Official L92/L76 and LS3 Heads/Intake FAQ and Information
- L92/L76 and LS3 FAQ.
Q. What are the differences between L92/LS3 and LS2 style heads?
A. The L92/LS3 heads have larger relocated valves, larger rectangular intake ports (as opposed to the LS2's cathedral port), as well as increased intake and exhaust flow.
Q. What are the differences between L92 and LS3 heads?
A. LS3 heads ship with lighter valves and better valvesprings than standard L92 heads. Everything else is identical.
Q. What headgaskets can I use with L92/LS3 heads?
A. You CAN NOT use LS2 headgakets. You need a 4.060 bore headgasket which is OEM equipment on all vehicles with L92 heads or LS3 heads (see below). Many aftermarket manufacturers offer 4.060 head gaskets in different thicknesses to raise or lower compression.
Q. What are the differences between L76 and LS3 intake?
A. L92 and LS3 intake manifolds share the same castings and can be used interchangeably. Although the LS3 also has an external "beauty" cover, the most noteable difference in the manifolds themselves is the MAP sensor.
The L76 manifold uses an LS2 MAP sensor with a clip style mount.
The LS3 manifold uses a slightly larger MAP sensor (p/n: 88988583) that is bolted down.
Q. Where can I find L92/L76 or LS3 heads and intake?
A. The L92 Heads are OEM equipment on
I was @ 429/391 on my first try at tuning and full torque management. M6 little Katech stage II 276/576 116lsa. But went back to LS2 heads for Maggie. Heads milled for stock compression and little porting. That reminds me I still need to sell that kit.
Trek Actual :-)ASE 35 + yrs. Mechanic---- RED SAP GRILs, STOCK LS2, MONSTER LEVEL 3.5, LEVEL4 next?, KOOKS, G-Force 1320 AXLEs, STUBs, SUPER CHILLER, MAGGIE 112, ALKY.COM, KB BAP, ELITE CATCH CAN, NOLTEC, HARROP, BMR, MAGNAFLOW, HOTCHKIS BARs, JHP POD, HP TUNERS, PLX WIDE BAND, BLUE TOOTH,06 DOOR LOCK, RADIO CONTROLS & TAILS.
Just found your thread thank you for getting my info on there. As for post 17 I did all the install with the help of the other GTO's in Tulsa, we will get together to install anything. Had the intake ported and polished @ LS2 PortWorks. Guess I will take it back to the turner to try to squeez out another 2 rwhp to get to the top. Track time are in my sig.
404 cid milled L92 heads built by John and Rick performance shop!
best r/t .000
best 1/4 11.85 MPH 116.75 old numbers.
Proud member of the Tulsa Goat Brigade!
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