Unplanned Engine Drama
Since the beginning of the Ultima desire I’ve wanted to put in the LS7 as it’s heart. The iconic engine just felt like the right beast for the car instead of newer engine architectures. However that plan was unexpectedly tossed into chaos with GM’s announcement to discontinue production.
Sadness….
Summit Racing is out
Everywhere I looked it seemed they were already gone by Sunday. Jegs, Speedway, etc. All dried up.
Finally found one at BoostDistrict.com
I found what could be the last one out in the wild. During the excitement I accidentally ordered the base LS7 (no longer in production months ago) from them, but after a few phone calls confirming they have the 570 HP version I was able to straighten out the order. It should be on its way soon. Just many months early, since I don’t have the chassis yet. That is planned for shipment in March sometime.
LS427/570 Chevrolet Performance Crate Engine Fast Facts
A new wet sump oiling system facilitated easier and less costly installation, because the remote oil-tank reservoir for the production-based LS7's dry-sump system was not required. The engine was equipped with the popular F-car wet sump oil pan and accompanying LS3 oil pump. The aggressive camshaft calibration in this engine requires the use of LS427/570 Engine Controller and Harness Kit p/n 19420000 (sold separately). Chevrolet Performance recommends 15W50 Mobil 1 engine oil for the LS427/570 engine.
LS427/570 Tech Specs
Part Number: 19421004
Engine Type: LS-series small-block V-8
Displacement: 427ci (7.0 liters)
Bore x Stroke: 4.125 x 4.000 inches (101.6 x 92 mm)
Block (P/N 12602689): cast aluminum block with 6-bolt, cross-bolted main caps
Crankshaft (P/N 12611649): forged steel
Connecting Rods (P/N 12661677): forged titanium
Pistons: hypereutectic aluminum
Camshaft Type (P/N 19419859): hydraulic roller
Valve Lift (in): .591 intake/.590 exhaust
Camshaft Duration (@.050 in): 227 degrees intake/242 degrees exhaust
Camshaft Lobe Separation Angle: 116 degrees
Cylinder Heads: CNC-ported LS7-style ports with 70cc combustion chambers
Valve Size: 2.200-inch titanium intake, 1.610-inch sodium-filled exhaust
Compression Ratio: 11.0:1
Rocker Arms: investment-cast, roller-bearing trunnion
Rocker Arm Ratio: 1.8:1 (offset intake)
Recommended Fuel: premium pump
Maximum Recommended rpm: 7,000 rpm
Balancing: internal
I plan on replacing the wet sump pan with one from Armstrong Race Engineering (ARE) full dry sump system, so not too concerned with its current setup. Looking forward to this unplanned purchase!
