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(Picked up off another forum)

The flow sheets for some of the new hemi heads:

This bench is in Houston and for some reason the benches in Houston run a bit high (altitude, Humidity) I'm not sure. I know David Vizard got 270 CFM max on the 5.7 hemi and our max numbers were 283 CFM so that is why some of the numbers I have quoted on this page are different from what I have below. I was correcting the a bit because I know these numbers are a little higher than most benches will get about 5% more. But these are the actual numbers we got. These are without a flow tube on the exhaust so the exhaust numbers are a bit lower

5.7 Hemi Stock 6.1 Stock 6.1 pocket port
Int/Exh Int/Exh Int/Exh
0.100" 75/41 85/42 77/46


0.200" 169/107 174/111 170/115
0.300" 241/146 246/160 253/164
0.400" 273/163 290/179 304/187
0.500" 281/169 310/179 336/190
0.600" 286/172 318/179 359/194
As you can see the exhaust stalls out after 0.400" but without a flow tube that may not actually be that bad.

5.7L uses a 2.00 Intake valve, while the 6.1L uses a 2.08 Intake
Thought everyone would find this information useful.
 

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Man, I've been away from engine modding for too long.... that was greek to me for 10 seconds ;)

Are these current OEM heads, or production aftermarket? If we can get a programmer, or better a MAF conversion with better flowing heads or port/polished OEM heads and revised intake, the 5.7L should be able to pick up over 50HP easily with headers, the 6.1L should be through the roof.
Any spys at Chrysler engineering reading this, send a bootleg copy of the CANBUS code map and any other help to the aftermarket now!! Big$$$$ and you can remain anonymous...... ( just kidding :fingersx: , I don't advocate piracy or condone illegal acts)
 

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correct me if I am wrong but none of these engine upgrades would work unless we can change the computer parameters right?

Such as 6.1 heads on 5.7, cams, intakes and so forth. Would the engine actually starve for fuel and not run at all?
 
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