Max compression lq4
10-22-2016, 05:58 AM
#1
TECH Apprentice
Thread Starter
Max compression lq4 So this is my first ls motor build. I am looking to order a stroker 408 kit. I took the block to the machine shop to get it bored but they said they want the pistons. So it's time to order.
Motor will be a race only nitrous motor. I would love to spray the snot out of
I enjoy the bracket stuff 9 second class and occasionally run at heads up so wanting to go 8.50 at that class.
So looking for 13.1. I have 799 CNC 64 on the chamber's milled.010.
Would +5 get me there and what are the chances I'll hit the heads with a dome.
Maybe a 370 would be a better route? Any experienced advice would be appreciated
Motor will be a race only nitrous motor. I would love to spray the snot out of
I enjoy the bracket stuff 9 second class and occasionally run at heads up so wanting to go 8.50 at that class.
So looking for 13.1. I have 799 CNC 64 on the chamber's milled.010.
Would +5 get me there and what are the chances I'll hit the heads with a dome.
Maybe a 370 would be a better route? Any experienced advice would be appreciated
10-22-2016, 07:16 AM
#2
FormerVendor
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Piston/Head CMM Today, the "custom " piston manufactures can CMM the head, at no extra cost.
This would allow for exact measurement of a combustion chamber.
Then the piston crown can be correct, the inverse, of the head by the use of that CNC file.
My requirement was for Pikes Peak racing, MacPherson's race engine
(17-1 CR).
NOW, for a lot of NOS, use the IGN-1A coil (280mj) eight of them.
The Spark Plug Autolite 3932x-3922x or lower heat range NASCAR Racing Plug will work much better.
The crankshaft should be fit with the 60-2 (GM58x) high resolution Target Wheeel NEEDED for an accurate Spark Instant.
Will you use Dry/Wet NOS ?
Lance (*!*)
This would allow for exact measurement of a combustion chamber.
Then the piston crown can be correct, the inverse, of the head by the use of that CNC file.
My requirement was for Pikes Peak racing, MacPherson's race engine
(17-1 CR).
NOW, for a lot of NOS, use the IGN-1A coil (280mj) eight of them.
The Spark Plug Autolite 3932x-3922x or lower heat range NASCAR Racing Plug will work much better.
The crankshaft should be fit with the 60-2 (GM58x) high resolution Target Wheeel NEEDED for an accurate Spark Instant.
Will you use Dry/Wet NOS ?
Lance (*!*)
10-22-2016, 05:11 PM
#4
FormerVendor
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NOS Coil Dwell OK, use the Holley "smart coil " (IGN-1A) required for NHRA Pro-Stock.
Then specify the 58x (60-2) crankshaft target wheel.
Run a coil dwell of 3.0ms N/A, then ramp up to 6ms coil dwell on NOS.
I would also use the FireCore 250 wires.
Lance
Then specify the 58x (60-2) crankshaft target wheel.
Run a coil dwell of 3.0ms N/A, then ramp up to 6ms coil dwell on NOS.
I would also use the FireCore 250 wires.
Lance
10-24-2016, 10:00 AM
#7
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NOS Engine Strength YES, My Guess is about 12:1 though anyone would ask for head CCs, deck (+.007 with GM MLS), piston valve notch CC, etc ?
I use EAP by Performance Trends for engine model questions, most often done for free to verify business safety.
There are TWO common LS-1 chamber contours used by piston manufactures, one can hit the head@+.007" deck.
REMEMBER a +5cc piston with dome is +9cc dome WHEN the two valve notches of 4cc are considered (9-4=5).
Lance
I use EAP by Performance Trends for engine model questions, most often done for free to verify business safety.
There are TWO common LS-1 chamber contours used by piston manufactures, one can hit the head@+.007" deck.
REMEMBER a +5cc piston with dome is +9cc dome WHEN the two valve notches of 4cc are considered (9-4=5).
Lance