LS6 vs AFR Heads...

[Z06 Tom]

Phil over at "Dynotech" just shot me some pics of the AFR heads he's getting ready to put on my Z. He'd previously sent me some pics of my stock LS6 heads after he removed them so I could post them when I put them up for sale. The AFR's sure are a work of art...

The AFR Heads:

Stock LS6 Heads:

These stock heads have Comp Cams springs in 'em, but the AFR's with duel springs sure look a lot beefier!!

 

[slong]

Very nice tooling.

 

[Edmond]

Aren't AFR heads the premier heads out there?

 

[Z06 Tom]

Aren't AFR heads the premier heads out there?

That's what I've been told. I'm not gonna get any valve float on those suckers on the big end!

 

[Edmond]

Tom,

Are you going to replace the cam as well?

 

[Z06 Tom]

Tom,

Are you going to replace the cam as well?

It already has a custom grind blower cam in it.

 

[Edmond]

It already has a custom grind blower cam in it.

Nice! What kind of power numbers are you expecting?

 

[Z06 Tom]

Nice! What kind of power numbers are you expecting?

I'm hoping for around 640 at the wheels. Torque should come in around 525 or so. The T-trim compressor is more efficient than the S-Trim, so the curve should be much better as well. Man, I can't wait 'till Spring!!

 

[Edmond]

I'm hoping for around 640 at the wheels. Torque should come in around 525 or so. The T-trim compressor is more efficient than the S-Trim, so the curve should be much better as well. Man, I can't wait 'till Spring!!

Don't know how the weather is where you're at, Tom. But we're having a pretty mild winter here in Chicago. But you know what they say, "Winter is the time to work on it and summer is the time to drive it."

I'm assuming that isn't a stock clutch trying to handle 640 to the wheels, which would be more than 750 at the flywheel.

 

[TODD L GRIFFITH]

Nice looking heads! Are those heads milled? Interested on knowing what size intake and exhaust port sizes over stock. Good luck with them.
Hey Tom I almost forgot. Are those valves larger than stock?

 

[Z06 Tom]

I'm assuming that isn't a stock clutch trying to handle 640 to the wheels, which would be more than 750 at the flywheel.

Yeah, it has a Spec stage 3 in it right now. It also has an aluminum flywheel, built tranny and a built 3:73 rear end (with DTE brace.) Here's a link to an old thread I posted on the build over on Z06Vette.com:

http://www.z06vette.com/forums/showthread.php?t=41950&highlight=Transformation+begins

Nice looking heads! Are those heads milled? Interested on knowing what size intake and exhaust port sizes over stock. Good luck with them.
Hey Tom I almost forgot. Are those valves larger than stock?

I'm not sure about the port sizes or if the valves are larger or not Todd. I'm pretty sure the valves are a bit larger, but I don't know how much. I'll find out though and post back. They are supposed to reduce my cr to around 10.0-1. I'm planning on running around 9lbs. of boost.

 

[Z06 Tom]

Here's what Phil over at Dynotech replied to the questions:

No, these particular heads are not milled for your application, they are
"as-CNC ported" from AFR and the valve sizes are standard upgrade sizes
from AFR.

 

[TODD L GRIFFITH]

Sounds like your combustion chamber is larger than the stock 64.5cc LS6 head. If you are supercharging, that is a step in the right direction for sure to avoid having to run 100 octane. I wish you the best, and can't wait to see the dyno results.

 

[Hib Halverson]

I'm hoping for around 640 at the wheels. Torque should come in around 525 or so. The T-trim compressor is more efficient than the S-Trim, so the curve should be much better as well. Man, I can't wait 'till Spring!!

I'm curious...with 640 at the wheels, what are you doing to improve the reliability of the trans and axle?

 

[Jeffvette]

These stock heads have Comp Cams springs in 'em, but the AFR's with duel springs sure look a lot beefier!!

What are the springs dueling over?

Cool pics. Good luck.

 

[Z06 Tom]

I'm curious...with 640 at the wheels, what are you doing to improve the reliability of the trans and axle?

Hey Hib,
The trans has been beefed up with steel shift forks (like the Viper) and a few other goodies. The clutch is a Spec stage 2-3 hybrid with an aluminum flywheel. The rear end is a HD unit built by Dynotech with 3.73 gears and hardened output shaft. I also have the Dynotech rear dif. brace on the car.

Shot with her guts hanging out:

Upgraded T-Trim blower (my existing S-Trim with new gears):

 

[Z06 Tom]

The heads are on the motor, won't be long now:

Ahhhhhhhhhh! It's HEADLESS!:ugh

That's better:

 

[TODD L GRIFFITH]

Damn, the suspense is killing me. It reminds me of being 8 years old waiting for Christmas day to arrive. I'm sure you are feeling it too. It sure is nice knowing that it is being done absolutely correct with excellent tuning ability. I was drooling, looking at their facility, very clean. That first drive home must be going through your imagination. Don't let stupid traffic spoil it. Bringing a video camera with you is probably too much to ask lol! We all want to share in the experience with you, or should I say, you to share your experience with us. hehe!
Good luck with it soon!
Todd

 

[Z06 Tom]

We all want to share in the experience with you, or should I say, you to share your experience with us. hehe!
Good luck with it soon!
Todd

Thanks Todd! They ran into an alignment issue with the serpentine belt after the heads were installed. The AFRs are slightly shorter than the stock heads. When they put it all back together, it ate the belt. They've got it worked out now, and put on a heaver duty tensioner to keep things in place. When you re-locate the the belt driven components (like the Vortech kit does) and bolt it all back on the motor, things have to line up exactly. The spacers that come with the kit don't work with the AFR heads. These pics from the initial install show how critical alignment is.

 

[TODD L GRIFFITH]

Yeah, I know exactly what you mean about the alignment being very critical. This is good experience for them too I expect. With the exact setup as yours, they will have a build sheet in place to look back on. They seem organized, so it is probably a computer file. Sweet! How are you fairing without the car with the weather getting nicer, day dreaming? lol! This is just the beginning to long sunny days and you'll have it back before you know it.

Cya,
Todd