I have been kicking around the idea of planting a set of C5R heads on my SS. I am prepping the car for open road racing so I will need alot of top end flow. I am pretty sure they will bolt right on to the standard LS1/LS6 motor but am a little unsure about the intake. Do these heads require a custom intake manifold or will a standard LS6 intake work. Also who or where can I get a set of complete heads? I have heard that the flow numbers on these heads are astronomical but havent seen any flow charts or numbers from anyone yet. any info would be greatly appreciated.

 

They will bolt right onto your LS1 block, but do not have a few of the accesory mounting holes. The heads are also not sold complete that I know of, they do not even have valve seats/guides in them. Figure around $4500 for the bare heads <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

They require a custom intake to be fabricated. Go ahead and figure another $2500 for that.

Tony

 

for the 4500.00 spent on them does anyone think the performance is worth the cost? Or would a rippin set of MTI/ARE heads sound a little more cost effective for the power

 

Here is how they arrive from GM, fresh out of the box:

http://users.ev1.net/~ynot_dv8/C5Rchamber1.jpg

http://users.ev1.net/~ynot_dv8/C5Rexhaust1.jpg

http://users.ev1.net/~ynot_dv8/C5Rexhaust2.jpg

http://users.ev1.net/~ynot_dv8/C5Rintake1.jpg

http://users.ev1.net/~ynot_dv8/C5Rintake2.jpg

I wouldn't even consider them unless you plan on building a badass big cube motor. Either that or a very hairy solid-roller 346ci setup that pulls out to 8K rpm.

When you factor in the cost of the valves, seats, springs, custom Jesel rocker arms ($2500), guides, retainers, etc... you are looking at well over $8K for the heads - without porting! Definitely reserved for the hardcore of the hardcore, too hardcore for me even!

Stick with LS1/LS6 heads from one of the proven shops and you will be just fine.

Tony

<small>[ May 24, 2002, 10:35 AM: Message edited by: Nine Ball ]</small>

 

<img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> HOLY CHRIST ALMIGHTY!!!! those ports are like the grand canyon! I have got to see flow #'s on those things. I wonder what a small port and polish job would produce on those things?

 

The set that MTI ported for Colonel's next motor flowed over 390 cfm on the intake at his cam lift. Made my 335 cfm LS6 heads look severely dwarfed when comparing area under the curve LOL!

Tony

 

They are expensive as hell but speed costs money and I wont deny that for a second. In open road racing you have to have the power to get into the 180+ speed range in our Fbodys. I did the silver state classic challenge last sunday in a 02 C5 and it was flawless at 160mph. But it has a huge aerodynamic advantage over ours. I will have to build the motor to overcome the aerodynamics issues. Right now I am in the process of laying the car out on paper and attacking the individual areas one at a time. But the motor is going to be an on going issue through the whole build up! I will probably be spending alot of time on here picking everyones head

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Nine Ball:
<strong>The set that MTI ported for Colonel's next motor flowed over 390 cfm on the intake at his cam lift. Made my 335 cfm LS6 heads look severely dwarfed when comparing area under the curve LOL!

Tony</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">390 cfm <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

 

wallet <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by NataSS Inc:
<strong>They are expensive as hell but speed costs money and I wont deny that for a second. In open road racing you have to have the power to get into the 180+ speed range in our Fbodys. I did the silver state classic challenge last sunday in a 02 C5 and it was flawless at 160mph. But it has a huge aerodynamic advantage over ours. I will have to build the motor to overcome the aerodynamics issues. Right now I am in the process of laying the car out on paper and attacking the individual areas one at a time. But the motor is going to be an on going issue through the whole build up! I will probably be spending alot of time on here picking everyones head</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">NataSS,

I would go ahead and build a high revving solid roller setup with a set of max effort LS6 heads. If you're not afraid to spend mega money, build a C5-R block. This would give you 427 cu in without worries of dropping sleeves or the extra weight of an iron block. This is a proven high endurance race piece that will hold up to the stresses you are describing. An engine of this caliber built properly should take you over 200mph no problem.

Shane

<small>[ May 24, 2002, 11:22 AM: Message edited by: XtraCajunSS ]</small>

 

anyone have a price tag on a C5R block? I have heard 7K+ just for the bare block <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> If thats true its a bit outragous for a bare block

 

http://www.paceparts.com/product.asp?3=22509

 

<img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" /> <img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> Those are just to sexy for words......I need to go be alone for a minute. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by JAS:
<strong>wallet <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Hahaha....I checked mine and didn't see a set in there. <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" />

Those heads are too exspensive to even fantasize about. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

John your the cheapest I've seen those heads for.

John <img border="0" alt="[chug]" title="" src="graemlins/gr_chug.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
When you factor in the cost of the valves, seats, springs, custom Jesel rocker arms ($2500), guides, retainers, etc... you are looking at well over $8K for the heads - without porting! Definitely reserved for the hardcore of the hardcore, too hardcore for me even!
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">That seems to be a bit pricy to me for those heads even as good as they are <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

Heck you can buy some fully assembled Pro Stock heads from Sonny's that will flow 580cfm intake and 400cfm exhaust for just under 10K.

The price to be ls1 top dawg is really starting to climb <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

Although,those heads would be very nice with forced induction with a shortblock built for it.
An easy 1200hp without even trying..
Break out the credit cards! <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Steve

 

If that virgina lottery ticket had panned out I would have some right now. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> Along with a few other high performance toys. <img border="0" alt="[Z06 Corvette]" title="" src="graemlins/z06.gif" /> <img border="0" alt="[pimp]" title="" src="graemlins/gr_pimp.gif" />