Can you post these again please? Thanks!

 

<BLOCKQUOTE>code:<HR><PRE>Without Manifolds - Headflow Only:

Cylinder Head Intake Manifold .200" .300" .350" .400" .450" .500" .550" .600"

Stock LS1 N/A 137 187 207 223 228 237 242 243
Stock LS6 N/A 156 204 225 243 257 268 275 278
Ported LS1* N/A 144 200 225 245 261 272 283 292
Ported LS1** N/A 164 217 234 253 270 284 296 305
Ported LS6 N/A 159 212 236 255 272 300 307 314


With Manifolds:

Cylinder Head Intake Manifold .200" .300" .350" .400" .450" .500" .550" .600"
Stock LS1 LS1 136 184 200 214 222 227 229 235
Stock LS1 LS6 136 186 206 223 227 236 241 242
Stock LS6 LS1 156 199 212 224 232 238 243 247
Stock LS6 LS6 154 204 220 235 247 257 263 265
Ported LS1** LS1 141 185 205 222 232 241 251 258
Ported LS1** Truck 163 206 224 237 249 262 265 270
Ported LS1** LS6 166 211 229 244 257 269 277 283
Ported LS6 LS1 156 199 217 230 242 253 263 268
Ported LS6 LS6 153 202 222 241 257 270 280 289</PRE>[/QUOTE]

* Original Stage II heads from New Dog, Old Tricks; GMHTP May/July 2000

** Latest revision.

Info originally from Chris Endres

 

Why should a ported LS6 head do better than a ported LS1 head on the intake side?

What about exhaust numbers stock and ported?

 

Dennis, Looking at these side views of the LS6 intake port (left) and the LS1 intake port, it’s very easy to see the difference in the port floors and the short-turn radii.



A vertical view of the same two intakes shows the LS6 (left) has a port that is taller at the entrance but wider in the mid-section, thus preserving cross-sectional area. The LS1 port does not share that characteristic.



Side view cuts of the LS6 (left) and LS1 exhaust ports, again, show a smoother short-turn radius. On the piece at left you can also see some of the change to the combustion chamber. Note how the chamber wall in around the spark plug has been moved in, towards the valves and the roof has been lowered.

 

kewlbrz, you have my greatest respect in terms of your knowledge. Where do you find all this info? I'd love to be able to be on top of everything like you are. Share the resources brotha'! :D

 

C5noir, Those pics are from GM, and were included in the Hib Halverson Article on the differences between the LS1 and LS6.

:cheers:

 

Looks like as we go further in flow numbers, no improvments will be achieved since the intake manifold will be a major restriction.

So how much rwhp would the LS6-LS6 combo gain over LS1-LS6 ?