Would like to install a new set of aftermarket rockers for my LS2 07'...read that going from 1.7 ratio to 1.8 would give me around 20 more horsepower..this is something simple to do and would be an improvement over stock. Any suggestions on what brand would be best to us. Also read that SLP had a good set for what I want.
LKicklight

 

You can't go wrong with Yella Terra. I think 20 hp is a bit ambitious, more
like 8.

 

I was one of the few who went from stock rockers to SLP's 1.85 rockers. The dyno showed some gain as I recall but at the track, no gains at all. IMO, not worth the cost of effort. I went back to 1.7's with my cam of course.

 

I had thought of doing that as well. After speaking with various people that build power, there was not many that like the idea of adding weight & mass to the valve train.

So I went with a ported Fast intake & TB, that was simple & noticeable.

 

I have Yella Terra Ultralite Shaft Mount Non-Adjustable Roller Rocker 1.7 Ratio. Love them

 

http://www.corvettefever.com/techart...rms/index.html

 

I installed the Vinci Crane Quick Lift rockers, 1.8 ratio.
There were three major reasons I opted to install rocker arms over a cam.

● I have a modest horespower goal.
● While I personally installed cam in my 2002 LS1 T/A, the cramped front of the 'vette looked like a nightmare for cam installation.
● Moving up to higher-ratio rocker arms is potentially worth some power-and is a quick and simple bolt-on that can be accomplished in less than a day, without opening up the engine.

Vinci Crane Quick Lift pros:
●Better geomentry for better results. (For explanation, see article below.)
●No interference with stock valve covers.
●Stiffer pushrods are also included in the Crane kit, as experience has shown that the stock soft pushrods are one of the LS-series engine's weak links.
●First CNC machined from super strength alloy, then treated with their "Mikronite" process to increase strength and durability by reducing stress-riser cracks and surface inclusions.
●They're purty!

Vinci Crane Quick Lift cons:
9 hp - - not quite Crane's claimed 20 hp, but then again the engine still has the stock cam with no drivability issues.
Because they employ poly locks and guide plates, this can scare some ppl as the valve lash must be adjusted manually. But follow the (excellent) instructions for zero problems.

Read an article on Crane Quick Lift rockers here: http://www.tomhenryracing.com/parts/features/quicklift/

Product page from Vinci Hi-Performance. http://www.vincihiperformance.com/NE...TS%20PAGE.HTML

My Dyno sheet. Before and after Vinci Crane Quick Lift rockers, no other mods. Since dynos took place some time apart, YMMV.

 

Before I went the cam/heads route I had the Crane 1.8's. I put them on at the same time as other mods, so I have no idea what they contributed to power. With headers, an unported FAST 90, a Honker, the 1.8's/springs and very mild tune (11.7 AFR) -done mainly to eliminate torque management, I got 389/387 on a Dynojet 248. I now have Harland Sharps because the tuner that installed my TF 225's recommended them. The next time I do something to the engine, I'll replace the rockers with Crane 1.7's to take advantage of the "Quick Lift" feature. I finally found an article that showed the Cranes on the TF heads, so I know that it can be done.

Based on what I have read on this forum and elsewhere, replacing the stock rockers with Crane 1.8's and no re-tune you should get 14-15 HP. With a re-tune, you'd get a little more. I recognize that the real-life results in this post are on the low side.

 

Believe me, I don't have an answer for the low 9HP, unless it has to do with variations due to the 2nd dyno being done some time later.
I've yet to write Rodger Vinci about the discrepancy.

 

I replaced mine with Comp Cams 1.85's. Afterwards, I definitely noticed and increase in pull....I haven't dyno'ed, yet, but I can feel a 15-20 HP difference in the seat of the pants. IMO, for about $200, they are worth it.

 

Personally, I would not go for the 1.8 rockers but instead would spend a little extra for a cam and a nice set of 1.7 roller rockers.

 

I wouldn't worry about that difference too much. You got 9 HP and the difference could be due to a change in dyno calibration accuracy.