Budget vs. Premium Heads
How about Tattoo? I thought it was pretty decent. No "over the bar" rum really compare to the Caribbean sugar cane rums that I drank in the bahamas, but thats a subject for a totally different thread. 
There's definately a lot of different options for guys wanting cylinder heads for there ls based engines! We recently dyno tested several different out of the box cylinder heads with very interesting results. The PRC Stage 2.5 5.3l head made better power out of the box than a popular 205cc aftermarket casting we tested. The PRC ships with a 62.5cc chamber while the 205cc had a 66cc chamber. If the heads had been milled to the exact same chamber size the power would most likely have been identical. During these tests we also had time to make a few dyno pulls on the new PRC casting. While it's still in development & not exactly where it needs to be, it did offer a glimpse into it's power potential. The PRC 215 head made a additional 15hp or so arcross the mid-range of the dyno pull. It slightly decreased that margine up top, but hopefully some changes to the valvejob & short-turn will help us to keep that 10-15hp advantage.
Is a 10hp gain worth spending $1000 more for a new PRC casting when the PRC 5.3l Stage 2.5 head did so well in dyno tests? Probably not for everyone especially when the out of the box 5.3l head can run heads up with it's major competitors small runner products with ease.
What camshaft do you plan on running with your cylinder head purchase?
Is a 10hp gain worth spending $1000 more for a new PRC casting when the PRC 5.3l Stage 2.5 head did so well in dyno tests? Probably not for everyone especially when the out of the box 5.3l head can run heads up with it's major competitors small runner products with ease.
What camshaft do you plan on running with your cylinder head purchase?
__________________
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Thread Starter
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From: Las Vegas, NV
In an article by GM High Tech Performance, our factory 243 casting which is CNC'd in-house was compared to the AFR, Dart, Edelbrock, and Trickflow heads and came in second to the Trickflow. The Trickflow made only 8 more HP than our factory casting on the engine dyno.
In the article, they stated "On the flow bench, the Livernois LS2 head kept right up with the out-of-the-box aftermarket units, flowing in excess of 320 cfm at .600-inch lift. And that doesn’t come at the expense of good low lift flow, so the torque and good street manners are still there."
In the article, they stated "On the flow bench, the Livernois LS2 head kept right up with the out-of-the-box aftermarket units, flowing in excess of 320 cfm at .600-inch lift. And that doesn’t come at the expense of good low lift flow, so the torque and good street manners are still there."
Heck, I'll just have another Captain 'n' Coke. After the 5th or 6th round I can't tell the difference anyway.
Thread Starter
TECH Addict
Joined: Jun 2002
Posts: 2,428
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From: Las Vegas, NV
<How about Tattoo? I thought it was pretty decent. No "over the bar" rum really compare to the Caribbean sugar cane rums that I drank in the bahamas, but thats a subject for a totally different thread. >
Maybe not.
>Maybe not.
1Bad we can do a 64cc chamber on the 5.3l if you'd like, but it is a custom order!
Here's the 3 cylinder heads tested next to each other. Notice the Stage 2.5 5.3l heads outpower the small runner 205cc cylinder head. If the 205cc head was milled to 62.5cc chambers like the 5.3l head then my bet is the power output would be identical. Our goal was to test out of the box cylinder heads.
The PRC 215 head has a 61.5cc chamber and will ship with better than stock p/v! As a result you will be able to mill them as far as 59cc chambers & still clear have stock p/v!!
Here's the 3 cylinder heads tested next to each other. Notice the Stage 2.5 5.3l heads outpower the small runner 205cc cylinder head. If the 205cc head was milled to 62.5cc chambers like the 5.3l head then my bet is the power output would be identical. Our goal was to test out of the box cylinder heads.
The PRC 215 head has a 61.5cc chamber and will ship with better than stock p/v! As a result you will be able to mill them as far as 59cc chambers & still clear have stock p/v!!
__________________
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
Jason
Co-Owner, Texas Speed & Performance, Ltd.
2005 Twin Turbo C6
404cid Stroker, 67mm Twins
994rwhp/902lb ft @ 22 psi (mustang dyno) www.Texas-Speed.com
1Bad we can do a 64cc chamber on the 5.3l if you'd like, but it is a custom order!
Here's the 3 cylinder heads tested next to each other. Notice the Stage 2.5 5.3l heads outpower the small runner 205cc cylinder head. If the 205cc head was milled to 62.5cc chambers like the 5.3l head then my bet is the power output would be identical. Our goal was to test out of the box cylinder heads.
The PRC 215 head has a 61.5cc chamber and will ship with better than stock p/v! As a result you will be able to mill them as far as 59cc chambers & still clear have stock p/v!!
Here's the 3 cylinder heads tested next to each other. Notice the Stage 2.5 5.3l heads outpower the small runner 205cc cylinder head. If the 205cc head was milled to 62.5cc chambers like the 5.3l head then my bet is the power output would be identical. Our goal was to test out of the box cylinder heads.
The PRC 215 head has a 61.5cc chamber and will ship with better than stock p/v! As a result you will be able to mill them as far as 59cc chambers & still clear have stock p/v!!
