Subject says it all. it has to be a LN2 because of class rules. but its for circle track. ive spent most of the day reading and planning and have a pretty decent plan but i am curious what people have done or would recommend. ive build a bunch of ford motors but this is my first GM motor. i know about pushrods and valve train geometry. from what ive learned today the LN2 isnt that supported by the aftermarket community. so currently im looking at molnar rods and wiseco pistons. and cams from CCW. 1.6 rocker upgrade. balance shaft delete. i read mention of someone using ecotec pistons in an LN2? but i cant seem to find that post again. i normally go for long rod builds but have only been able to find 5.590" rods for this particular build, excluding the light weight ones that need to have the crank ground. I admit that i am not the know all end all and im very interested in learning about this motor and this build. Thanks Ben.

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Benjamin Ashford wrote:Subject says it all. it has to be a LN2 because of class rules. but its for circle track. ive spent most of the day reading and planning and have a pretty decent plan but i am curious what people have done or would recommend. ive build a bunch of ford motors but this is my first GM motor. i know about pushrods and valve train geometry. from what ive learned today the LN2 isnt that supported by the aftermarket community. so currently im looking at molnar rods and wiseco pistons. and cams from CCW. 1.6 rocker upgrade. balance shaft delete. i read mention of someone using ecotec pistons in an LN2? but i cant seem to find that post again. i normally go for long rod builds but have only been able to find 5.590" rods for this particular build, excluding the light weight ones that need to have the crank ground. I admit that i am not the know all end all and im very interested in learning about this motor and this build. Thanks Ben.

Ben,
Besides the LN2 restriction, what other rules do you need to follow? I'm slowly building a street/track car using 98-up block, 97-down rotating assembly, speed pro pistons, CCW stage 3 cam and lifters, radically modified 94-97 head with +1mm SS valves, 4/2/1 tri Y header, and MegaSquirt 3.57X standalone for spark and fueling. Search the forum for anything MadJack has shared as he's accurate and knowledgeable. No need to delete the non-existent balance shaft.

Blocks
98-up blocks have provision for cam position sensor which enables OBD2 computers using software like HP Tuners to work.

Cranks
94-97 and 98-up have different positioning for the crank position sensor trigger. Otherwise, they are both pretty strong.

Rods
Stock rods are forged and reasonably strong. Just have your machine shop install new bolts/nuts. ARP is a step up. Aftermarket rods are good but not essential.

Pistons
I'm using Speed Pro Hypereutectic pistons as mine is naturally aspirated and forged pistons aren't needed.
94-97 pistons have a deeper dish and are .030" shorter compression height. If you have the machine shop offset grind the crank by .015" you can get a bit more displacement but you'll need to make sure you can get bearings in the right size. 98-up pistons have .030 more compression height which gives zero deck height with a stock crank throw. I chose to use a stock crank and had the machine shop remove .030" and used the 94-97 pistons at zero deck height.

Heads
94-97 crack easily but have an open chamber and better exhaust port. 94-97 Intake port isn't as good as the 98-up. Exhaust port on the 98-up is terrible and is very small. Rockers on the 94-97 are non roller but use guide plates. 98-up are roller fulcrum but only 1.52/1 ratio. MadJack has a lot of input about rockers on the forum.

Other
Make sure you get the right head gasket. 94-97 has a different coolant flow vs the 98-up. You can tell by the valve cover. 94-97 has a ribbed design while the 98-up is smooth. They have a different bolt pattern too.

Best of luck
dennis