black_c7

solotronics

where did you get everything cryoed? I have been doing research and want to cryo my valve train when I put in ported heads and cam.

sr71bb

On a maximum effort LT4 which I will define as 1400 RWHP and above, you will need all billet internals, a thicker than stock block sleeves that is also oringed, a improved valve train setup such as Manton Pushrods setup; solid roller cam, great flowing heads and intake such as LME billet. This will live in an 8000 RPM environment with over 35 pounds of boost. An example of that combination can be found in the fastest all boost C7 LT4's on the planet which currently are AMP prepared C7's (their shop car and their customers white C7 convertible).

The amount of money to make a LT4 set up to reliably live at the 1400-1500+ level compared to the 1200-1300 level is SUBSTANTIAL. The stock sleeved block for example will not live long past the 1200 RWHP level. Not to mention the cost of associated components that are required to support 1400-1500+ RWHP. A8 trannies for example cant live reliably in this range nor can the stock differentials. You will also need custom made components such as intercoolers, improved crankcase pressure components, improved suspension components, multiple blowoff valves, wider blower belt setups such as 10RIB, 15 inch tire and wheel setup, yada yada yada

MOST importantly you need a GREAT tuner. It is easy enough to duplicate a hardware setup if you throw enough money at it but you wont get the results you want without a great tuner. He can make all this LIVE .

Earl H

This is an interesting thread. I'm not sure that there is a "for sure" answer to the OP's question as there are a number of hi-hp lt4 C7's that have lived under extreme power pushing 8's at the track for 2 to 3 dozen passes and street miles and there are some that are grenading fully built motors. My own personal/company single turbo Z06 pushed 1250whp on the SBE. I got a little nervous and didn't want to go higher, so I cut things off. The dyno session was backed up with an mid 8 sec pass with only 3 track hits at 5#'s shy of where I stopped on the dyno. The car is running without a hitch...at the moment. The shop that worked with me to build the car had close to if not over 2 to 3 dozen 8 sec passes on their own shop car and was running great when they decided to put in a strengthened shortblock. Contrast that with a shop that I know of that has blown up sleeved LT4's running 2/3's the power level. Hell, I've seen some guys killing motors with the stock blower. Everybody has "their" guy working on their car. This is where things get touchy as there are a number of "My Guy"'s that have left a trail of broken parts as they learn or push things and THOSE stories become the prevailing wisdom on the topic.

I am looking to turn things up a bit in 2019 on my Single Turbo setup. After spending stupid money on building an ERL block/Mast headed Gen V CTS-V engine, only to have it taken out by a valve, I wanted to be $$ smart and spoke with a few good PURE engine builders about LT4 options. I can source my own parts, so these guys had nothing to gain by "upselling" me. In short, the stock the SBE, in the right hands, can take a considerable amount of punishment. The basic foundation of the LT4 is pretty strong. Weakpoints when you start exceeding 1200whp (and really using that power), from the guys that I have talked to: pistons/wring gap, stock sleeved block (as things are turned up) and then rods (will depend greatly on your choice of FI..Spray, PD Blower, Centri Blower, Turbo,, etc). I have identified a pretty cost-effective and robust shortblock package, that I am pretty close to pulling the trigger on and testing it this year.

Now, this is only one view point...and there will be many out there. However, this viewpoint is based on what I have experienced: both good and bad with my 2 rolling "test-beds"