Don Nguyen

iTrader: (2)

I am starting out with a LS2 block with the complete rotating assembly. My goal is to hit around 450-500 rwhp.

I am aiming for the best bang for the buck route, so obviously I am going to be looking at LS3 heads.

Since the block is going to already out of the car, I heard that it is a good idea to valve reliefs cut into the pistons to allow for a more aggressive cam or simply to be on the same side, is that correct?

Also, what's a good intake manifold and throttle body to pair all of this up with? I know bigger is not always better, and it is based on the displacement, etc.

thanks.

-Don

Zfan

Depends on what you want to do with it, street or strip or a combonation of both. LS2 short block, LS3 heads and intake with a cam that its your needs. I just built that combo with an EPS 230/242 duration .600/.605 Lift 113 lsa cam. Not a bad idea to flycut pistons if you have it apart anyway.

It's going in my Datsun 240Z with a 4L80E behind it.

sic7camaro

iTrader: (21)

Victor jr and accufab 4150 tb.mill the heads .30 for 64-65cc and get a custom cam.im doing the same but with lg g6x3 cam and I should expect. 470rwhp high side.what are your plans

Don Nguyen

iTrader: (2)

I knew I forgot something. It is going to be a street driven car with possibly some road racing.

So I should mill the heads .30 to get a higher compression ratio, correct? What gasket do I run if I do that?

-Don

Tainted

iTrader: (9)

id stick with cathedral heads on a 4.0" bore. What you need is some nice trick flows or AFR's

Don Nguyen

iTrader: (2)

I don't think I want to spend that much on heads.

KingPin1094

iTrader: (12)

Im in the same boat with you. i have an LQ9 though and looking for the same power outputs. Im going to do a FAST 92/92 setup with TFS 225cc heads, and a custom EPS cam to help match my build and reach my goals. I think im gonna get pistons with valve reliefs in them to be safe, and hopefully run 11:1 compression. I plan to DD the car and occasional drag strip. I dont know if this helps, but that is what im going to do with my build.

Don Nguyen

iTrader: (2)

Any input helps, since it gives me more topics to research.

Is there any reason to go with 92mm tb and intake over a 102mm? Is 102mm just unnecessarily big for this engine size?

Machine-Master

I run a 6.0 with factory l92 heads cut .025 and use a lunati camshaft built for that setup, it is instant HP, I think after using the L92 heads someone would not go back to the ls1 style,

Tainted

iTrader: (9)

Go for the 102mm intake! The 102mm tb is however overkill. 90mm tb is plenty.

If you dont wanna spend big bucks on afr or tfs heads then you can check out prc stuff or the tfs as cast 220 heads.

Also, ls3 heads with big *** 2.165" valve on tiny 4.0" bore is a no no. Yea you can make power, but you are limiting yourself. Valve shrouding, ptv clearance woes, cant run a big cam withoit flycut or pistons, cant mill much due to ptv for compression. You are simply much better off staying cathedral.

Don Nguyen

iTrader: (2)

I think you're the first that I read to say not to go with LS3 heads on a LS2 block.

Tainted

iTrader: (9)

thats because people dont do their damn research and think jsut because they have better flow numbers that they are superior and that isnt the case. Do a search, tony mamo pat g predator, the list goes on and on of actual KNOWLEDGEABLE people that have the facts, testing, and results to back up their statements. LS3 heads on the small bore motors isnt the way to go. They have their place, dont get me wrong, but on a smaller bore, there are better options.

your real advantage of the ls3 top end is the intake, its leaps and bounds better than the ls6 intake, and it can be had really cheap.

Tainted

iTrader: (9)

here, start reading.

I suggest some others do the same, all it takes is a search!

Patrick G, 6.0 switched l92 heads in favor of AFR gained serious power:
https://ls1tech.com/forums/dynamomet...k-results.html

LS3 heads switched to TFS 235's picked up over 30rwhp:
https://ls1tech.com/forums/dynamomet...flow-235s.html

Don Nguyen

iTrader: (2)

Cool. Thanks for the links. I'll take a look at them.

-Don

Sales@Tick

iTrader: (3)

I agree with Tainted, valve shrouding is a big issue as is P to V. If you do go with LS3 heads I would fly-cut so you can do whatever you want with the compression and camshaft and aren't limited and then left worrying, "what if it hits one day?"

KingPin1094

iTrader: (12)

The reason im going with the 92/92 setup is because it was already on the car when i bought it. And the hp gains of a 102mm over the 92mm are not enough for me to switch it out.

Don Nguyen

iTrader: (2)

Going with the AFR 230 V2 heads.

Kind of a side note. If I decide to run an LS3 block instead, would I still be able to use the AFR 230 V2 heads on it or is it not as ideal as it is on an LS2 block?

Tainted

iTrader: (9)

Those are nice heads, just make sure you get some light valves and good springs.

You can reuse the afr heads on any ls motor as long as its a 4.0+ bore

Don Nguyen

iTrader: (2)

I am going to be running the valves/springs that came on the head from AFR as is. Should be good?

Tainted

iTrader: (9)

I dunno what they come with, sometimes they have some heavy *** valves though. May want to check