make alot more sence.

After a bunch of Googling, I found this info for anyone else that doesn't fully understand what these numbers mean and affect.

http://www.popularhotrodding.com/enginemasters/articles/hardcore/0606em_camshaft_specs/index.html

http://www.chevyhiperformance.com/techarticles/53439_cam_basics/

http://www.hottr6.com/triumph/CamBasics.html

 

[ranger]

Re: Benefits of roller rockers.

Hi folks,
someone can correct me if I'm wrong, but I think the L35s came in vehicles as early as 1991. They were the ones that had the central injection system, also known as "the spyder." Most of the spyders had trouble at some point, so it was not the best sytem, IMHO. Better than throttle body, but not as good as direct port injection.

Cheers,

Craig Stangohr
Aiken, SC
Sy 1563
12.71@106.42@18lbs

 

[nallj92]

Re: Benefits of roller rockers.

yeah l35's came eailer than 94, i have 92 L35's

 

[Black Knight]

Re: Benefits of roller rockers.

Good to know, pretty assnine they didn't put them on the SyTy's.