Do I absolutely without a shadow of a doubt need better springs when installing 1.6 or 1.7 rockers? Back in the GTP world, we would swap from stock 1.6 to 1.9 and always we could use the stock springs. We raised the shift point 2-300rpm and it was still fine. Are the stock LT1 springs really maxxed out in factory form, or are people just being a bit too extreme on precaution? I'm not going skyhigh with the shift points either, just to 6200.

 

A stock lt1 is going to hit the peak HP well below 6. The stock springs are marginal and you will most likely beging to float even before peak. Going to a higher ratio/lift rocker will require even more of a spring to control the valves.

Even if the stockers could handle the extra lift, you would not maximize your power from the higher lift and duration effects of the higher ratio rocker. JMHO.

 

Compareing a blower engine to an N/A is mistake #1
From what I have heard, the stock springs were to weak from the factory for the stock cam.

Not sure what LT4 springs are rated at, but maybe look into them, they are like $40.
(check rateing on them)

 

Add 1.6 rockers and you are .030" from coil bind (under what most people recommend as minimum[.050"]. Add 1.7 rockers and you are going to bind and probably break every spring and possibly destroy your engine with a dropped valve.

Two different engines most likely don't have the same spring specs (installed height, coil bind height, etc.). Not wise to compare that way.

IMHO, the valvetrain is the worst place to compromise with parts. Why people want to take chances with it, I don't know. Putting more stress on worn out stock springs is a poor recipe. 1.6s will run on a stock spring, but is it worth the risk?

 

Thanks guys, thats why I asked. I wanted to know why and what would happen. I know the L67 and LT1 are different, but they are similar. I was just saying what I know of rockers and springs.

I'm not concerned with the money part of the springs, just the install of the springs. It's not fun and it's a 2 person job for sure. On the GTP we used a compressor and kept the valves from falling. How do you guys change out the springs? The same way?

 

Yes, you will need a compresser. Perhaps the morroso will do the job. Make sure you reseach on here for the best compresser to buy or rent.

If your piston is TDC the valve should only drop 1/4" and not all the way into the cyl, however some have either held the valves up by useing compressed air in the plug hole or pushed some cord into the plug hole. But as mentioned it is a lot easier if you put the piston at TDC.

whatever type spring compresser you get, make sure it will fit the springs that are hiding under firewall lip---do a search.

 

How are they similar? I know next to nothing about the L67.

 

Just for clarity sake: In re CompressOr, as in air compressor to hold up valves and "CompressEr" as in Spring Compresser to compress the springs to remove locks and retainers. So yes to CompressEr, but not necessarily yes for compressOr, if you put the pistons at TDC.

 

918 beehive springs work well with the proper hardware (search for part #s)

 

Pushrod motor. The technology, obviously minus the supercharger. Rockers and springs and pushrods. I used LS6 springs when I went from the stock rockers to 1.9. On the l67, we didn't have to upgrade springs if staying close to the stock shift point. I went up 500 rpms.


And yeah, a compressor through the spark plug hole. We did that on the GTP motor. It had much easier access to the plug holes than the LT1. But if thats the way to do it.

 

You can take the heads off as well its not a lot more work to get them off and it is nice to have the heads right in front you to do the springs makes it go much faster you wont have to keep moving your air hose