are they possible to change with the head on the car?

 

i've heard of people doing it. with the proper pulling tool. along with pressurizing the cylinder so the valve doesn't fall.

 

I've done both methods on the ecotec and yes they are, it's a bitch to do, you will need 2 people or be very skilled yourself.

 

This.

I was all ready to swap valve springs this winter, and spoke to a lot of engine builders in my area about it. You will need the following tool to compress the valve springs:

CF-300<BR />Valve Spring Compressor for OHC and DOHC | Item #CF-300. | Goodson Tools & Supplies for Engine Builders

Like exsoccer said.... you need to use an air compressor to keep the valves from dropping when you remove the springs.

 

Exactly, done it too!

 

That's a way cooler valve spring compressor tool than i have ever used.

 

That's the valve spring compressor tool listed in the LSJ build book

 

Thats the same tool I used to do my supertechs earlier this year with the head on the car. Compressed the cyl with air from my compressor. Just be careful with the damn tiny valve keepers. Make sure you use a magnet to pull those off and keep it handy when your putting them back on. I def needed help from a friend to do it.

 

confused how are you pressurizing the cylinder

 

Get one of those long crazy straws. Remove plugs and blow like hell while removing spring. It's hard but rewarding.

 

I used the bit that screws into the spark plug hole cant remember were I got it from, attached to my air line connected to my compressor. I had the compressor on real low, I think like 10-15 psi. Just enough to keep the valve from dropping.

 

You can run it higher (if you want), engine compression is well over 100 PSI... During combustion it is MUCH more...

 

I honestly dont remember how high it was. Im pretty sure it was low and that did the job just fine, but I get what your saying. My buddy had the bit that we used. Not sure if it came off some compression tester or A/C recharge fitting lol

 

The $25 compression tester from auto zone will work with the schrader valve removed plus the end will hook up right to the quick connect of any standard air hose.

 

That tool is the pain in the ass way of doing it. I used that one for the intake side but i used the other tool for the exhaust side, MUCH easier!
We used this when the head was off too...

EuroExport Valve Spring Compressor Tool Summer Sale

 

What version of that comperssor did you use? or was that just an example?

 

x2

 

That same exact one... the 4g63. Sorry it has to be modified, gotta drill the hole in a little bit and thread them, but that's not too hard to do.

 

Thanks

 

I'm about to use this one. KENT MOORE J-43649 GMT900

 

These are what I'm using.... (same compressor as u)

https://www.cobaltss.net/forums/part...holder-264319/