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I've been documenting my HPR 468 build on another forum that a number of you frequent, but for those who don't visit the CF board, I'll duplicate what I've posted over there and place it here.
For those who don't know, I'm having a 468 stroker built off my original LS7 block, and topping it off with a set of WCCH based Brodix BR7 BS275 heads with Crower shaft rockers.
The cam is a custom spec hydraulic designed by Eric and Billy Godbold from Comp cams.
We will be testing a few different intakes on it, including my original Mamo ported MSD, the Holley Hi-Ram, the new FAST plastic Hi-Ram, and possibly a Shearer dual plenum Hi-Ram hybrid.
The motor is nearing completion and will be heading to an engine dyno for break-in and manifold testing. Once completed, it will be heading for the engine bay of my C6 Z06, which runs a ZR1 spec TR6060 (MH3 gearing) and 3.90 rear gears.
Current race weight for drag racing purposes is 2950 with 1/4 tank of fuel, but hoping to get close to high 2800's once I've completed the additional work on my interior.
waiting 4 which intakes sucks the most air and provides the cfm needed for the stroke and heads combination. You gonna have tq regardless. All i ask is rpm peak and compression and i'll have general idea.
After much deliberation, Erik and Billy Godbold came up with a custom spec hydraulic roller using some special lobe designs to complement the Brodix top end and the desired power band.
I run this car in all types of competition, 1/4, 1/2, 1 mile (and longer), HPDE's, etc........basically a heavy hitting street car that can perform at all levels, not just a one trick pony Camshaft arrived, installed, and degreed at 108 intake center line
I was originally going to go with an All Pro setup on this setup but decided against running a solid roller for easier maintenance schedules of the hydraulic cam.
Getting together with Richard at WCCH, he ported up a set of Brodix BR7 BS275 heads, with a full on Crower shaft rocker setup with all options. They are also equipped with oversized 2.250" titanium intake valves and inconel 1.615 exhaust.
We had additional machine work done to gives us additional clearance to run custom double taper 7/16 pushrods.
With my custom piston setup, we came up with a final combustion chamber size of 65cc to get my desired 13:1 static compression, using a Cometic .051 .
I wanted to run the new Comp conical springs but unfortunately we couldn't source any spring locators that worked with the smaller LS guide diameters (the springs were designed for a bbc).
We fell back on the PAC 1209X springs to handle the valve train, where I'm expecting to spin the motor to around 7700 RPM (peak power expected to come in around 7000-7200).
Johnson short travel ST2126LSR lifters complete the valve train.
Decided to replace my standard ATI dampner with a 10% under driven version.
Matched with my new EWP, ProSpeed dual spal fan and shroud, and DeWitts radiator, I hope to free up a few ponies while also keeping the car cool when sitting in the extreme hot weather we get in the desert southwest.
I'll be using the Comp LS tall valve covers with integrated spring oil cooling, along with the LSX Concepts lifter valley cover with a single oil feed line off the oil pressure sensor.
waiting 4 which intakes sucks the most air and provides the cfm needed for the stroke and heads combination. You gonna have tq regardless. All i ask is rpm peak and compression and i'll have general idea.
We've got a few things we will be testing on the engine dyno, including throttle bodies larger than the NW102.
I'm 13:1 static compression, running on E54 (AZ version of E85).
My head flow numbers were tested following all the work I had Richard...tested on his flow bench.
See below....
Awesome Build
Following here as well!
My Prognostication is the new Fast Hi-Ram will make the most Peak,
MMS MSD Highest Average.
Thanks, bud.
I was getting some grief for not posting my build on all the forums I belong too....... way too much time and work to do that LOL.
Keep in mind that the new FAST has a long runner option too, so if I desired to do so, I suspect I could out power the MSD at any RPM range I chose using the appropriate runner for that chosen power band.
With the cam I'll be running, the MSD would act as a restrictor plate, as witnessed on Jeremy's setup....peak power capped just under 6400 RPM.
The thought is the mid length runner trumpet will be the hot ticket for me...... the short runner would have it peaking in excess of 7500. Mid length we're calculating close to 6900-7000, which should just about be perfect while keeping torque up across the board.
The engine dyno test should be very telling
Thanks, bud.
I was getting some grief for not posting my build on all the forums I belong too....... way too much time and work to do that LOL.
Keep in mind that the new FAST has a long runner option too, so if I desired to do so, I suspect I could out power the MSD at any RPM range I chose using the appropriate runner for that chosen power band.
With the cam I'll be running, the MSD would act as a restrictor plate, as witnessed on Jeremy's setup....peak power capped just under 6400 RPM.
The thought is the mid length runner trumpet will be the hot ticket for me...... the short runner would have it peaking in excess of 7500. Mid length we're calculating close to 6900-7000, which should just about be perfect while keeping torque up across the board.
The engine dyno test should be very telling
Fast and MSD will be very flat up top. I ran into this with my LS3 from 66-7600 using the mid runners. I gained 46RWHP by swapping on the X1 intake (same day same dyno no tune change) This motor will likely perform much better with the larger plenum intake. Good luck and can't wait to see results.
Nice build...where is the engine getting dyno'd? Wish i could seemy Performance Design crossram ls7 mani get tested on that combination. Its going on my RHS 427, but nothing to compare it to
Nice build...where is the engine getting dyno'd? Wish i could seemy Performance Design crossram ls7 mani get tested on that combination. Its going on my RHS 427, but nothing to compare it to
LG just recently installed and tested one on a client's LS7 .....
This is going to be a bad *** build! I wish I could have gone this route vs a 427
We're all pretty optimistic that she'll put down some serious power.....if we can get the airflow up top to feed the cylinders.
The NW102 created a vacuum in the intake at WOT on other 468 builds with a smaller cam and head package with 1 7/8th headers.
04-15-2019, 10:42 AM
My HorsePower Research HPR 468 build 
