The higher pressure pump and the injectors appear to exist already judging by the spy photos of the next Z06. The pump would be the same.

 

Early tech info on the LT1 suggested that the piston shape was designed to compliment the head shape for ideal mixing, any concerns with changing it?

Valve covers are for the PVC system to better scavenge oil.

Cool stuff Texas Speed, thanks for sharing with us! Looking forward to seeing what a slightly larger cam can do!

 

Ok question here.

On the new fuel system how do they control the pressure? If the pump is running based on the engine speed there should be some kind of recycle valve to control the pressure (similar to any positive displacement pump) I dont see the one in that photo of the fuel system.

I would be interested to know how this works, because this would be a large determiner in what the fuel delivery capacity is.

 

So does the LT1 have reverse-flow cooling (cools the heads first) or have they moved the t-stat to the outlet side now? Trying to map out the flow with this new water pump.


Comparing to my C5 motor the t-stat housing is smaller which leads me to believe it's the outlet now.

 

The outlet looks like it is on the top now. GMs LT1s in the 90s had reverse flow, which added about 20hp. MOPAR did it in their 60s with their wedge heads. They had external steam tubing and the reservoir/recovery bottle played an integral part in sublimation. Also, they were iron blocks. The new LT1 has block first cooling.

 

That didn't take long! My cars block was shipped from TS way back when my car was a youngy!

 

Subscribed... Good info. great job Texas Speed

 

Being a gear head, I'm LOVING reading all of this and seeing the photos. SO exciting when a brand new GM V8 generation shows up! The RTV concerns me, not just for the clean up, but for leaks. The LT1 from 92-97 leaked oil badly down the back of the engine from the intake manifold. The robot that put the RTV beed on the back of the intake where it touched the block could not get up against the oil pressure sending unit (if I'm remember that correctly), and oil would leak out there. I just think this is a bad move by GM. It will be interesting to see if they stick with it.....

 

 

Guys sorry I'm slow getting to respond. I'm working 1000% right now trying to get everything we can up & running for the LT1! CNC Heads, bunches of different camshafts & even headers are all going at the same time.......

 

Weird. GM's Service information states the crank is forged.

Here is a copy and paste...


Engine Component Description
The 6.2 Liter V8 LT1 Engine


Camshaft and Drive System

A billet steel 1-piece camshaft is supported by 5 bearings pressed into the engine block. The camshaft has a tri-lobe forward of the rear journal for actuating the direct injection fuel pump. The CMP actuator is mounted to the front of the camshaft and retained by the CMP solenoid valve. The CMP actuator is driven by the crankshaft sprocket through the camshaft timing chain. The CMP sensor wheel is incorporated into the front face of the CMP actuator with the CMP sensor and CMP actuator magnet mounted in the engine front cover. A timing chain tensioner is mounted to the front of the engine block above the crankshaft sprocket. The externally splined crankshaft sprocket is positioned to the crankshaft by a key and keyway. The crankshaft sprocket external splines drive the oil pump drive gear. A retaining plate mounted to the front of the engine block maintains camshaft location. Refer to Camshaft Position Actuator and Solenoid Valve Description.

Crankshaft

The crankshaft is made of hardened forged steel. The crankshaft is supported by 5 crankshaft bearings. The bearings are retained by crankshaft bearing caps which are machined with the engine block for proper alignment and clearance. The crankshaft journals are undercut and rolled. The center main journal is the thrust journal. A CKP reluctor ring is press-fit mounted at the rear of the crankshaft. The reluctor ring is not serviceable separately.

Cylinder Heads

The cylinder heads are cast aluminum and have pressed in place powdered metal valve guides and valve seats. The valve rocker arm covers are retained to the cylinder head by 10 perimeter mounted rocker arm cover bolts. Cylinder heads are a high-flow design with offset intake valve rocker arms.

Engine Block

The engine block is a cam-in-block deep skirt 90 degree V-configuration with 5 crankshaft bearing caps. The engine block is cast aluminum. The 5 crankshaft bearing caps each have 4 vertical M10 and 2 horizontal M8 mounting bolts. The camshaft is supported by 5 camshaft bearings pressed into the block. The left bank of cylinders are number 1-3-5-7 (#1 is front left) and the right bank of cylinders are 2-4-6-8 (#2 is front right) viewed from the flywheel end of the engine. The engine firing order is 1-8-7-2-6-5-4-3.

Exhaust Manifolds

The exhaust manifolds are a 1-piece cast iron design. The exhaust manifolds direct exhaust gasses from the combustion chambers to the exhaust system. Each manifold also has an externally mounted heat shield that is retained by bolts.

Intake Manifold

The intake manifold is a 1-piece composite design that incorporates brass threaded inserts for mounting the throttle body, and wire harness studs. Each side of the intake manifold is sealed to the cylinder head by 8 silicone push in place gaskets. The electronically actuated throttle body bolts to the front of the intake manifold. The throttle body is sealed by a 1-piece push in place silicone gasket. The intake manifold covers the direct injected fuel rail assembly, fuel pipes and fuel pump. The manifold absolute pressure (MAP) sensor is installed and retained to the top left of the intake manifold midway back under the left engine cover. The evaporative (EVAP) emission canister purge solenoid valve is mounted right front of the intake aft of the throttle body assembly

Fuel System

The fuel system consists of 8 separate direct injection fuel injectors, two high pressure fuel rails, a high pressure cross-over fuel pipe (connects the two fuel rails), a high pressure fuel feed pipe (connects the cross-over pipe to the high pressure fuel pump), a high pressure fuel pump and a low pressure fuel feed pipe. The injectors are each seated into their individual bores in the cylinder heads with two combustion seals to provide sealing. The high pressure fuel pump mounts to the rear of the Valve Lifter Oil Manifold in the engine valley. Motion is transmitted to the pump from a tri-lobe on the rear of the camshaft through a hydraulic roller lifter.

Oil Pan

The structural rear-sump oil pan is cast aluminum. Incorporated into the design is the oil filter mounting boss, drain plug opening, baffle, oil deflector, oil pump screen, and oil level sensor (wet sump system only). The oil filter bypass valve is in the oil filter assembly. An external oil cooler assembly is mounted directly to the left side of the oil pan. The oil pan is sealed to the oil pump with a silicone push in place gasket and to the engine block with RTV sealant. Dowels are pressed into the pan for aid in alignment to the engine block during assembly.

Piston and Connecting Rod Assembly

The pistons are cast aluminum. The pistons use 2 compression rings and 1 oil control ring assembly. The piston is a low friction, lightweight design with a recessed top and barrel shaped skirt. The piston pins are chromium steel and are a full-floating design. The connecting rods are powdered metal. The connecting rods are fractured at the connecting rod journal and then machined for the proper clearance. All applications use a piston with a graphite coated skirt. The piston and pin are to be serviced as an assembly.

Valve Rocker Arm Cover Assemblies

The valve rocker arm covers are cast aluminum and use a pre-molded silicon gasket for sealing. Mounted to each rocker cover are the coil assemblies. Incorporated into the left and right valve rocker arm covers are the positive crankcase ventilation (PCV) fresh air passages. Incorporated into the left cover is the oil fill tube (wet sump system only).

Valve TrainMotion is transmitted from the camshaft through the hydraulic roller valve lifters and tubular pushrods to the roller type rocker arms. The nylon valve lifter guides position and retain the valve lifters. The valve rocker arms are mounted on individual pedestals or pivot supports that are incorporated into the cylinder heads. Each rocker arm is retained by a bolt. Valve lash is net build. Cylinders 1, 4, 6, and 7 are active fuel management. Refer to Cylinder Deactivation (Active Fuel Management) System Description.

 

Great stuff Trevor. I love ripping stuff apart, just to see what makes it tick.

Can't wait to see the mods!

 

How do you think the motor will handle boost in it's stock form? Also do you forsee any problems running e85 on the stock fuel system. Like rubber or other items in the system that will break down over time?

 

subscribed

 

Our engine dyno testing has commenced, and we will be testing multiple cams, as well as our PRC ported cylinder heads, late today! All of our testing is done on our engine dyno before we ever put it in a car. We are testing proprietary lobes that are not "off-the-shelf" grinds, and we are also testing the limits on the cams relative to piston-to-valve clearance. We do extensive testing BEFORE it ever makes it into a car. This provides us with exact numbers for our customers to compare our various camshafts, cylinder heads, etc. We want to know what each part makes and then put it all together. You can't continue to improve on a part if you aren't testing it individually! Everyone will be very pleased with the results.

Stay tuned for lots of information and videos!

 

We will not be changing the combustion chamber on our PRC ported LT1 cylinder heads. This is not only for the reason you mentioned but also for keeping the compression ratio up.

We will be posting lots of camshaft and cylinder head engine dyno information very soon!

 

Here is the baseline with stock internals. 518 HP and 510 TQ! Keep in mind this is without cats or front drive accessories. We will be testing our proprietary camshafts this afternoon, then onto PRC cylinder heads!