New LS1 Owners - Newbie Tech - Can anyone confirm this please?




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Thunder55
11-10-2009, 12:34 PM
LQ9
799 heads
Cam
Carb

500HP roughly?


BlackScreaminMachine
11-10-2009, 12:37 PM
Well it all depends. If you select not to have a cam at all, it will make about 250 hp. Camshafts are completely optional in this kind of set up. Thunder Racing Calls it their "Ghost Cam"

lol.

Anyways.

You need more info.

Compression, cam design, and if the heads have been working will all factor in. Also are you asking if this is 500 Fly or Rear wheel? if RW, you need driveline info.

Thunder55
11-10-2009, 01:16 PM
Well I haven't figured the cam out yet, hoping the guru's on here will help me out with that as well.
But all stock heads and short block, just a 750 carb on top and some sort of a cam and yes refering to flywheel HP.


Sales2@Texas-speed
11-10-2009, 02:37 PM
500hp at the crank is not all that difficult to do, even with a very mild camshaft and stock LS6 heads. Yours is the LQ9 flat-top piston, correct (not a dish)? What kind of vehicle is this going into? What supporting mods will you be running?

BlackScreaminMachine
11-10-2009, 02:44 PM
Anything is possible, I just see the compression be a big issue with the cyl head choice. IMO I'd have them milled.

I will refer you to the Dyno section, start searching.

I did some researching and there are some issues.

The LQ9 short block apparently came with high comp pistons which allowed to have a compression ratio of approx 10.1 to 1 BUT the 799 head has a larger Combustion chamber size and if I remember correctly people use these heads as they are akin to a 243 (LS6) head but drops the compression a good amount.

So your going to run into Piston to Valve clearence issues depending on the cam choice (PTV) and also if you mill the head to get the desired compression up to at least 11 to 1 (which helps make N/A power).

I personally would speak to an engine builder since this is not a general 799 head swap on a Fbody 346 short block. Check in the Gen III section. Predetorz or Patrick G should chime in.

BlackScreaminMachine
11-10-2009, 02:47 PM
Also. I did not ask, what is this going in?? I assume a truck or heavier vehicle. If so cam choice may not need to be to crazy, also under curve power maybe more important then top end scream (see Magic Stick ver. 4 or T-Rex).

I see TX speed posted on this so def PM him and see what his thoughts are.

Sales2@Texas-speed
11-10-2009, 03:17 PM
The LQ9 short block apparently came with high comp pistons which allowed to have a compression ratio of approx 10.1 to 1 BUT the 799 head has a larger Combustion chamber size and if I remember correctly people use these heads as they are akin to a 243 (LS6) head but drops the compression a good amount.


That's actually backwards. The 6.0L heads were about 72cc stock, whereas the 243's and 799's were about 64cc so they'll BUMP the compression up!

Thunder55
11-10-2009, 08:05 PM
Thanks for the help guys!

The LQ9 is out of a 2002 Escalade so i am assuming it is the flat top LQ9

I'm putting it in a stripped out 78 Nova, should be in the 2800lbs range I'm guessing.
No supporting mods for the first phase of this build.

First Phase:
LQ9 short block
799 heads
750dp carb
9" rear end with mini spool (not sure on gears)
mildly worked over th350
Thinking 3500 stall ???
and what ever cam you tell me to run :P

BlackScreaminMachine
11-11-2009, 06:24 AM
That's actually backwards. The 6.0L heads were about 72cc stock, whereas the 243's and 799's were about 64cc so they'll BUMP the compression up!

My bad, thanks for the clear up. All these different castings.