305 (059) vortec heads vs L69 heads.

[liquidh8]

I have the Vortecs on my 350. 350 horse, forged pistons, 150 shot of n2o, EFI. I put 40k miles on it (100 miles a day DD) and countless bottle of gas through it. No issues what so ever. Oh, and I worked in an independent shop when these heads were only a few years old on cars. GM has gasket issues, as was stated above. And the heads or no worse than others. My buddy runs a machine shop in Bucks County, and has redid all my heads.

 

[Brother Al]

You'd initially said they are on a truck with a blown engine, hence my point about them cracking when overheated. .. just didnt want you to potentially throw your money away on heads that are probably cracked. Wow, haven't been to the Crankshaft Coalition site in a very long time... site is massive now.

I still say that'd be better off retooling your "416" or "601" heads. I'd imagine the "059" vortecs flow more with good velocity, but I haven't heard of anything performance-wise about Vortec 305 heads...

If you were to compare the later-LG4, L69, LO3, & L30, the main differences in the shortblock is essentially the camshaft, with the L69 winning by a long shot, but the roller cam has less friction... We'll eliminate the LG4 & LO3.

The L69 & L30 heads, induction, & accessories factor the rest of the power equation. If you compare the exhaust on an L69 F-Body to a L30 C/K truck.. very similar dimensions. Accessory losses between the L69 & L30 are about the same: L69 multibelt with electric fan vs L30 with serp belt and mechanical fan... induction L69: E4ME... L30: TBI... carb has the performance edge... intakes both leave a lot of room for improvement, but the TBI intake is VERY restrictive.....
so, in this basic theory, you are looking at maybe about 10 hp with the L30 Vortecs at a relatively high expense... however, Vortecs are limited in several ways, unless you modify them. I have no idea what the mod. limits are on those "059" heads, but I'm sure they are similar to the L31 head polish & porting limits. The "416" & "601" heads have some decent potentials for 305's, short of aftermarket heads and could very possibly surpass that 10hp difference with some of the basic stuff I mentioned doing in my first post.

 

[MUELLERBU]

FYI
am I missing something as these are unworked head numbers & seem pretty good

 

[86 Grand prix]

I've pulled two set now from pull a parts both were good. Your results may vary.

 

[88ss408]

I have pulled 3 set of vortecs so far and 2 of them where cracked.
Now the L69 heads you have a good heads with a clean up. If you swap over to the vortecs you will need the valve covers the rockers and a vortex intake.
For the cost of the swap I don't think you will gain much