chevybayboy

iTrader: (6)

How much more do the ls6 heads flow over Ls1... I put my ls6 head next to my Ls1 and it seems intake and exaust holes are the same size?? So whats the diff.??

sjsingle1

iTrader: (1)

many many differences..........the LS6 exhaust ports are D shaped for 1............

FASTFATBOY

iTrader: (23)

LOL, about 40 hp.

chevybayboy

iTrader: (6)

Really 40 HP? Ok... Well looks like ill be porting my ls6 heads while there off

FASTFATBOY

iTrader: (23)

Ls1 makes about 300 to the wheels

Ls6 about 360 to the wheels.

Heads are at least 35hp of that number.

Felix C

BS & more BS.

Correct answer: 10% more flow per every chart I have seen here.

chevybayboy

iTrader: (6)

10% how many more pony power would that be over stock

FASTFATBOY

iTrader: (23)

Ok, so where does the power difference come from LS1 vs LS6?

My stock LS6 makes 385 to the wheels with mild bolt ons and exhaust through a six speed.

Both stick cars:

LS1 300 to the wheels

LS6 355 or so to the wheels

55RWhp difference, which is about 80 at the flywheel.


Auto car:
https://ls1tech.com/forums/dynamomet...only-dyno.html

Pat G says about 25rwhp, about 35 ish at the flywheel.
https://ls1tech.com/forums/dynamomet...-increase.html

If you take the time to do a GOOD valvejob and mill the heads to get 11 to 1 compression even more power is there.

Felix C

Question was about flow nos. Nothing more. Actual answer in terms of gain on a stock LS1 is 15rwhp.

Whatever personal experience you provided is from an LS6 engine. Entire package.

FASTFATBOY

iTrader: (23)

Your the man, carry on.

Felix C

Cold hard facts. That is all.

chevybayboy

iTrader: (6)

Thanks both you guys for info all I can get helps

chevybayboy

iTrader: (6)

So will,porting and polishing my heads change my compression? If so lower or higher

Theblacknightls1

iTrader: (1)

Ls1 heads 230 cfm ls6 260 cfm. Correct me if I'm wrong.

Theblacknightls1

iTrader: (1)

No. Porting will increase flow. Milling the heads will increase compression.

chevybayboy

iTrader: (6)

Ok cool thanks

Mike Morris

iTrader: (55)

Some good info here to read...

http://www.c5registry.com/documents/ls6/page2.htm

chevybayboy

iTrader: (6)

That was def. A nice piece of info

crainholio

iTrader: (2)

Any metal you remove from the combustion chambers will lower the compression ratio. Easy to get it back with milling, though.

Be aware it's very easy to create imbalances in airflow if you get crazy with the hand-porting. I only recommend polishing to remove the casting roughness in the ports for non-professionals (like myself). And flush 'n brush them thoroughly afterward to get all the abrasives and aluminum dust completely gone.

Leave the carbide burr to the pros who know what they're doing and can get all 16 ports to reasonably symmetrical volumes and airflows.

Keith_Shapiro

iTrader: (1)

I'll tell you soon I just took my 806 heads off today and the 243's gone in this week