We are pleased to announce the release of our second generation Stage 2 2.5L “Long Ratio” Short Block. If you are looking for an engine to road race or run 10 second quarter miles then drive on the street this is it!

The GS650LR exemplifies all of our experience building and tuning high horsepower race and street engines. The GS650L has been installed on daily-driven cars that make over 600HP on the street, safely and reliably. These are the same cars that drive to the track, run sub-11 second times and are driven home. This block is capable of reliably maxing out the GT35R turbo.

The GS650 starts life as a regular STI shortblock. First we replace the weak hyper-cast stock pistons with custom spec forged units (fully race coated). Not only are the pistons significantly stronger than the stock units the pistons are substantially lighter too. The main difference in our motor is the use of the Helix forged H-beam +2mm (Long Ratio) rods held together with ARP L-19 bolts. The longer +2mm rods allow for a more favorable rod ratio that ultimately reduces stresses on the rotating assembly by increasing piston “dwell” time. The end result? An increase in top end power and operating RPM over that of the stock rod length. Very few competitors offer the long-rod ratio engine, and those who do will charge you a premium.

The crankshaft is then modified with our proprietary techniques creating a crankshaft similar to the $2000 STI race crankshaft used on the WRC cars. The bearings are swapped out in favor of Gruppe-S coated race bearings. This addresses all the common main failure points of the stock STI 2.5 engine – spun bearings, cracked pistons, and damaged rods.

The entire assembly is then balanced. Piston walls are bored and honed, all tolerances are triple checked, and the assembly is professionally assembled. The end result is a big power engine that is capable of 8500 RPM operation* and holding 650 crank HP. That’s right, 165 HP PER A CYLINDER. The GS650 is purposely built to tight tolerances for street operation. You will not experience excessive oil consumption and you will not have a rocking issue with our pistons.

FEATURES:

*Gruppe-S / Wiseco Custom Forged Pistons 
*Gruppe-S Detonation Resistant piston coating
*+2mm Long Rod Ratio Design
*Coated High Performance Rod & Crankshaft bearings
*Helix +2mm Forged Connecting Rods with ARP L19 Rodbolts
*Reworked high RPM crankshaft (Nitrided & Cross-Drilled)
*Professionally balanced and assembled
*Capable of up to 650HP Operation
*Final Displacement 2.48L
*Compression ~8.5 : 1

LONG BLOCK FEATURES (Additional):

*Gruppe-S / Cosworth Stage Two camshafts (AVCS available)
*Gruppe-S Stage Two Valve Train
*ARP Head studs & Cometic Gaskets
 

*”Looser” race engines (not recommended for street use) are available – simply let us know if that is what you are looking for.

**8500 RPM requires substantial modifications to the head, oiling system, and other components. We have experience building high revving engines, please contact us for additional details.

Our short blocks features brand new components with the exception of the block halves. The block-halves are sourced directly from Japan. Our block halves are bored and honed for a larger 0.5mm bore which slightly increases compression. The benefits of using used block halves are that they have already been heat cycled and stress relieved (through use), thus eliminating the common failures with brand new un-stress relieved aluminum blocks. If you elect to trade in or have us rebuild your existing block ($500 credit) we will reuse your block halves and crankshaft. The crankshaft will be refinished and balanced as necessary. All other components are brand new.