Building Road Race LS6
Building Road Race LS6 In the middle of building, or rebuilding my LS6 motor. I'll talk to the machinist for all full specs and measurements tomorrow. Aiming for 12.1-3:1 compression ratio. The motor will see mostly street but is being built for future high revving trips to the road course with great mid range power coming out of the corner and more top end then you'll see in the straight. Should be fun. Here's how its coming along so far, tell me what you think:
Fast 90mm & LS2 TB both ported
Bosch 40lb fuel injectors
TFS 215cc heads milled to 60cc
Cometics 0.040 mls head gasket
Patriot Extreme Valve Springs, shimmed
Comp Cams custom grind 236/243 112lsa +4 degrees advanced
597/610 lift @ 0.50 (around there, waiting on cam and specs card)
JE forged domed pistons, 6+/-cc's (waiting on all measurements)
JE forged lightweight I beam connecting rod
stock micro polished crank
cleaned and bored LS6 block, still 346ci
Fast 90mm & LS2 TB both ported
Bosch 40lb fuel injectors
TFS 215cc heads milled to 60cc
Cometics 0.040 mls head gasket
Patriot Extreme Valve Springs, shimmed
Comp Cams custom grind 236/243 112lsa +4 degrees advanced
597/610 lift @ 0.50 (around there, waiting on cam and specs card)
JE forged domed pistons, 6+/-cc's (waiting on all measurements)
JE forged lightweight I beam connecting rod
stock micro polished crank
cleaned and bored LS6 block, still 346ci
TECH Regular
Joined: Oct 2007
Posts: 433
Likes: 0
From: Gillette, WY
I'm also interested in this setup. What you are going for here is almost exactly what I would like to do in the future with my CTS-V. I use the car mostly on the street with the occasional track day (3-4 times/year in a perfect world). The way I see it, forced induction is not an option for track day use, so built motor with H/C/I is the best route, which you obviously agree with. Keep us posted on your progress and how this beast turns out.
TECH Regular
Joined: Mar 2006
Posts: 471
Likes: 0
From: Rolesville, NC
high Reeving high compression for track days ?
I would go with a smaller cam for more immediate throttle response, ie out of the corner and UP to speed. Bigger cams are cool but dont come on until 3000 rpms. most corners are 2200-2500 rpms then up to redline in 3rd and 4th gears. Seldom 2nd gear
guys that have 7000+ rpm motors wind up doing lots and lots of valve work all the time.
stick with a 6600 red line, and shift at 6500. Rember the LS6 and Fast intakes were designed to work at this level, max hp at 6400 and max torque at 4800.
stick with 11.1 compression to use pump gas 93 octane
dont forget cooling. Bigger radiator, plus oil cooler and accusump too keep the engine alive.
Good Luck
I would go with a smaller cam for more immediate throttle response, ie out of the corner and UP to speed. Bigger cams are cool but dont come on until 3000 rpms. most corners are 2200-2500 rpms then up to redline in 3rd and 4th gears. Seldom 2nd gear
guys that have 7000+ rpm motors wind up doing lots and lots of valve work all the time.
stick with a 6600 red line, and shift at 6500. Rember the LS6 and Fast intakes were designed to work at this level, max hp at 6400 and max torque at 4800.
stick with 11.1 compression to use pump gas 93 octane
dont forget cooling. Bigger radiator, plus oil cooler and accusump too keep the engine alive.
Good Luck
