roller tip rockers

[SmokinBBC]

Ahhhh....but HOW MUCH power are we taking about? Typically, hot rod rags will claim 16 horsepower increase by installing the most expensive (of course!) roller rocker setup. But one has to look at the ENGINE the roller rockers are being installed on FIRST to see WHY they get the horsepower gains. If you are driving a REALLY hot, high-revving engine, then certainly roller rockers would be a good investment. Something like DZRick's old Z-28 would be a good example of that. A solid lifter engine that is already capable of revving to 8000+ RPM. But if you are driving a Caprice-engined smogger Vette from the mid-to-late 70s, you would just be wasting your money.
Maximum HP increase would probably be less than 10. Better off installing a couple of Cherry Bomb glasspacks

I wonder which, if any, modern production engines have roller rockers.

 

[DJ Dep]

I wonder which, if any, modern production engines have roller rockers.

I'm not sure, but I think the C5 Vette engines have them. Which they should, since they can reach some pretty high RPMs. They also have the cross-bolted main bearing caps (a Ford invention).

Worship79: Depends on how hot your engine is. If you are driving ABOVE 6000RPM most of the time, I would say yes, go for them. If you are just cruising around town with an occasional blast at the strip, then I'd say spend the money on some roller rocker decals, and buy some pizzas too.

 

[guru]

Lets be very very clear here.

The LT4 made in 1996 had full roller rockers. GMPP sells them if you want them.

The LS series motors has roller trunions, and a regular tip.

Almost all the benefit of a roller rocker is in the truniun and not the tip.

 

[big2bird]

Lets be very very clear here.

The LT4 made in 1996 had full roller rockers. GMPP sells them if you want them.

The LS series motors has roller trunions, and a regular tip.

Almost all the benefit of a roller rocker is in the truniun and not the tip.

Yep. That's a fact, and I totally agree with Guru here.

 

[MYBAD79]

I'm using Comp 1.52 ratio roller tip rockers that I got cheap ($50)..... I would not spend $180 or so for them.... I am considering 1.6 ratio rockers and I'm on the fence : $50 for stamped steel or $80 for roller tip (both Summit) ... $30 isn't all THAT big of a price difference....
I have tall covers and I did not have any problems with the roller tip rockers that I use now..... dunno... I probably buy the fancy roller tips so just in case I do install clear plastic valve covers I have something nice under there.... :idea::beer:

 

[Twin_Turbo]

Summit brand = made in China, do NOT buy!

 

[Worship79]

My setup is 64 cc performer heads, CC XE268H cam, stock cast alu pistons, 1.52 roller tip rockers, TH350, 3.55 rear gears, guestimate compression around 9.0:1.

I want to upgrade to flat-top pistons and 1.6 ratio rockers, cars purpose is streetcruiser/occasional sprint/have as much fun as possible :amused:

Just checked: CompCam only has roller tip 1.6 rockers ($157,95) or full rollers ($269.95). I see Lunati offers stamped steel rockers for $160.99, any opinions on this brand? Other suggestions perhaps?

 

[Worship79]

I calculated the extra lift going to 1.6 ratio: could someone check these numbers? What kind of performance gain would/could this mean? Or shouldn't I bother?

Intake:

0.477 / 1.52 = 0.314

0.314 x 1.6 = 0.502

0.025 more lift

Exhaust:

0.480 / 1.52 = 0.316

0.316 x 1.6 = 0.505

also 0,025 more lift.

 

[enkeivette]

I just posted another thread about this... my roller tips no longer roll freely. They feel like the pins that hold them in have flat spots. But the needle bearings in the fulcrum feel fine. They rock back and forth easy. Should I even bother getting new ones?

Worship, yes your math is correct. It really depends on your heads. I have a program that will tell you whether or not you've maxxed out the flow of your heads with the valve lift that you have currently if you have the head flow data across the rpm range. (You should be able to find it on the internet)

 

[Twin_Turbo]

I would rather have roller fulcrum than tips. The LS engines only use a full roller fulcrum.

What do you mean with tight? Are they seazed? I've never had a set that rolled very smooth, they all feel a little rough. it's just a steel needle in an aluminium hole.

 

[enkeivette]

TT are you talking to me?

The roller tips no longer roll smoothly. I'd guess that the steel needle has created a groove in the aluminum hole, so when I spin the roller it feels rough... sort of how it feels when you try to turn over a motor by hand with damaged bearings. It will spin freely intermittently, but then it feels like it snags on something internally.

 

[Worship79]

Worship, yes your math is correct. It really depends on your heads. I have a program that will tell you whether or not you've maxxed out the flow of your heads with the valve lift that you have currently if you have the head flow data across the rpm range. (You should be able to find it on the internet)

Thanks! I went to the dyno yesterday and unless I put in some decent pistons I really needn't bother with higher ratio rockers. What I do need to bother with is why my engine only runs on 7 cilinders under load... 205 rwhp is way too low for a 350 SBC with performer heads, eps intake, xe268h cam, 1.52 roller tip rockers and 750 cfm carb. :crutches: