Are 706 heads better than 862?

Are 706 heads better than 862?

The 706Vortec heads are even slightly superior to the commonly found 862 heads. The reason is that the 706 heads are SPM (semi-permanent mold) made, while the 862 heads are sand cast. The SPM method is considered to be a more consistent process, but once you port the 862 head, any difference to the 706 head goes away.

How good are 241 heads?

The 241 heads were used on 5.7L LS1 applications and are considered by many to be just a minor step up in performance from the 706. In terms of peak flow, the 241 heads offered 242 cfm at 0.700-inch lift from the 199cc intake ports, and 204 cfm from the 71cc exhaust ports.

What heads on LS3?

The LS3 821 heads had hollow-stem valves, as did the LSA supercharged engine with the 863 heads. Heads for the LS9 used titanium intake valves like the LS7. The main difference between and LSA and LS9 head are the valves.

Are 241 heads any good?

What heads came on the LQ4?

The 1999-2000 LQ4 had cast iron cylinder heads. All others had aluminum heads.

What heads are on a LQ4?

The LQ4 featured cathedral-port heads that offered peak intake flow numbers near 245 cfm. By contrast, the LY6 featured LS3-style, rec-port heads that flowed as much as 315 cfm. The two heads shared similar exhaust flow numbers.

What LS heads are best?

The LS6 was designed specifically by GM to surpass the LS1 as the best performance head, and it did such a good job that the “243” casting was recycled on the LS2. Aside from the LQ9, which is a copy of the LS6, these are the best performing of the OEM cathedral ports.

What’s the difference between LS1 heads and LS6 heads?

Later engines like the truck-spec LQ9 and LQ4 used the exact same port design as the LS6’s 243 heads, but had 6 cc larger combustion chambers. There are three basic differences between the LS1 and LS6 heads. The first has to do with port shape.

Should I port my LS1 heads for 243’s?

If you have a set of perfectly good LS1 heads, there’s no sense in tossing them for the 243’s if you have any experience in basic porting. Gasket-matching, bowl-blending and smoothing out the shortside-turn radius will easily net you another 10 cfm in flow or more, and porting is practically free if you’ve got a die grinder and a few bits.

What are the casting numbers for a head cylinder?

CYLINDER HEAD CASTING NUMBERS Casting # (last 3 digits) Desc Int./Ex. Valves Chamber (cc) 241 LS1 2.000 / 1.550 67 cc 243 / 799 / 823 LS1 / LS6 2.000 / 1.550 65 cc 706 / 862 / 895 LM4 / LM7 / LR4 1.890 / 1.550 61 cc 853 / 806 / 933 LS1 (perimeter) 2.000 / 1.550 67 cc

What kind of engine has 243 heads on it?

The 243 head came on the more powerful LS6 engine from 2001 to 2006, and was used in C5 Corvettes. Later engines like the truck-spec LQ9 and LQ4 used the exact same port design as the LS6’s 243 heads, but had 6 cc larger combustion chambers.