1.6 Rocker swap

[92ghost]

A question to the masses but mainly for the LT1 type engine. I have heard of swapping a roller rocker with 1.6 ratio in place of the stamped 1.5 ratio non-roller rocker to increase HP. I have read that Crane Cams has the only replacement type roller rocker that will fit under the stock valve covers. All others need modifications to the cover or an aftermarket style valve cover to accommodate. I have also heard that the GM style roller rocker found on the LT4 is self aligning but needs a guide plate to stabilize. Could this be a potential swap? I'm sure someone has done this swap. Also, if only the rocker arm swap is done, (1.6 for the 1.5) what kind of HP and Torque increas can be expected?
Thanks in advance for your comments.

 

[c4c5specialist]

Hi there,
I am moving this to c4 technical, as this is for 92-96 Corvette.
Allthebest, c4c5

 

[Edmond]

I have been told that you do get an increase in HP, but at the sacrifice of low end torque. Anyone know if this is true?

 

[Vettelt193]

I have done it all three ways... full set of 1.5's, full set of 1.6's, and 1.6 on the intake, 1.5 on the exhaust.... the mixed set works best in my opinion... you don't sacrifice the bottom end power, and you still get more on top. It is a great mod because you don't sacrifice anything... you get cooler oil temps, better gas mileage, more power!

No full rollers that I know of will work with the stock valve covers... you could go out and purchase LT4 covers, but that would be cost prohibitive... all you have to do is cut off the drip tabs, and there is really no reason why you would ever go back to factory, even if you show the car, I doubt they will ever look to see if you have the factory rockers under the valve covers.

 

[92ghost]

Thanks vettlt193 I appreciate your experience. I will most likely look into the 1.6 intake and 1.5 exhaust rocker swap as a winter project. I have replaced normal stamped rockers before and it is a snap. Is there any trick to doing the roller rockers?

 

[Vettelt193]

Just make sure you get the self aligning tips when you order them... in another post in these forums someone said you can buy sets of 8 from some company (TPIS??) so you don't have a whole extra set. (There used to be a company that sold mixed sets as well, but I think they are out of business)

You also may want to look into the LT4 hotcam kit before you buy the mixed set... entirely up to you though, just want to make sure you don't buy the mixed set then have to swap them later for a full set of 1.6's or 1.5's because you want a cam that requires something different.

Also, when you cut off the drip tabs be careful, because the valve covers are made from carbon fiber... you don't want carbon fiber strands getting into the engine.... other than that, the swap is simple, and worthwhile