upgrading valvetrain

[RFxCamaro]

Forgive my ignorance but i have never had a cammed car. I'm going with a gt2 cam and heard i need to upgrade my valvetrain. Can i grab the valvetrain out of something like a supercharged gtp and call that good enough? Do the sc engines or series 3 engine have better valvetrains? I ask because i see plenty of gtps at the junkyards.

[ssms5411]

Re: upgrading valvetrain

GTP's have the same valvetrain, might look at ZZP and get COMP 105lb springs.

[RFxCamaro]

Re: upgrading valvetrain

any other cars that i can grab parts from for an upgrade?

[ssms5411]

Re: upgrading valvetrain

I would just go with the Comp 105lb springs.

[87SC/SS]

Re: upgrading valvetrain

+1 on the Comp springs. Spring loads really need to be up to snuff to avoid floating the valves. Make sure you check valvetrain geometry when your done - you may need longer or shorter push rods. If the geometry is off it could damage the valves, guides, and/or seats. I put an Edelbrock RPM cam in my 3.4 and ended up having to put in different pushrods.

Checking the geometry is pretty easy - install the cam and install one intake and exhaust valve with springs and retainers. Put an even coat of grease on top of the valve and install the pushrod and rocker - set lash and manually turn the motor over 1 or 2 revolutions. Take the rocker out and see where the wear pattern in the grease is. It should be right in the middle of the valve. If it isn't you should swap out the pushrods - I purchased an adjustable length pushrod from Summit to determine what length I needed. Through trial and error I got the pattern just right, checked it with a caliper and ordered the closest matching pushrods I could find - they ironically happen to be Ford Motorsports, but they work just fine. Make sure when you get the pushrods you check again to make sure you ordered, they sent, and you measured correctly.

Also if you really want to get picky you could match spring height and pressure using a micrometer and spring shims. It's not usually necessary, but I consider it part of doing the job right.

Lunati has some really good valvetrain articles: http://www.lunatipower.com/Tech/Default.aspx

Just my $.02

Good luck

[ssms5411]

Re: upgrading valvetrain

With the GT2 cam he'll be good with stock pushrods unless he wants some stonger pushrods which Comp sells also.

[01PewterDropTop]

Re: upgrading valvetrain

I ran my GT2 cam on stock valvetrain for 2 years with no troubles. i raised the shift points by 200 RPM. now i have the CC105 springs, ZZP's 7.050 pushrods, CC OER Lifters and 6400 shift points still fine tuning it with the ported/milled heads it sounds awsome with the true duel borlas

[jimfire]

Re: upgrading valvetrain

Forgive my ignorance but i have never had a cammed car. I'm going with a gt2 cam and heard i need to upgrade my valvetrain. Can i grab the valvetrain out of something like a supercharged gtp and call that good enough? Do the sc engines or series 3 engine have better valvetrains? I ask because i see plenty of gtps at the junkyards.

Good to see that you realize when upgrading that you also take other options into consideration, smart guy!!:rock: