Going to be putting a motor together for my monte soon out of some parts I have laying around, it’s going to consist of:

2002 lq4 shortblock
823 rectangle port heads
NNBS rectangle port intake
WARR 102mm dbc tb
1-3/4” long tube headers
PAC 1219 valvesprings
and then I have a 228/236 .588”/.601” 112lsa cam from my LS1, I’m thinking it’ll work okay with the square ports because of the larger specs on the exhaust side, am I right in thinking that or should I sell it and go with an “ls3” grind?

id also like to get it to at least 10:1 compression, will just the headswap get me there with the stock headgaskets or should I go to a .040” and maybe deck the heads too, not afraid of high 10’s compression either just would like at least 10 without spending too much

does this sound like a decent combo to you guys? Would like it to go high 6’s in a 3100lb monte with a transbrake th350 and 3.73 gear with a 26” tire, think this will get me there?

 

I see a flaw.... the heavy valves need to be replaced with lightweight LS3 hollow valves. Valve weight can literally make or break performance output in the real world.

 

https://www.ferrea.com/Chevrolet-Com...ect_model=2756

These L92 hollow stem valve walls aren't as thin as the GM LS3 hollow stem valves and are only about 20g heavier. You also won't have to deal with the taller valve stem heights that your going to find when using the stock LS3 valves.

LS3 hollow stems have a longer stem length than the stock L92 truck valves.

 

i need hollow valves in something that’s gonna make peak power at 6500rpm ??

 

Everyone has a opinion.

 

I guess you need to ask your self how often are going to be in this range and you if want to leave anything on the table ? You are getting into a range you will benefit from lighter valves. The way I see it if you're not going to spend a lot of time in the upper range we shouldn't be talking about which valves, but which heads. The L92 valve for it's size is fairly light 109g But LS3 at 89g , is the real bargain . Weight saving of 20 grams is substantial .

 

Here's a rant for ya!

People looking to pick up those small amounts of horsepower will do the little things so if your building an engine to spend most of its time up in the RPM as with a racing engine then you need to have a valve train suitable for that. So toss the hydraulic cam and go with a LLSR, only run CNC ported heads and have them outfitted with some of the best valves money can by and while your at it get them machined to accept the Crower or Jesel shaft mounted rocker arms and run the stiffest push rod you can find.

Go as fast as your wallet will let you because going fast is not cheap.....

 

I think I’ll run this setup for now and when the budget allows go to a larger cam, better springs and ls3 valves