Cammed4ever

I took my 862's heads to be ported and polished and this is exactly what they gave me:

The results of port and polish of your LS type cylinder heads for a 2006 Chevy 5.3 4x4 truck are as follows:
Flow bench at 28 in of water depression; before and after modifying the cylinder head.

Lift / Stock Intake / Stock Exhaust / Ported Intake / Ported Exhaust
0.100 62 / 46 / 64 / 51
0.200 126 / 89 / 146 / 98
0.300 187 / 118 / 193 / 131
0.400 214 / 146 / 223 / 155
0.500 223 / 171 / 245 / 178
0.600 227 / 186 / 254 / 201
Exhaust / 72.5% / 72.85%
to intake
Average

Note: That while flow at every valve lift increased over stock, the average exhaust to intake flow ratio did not change. Increasing the LS1 heads flow ration in this respect is detrimental to performance and actually hurts low-end throttle response. GM did it right when they designed these heads for the street.
P.S The springs we just installed in your heads are a lot stronger than the stock springs you need to do some stock modifications: Aftermarket Studs.


THIS IS THE SHEET THAT THE SHOP GAVE ME, WHAT DO YOU GUYS THINK? IS IT DONE RIGHT?
PLEASE LET ME KNOW WHAT YOU THINK CAUSE I DONT KNOW MUCH ABOUT HEADS NUMBERS.
WAS IT WORTH IT TO GET THEM WORKED? ($660)
AND THE MOST IMPORTANT QUESTION, WOULD I IMPROVE IF I SWITCH TO 243'S???

THANKS AND SORRY FOR THE LONG POST, JUST WANTED TO ADD ALL THE DETAILS THEY GAVE ME.

batboy

iTrader: (6)

Stock 243 Head Flow Numbers
Chamber 64.45 cc-------0.100---0.200--0.300--0.400---0.500---0.550---0.600
Intake 210 cc-------------62------126-----184----224------251-----256-----257
Exhaust 75 cc-------------57------108-----143----163------176-----180-----183

Nothing to gain by switching to stock 243, but if the 243 heads were ported and milled, then sure you would gain some power. The question is it worth the extra cost?

Cammed4ever

So, should I just trow a TBSS intake and a bigger TB than my stock to improve??
I think my intake and tb are killing me..

1FastBrick

iTrader: (17)

IMO you should have sent them out to one of our sponsors like WCCH or SDPC and had a stage2 cnc job done. There is probably 20-30 cfm left on the table. If just the porting was that much, you could have gotten the cnc work done for 500-600.

Mikey 97Z M6

iTrader: (35)

Sad to say but I would have expected a lot better flow for what they charged you. Even with stock sized valves I would have expected mid 270's from a full port and for that kind of money spent.

Mike

Cammed4ever

Yup, thats why I posted those numbers cause I didnt think they where ported enough..
Sad sad.. They where ported, polished, and 3 angle valve job but still too much $ for what i got

craigsix

i dont think you were over charged especially if they milled the heads also.

Cammed4ever

They said they "shaved" them, i dont know if by that they mean "milled"

batboy

iTrader: (6)

Mill, shave, cut... it all means the same thing. If that price includes a complete valve job, milling, and porting... then you probably got your money's worth.