Etec aluminum heads vs stock vortec heads

[BOOT]

200cc ran great on the 350 in my Express van. Offshore castings flowed about 265 cfm with a decent valve job. Also the same casting runs great on my 383 after Lloyd Elliot got his hands on them.

And single planes run fine on the street if you know what your doing But many find out that they don't.

 

[L31MaxExpress]

And single planes run fine on the street if you know what your doing But many find out that they don't.

I know, I ran a vic jr 2bbl on my TBI Vortec engine and a vic jr 4bbl on the 305 in my Corvette.

200cc heads still build plenty of torque if cammed correctly, especially in a port fuel injected application. The 200cc aluminun heads ran better all around than the Vortecs. I was actually able to put more than 27-28° of timing into it on pump gas. I ran 34° total at 2,800 rpm on 87 octane with the aluminum heads at 9.7:1.

 

[BOOT]

Vortec heads use less timing because of plug position(& swirl), the further it is into the chamber the less advance you need. More timing advance is not always a good thing, more of a necessary evil/loss since combustion works against the rising piston. LS engines are more efficient and need less advance, obviously a much better head design in multiple ways.

I run 200cc heads on 350's in my striped out cars cause they don't need low end for how I set them up, trucks are heavy. Vortecs are a good low-mid range head by design, they also rpm enough for street builds. Support 350-400hp in stock form depending on cam, comp and so on. Straight from a gm engineer that did extensive testing on the heads.

 

[L31MaxExpress]

Vortec heads use less timing because of plug position(& swirl), the further it is into the chamber the less advance you need. More timing advance is not always a good thing, more of a necessary evil/loss since combustion works against the rising piston. LS engines are more efficient and need less advance, obviously a much better head design in multiple ways.

I run 200cc heads on 350's in my striped out cars cause they don't need low end for how I set them up, trucks are heavy. Vortecs are a good low-mid range head by design, they also rpm enough for street builds. Support 350-400hp in stock form depending on cam, comp and so on. Straight from a gm engineer that did extensive testing on the heads.

Mine was knock limited on 93 octane, not because it needed less timing. Made alot more torque on E85. I made just as much low-speed torque with the 200cc heads and the 200 cc heads ran away from the stock vortecs at about 2,000 rpm and above.

 

[BOOT]

Mine was knock limited on 93 octane, not because it needed less timing. Made alot more torque on E85. I made just as much low-speed torque with the 200cc heads and the 200 cc heads ran away from the stock vortecs at about 2,000 rpm and above.

E85 is a high volume fuel and that increased volume cools good, why it compliments boost/compressed/heated air power adders. Some NA engines are set up to run cool already and don't benefit from it much. Many factors can account for head swap differences. Same setup just diff heads for mine, the vortecs were loads better down low and everywhere else than some 200cc heads. But those were Fresh New vortecs, not some old set with a ton of miles. The high mileage ones that I've pulled off were in need of a lot and comparing them to fresh 200cc heads of course the New heads would out perform them.

 

[L31MaxExpress]

E85 is a high volume fuel and that increased volume cools good, why it compliments boost/compressed/heated air power adders. Some NA engines are set up to run cool already and don't benefit from it much. Many factors can account for head swap differences. Same setup just diff heads for mine, the vortecs were loads better down low and everywhere else than some 200cc heads. But those were Fresh New vortecs, not some old set with a ton of miles. The high mileage ones that I've pulled off were in need of a lot and comparing them to fresh 200cc heads of course the New heads would out perform them.

Comparing to slightly worked 906 Vortecs milled 0.020", 2.02/1.60 valves, 787 retainers, 918 springs with the chamber slightly deshrouded around the valves and exhaust porting that had about 15K miles on them. Vortecs flowed 245/180 @ 0.500. The 200s flowed alot more and the 218/228 cam with 1.7 rockers had enough lift to really bring them alive. I had a 2,800 stall converter and 5.13 gears. Even down at 2,000 rpm the 200cc heads moved a good bit more air.

 

[BOOT]

Comparing to slightly worked 906 Vortecs milled 0.020", 2.02/1.60 valves, 787 retainers, 918 springs with the chamber slightly deshrouded around the valves and exhaust porting that had about 15K miles on them. Vortecs flowed 245/180 @ 0.500. The 200s flowed alot more and the 218/228 cam with 1.7 rockers had enough lift to really bring them alive. I had a 2,800 stall converter and 5.13 gears. Even down at 2,000 rpm the 200cc heads moved a good bit more air.

Everything I've seen or people that I talked to said vortecs are touchy and easy to mess up.

Links show what Dart recommends for either size. I know other head manufacturers have said similar but I was on Dart's site recently while making the SHP vids. Now some may say different but unless I know the person, their build details & their skill level. I won't recommend a 200cc head for a 350 truck. I've seen my share of eye bigger than stomach SBC situations and then disappointment that leads to LS swaps.

SHP | Dart Machinery

dartheads.com

SHP | Dart Machinery

dartheads.com

 

[2drXmobb]

I read an article for the etec heads and said they were the best for a mild build. My goals for this truck is to build a high torque monster without going 383. I thought about using aus or 5.0 motive bigger injectors as well, will that make my vehicle run to rich with the bigger injectors? It's oem style spiders but has a larger flow rate. I don't want to do the marine intake because it seems cumbersome.

 

[Erik the Awful]

If you're aiming for torque, have the Vortec heads magnafluxed. If they check out good, do a mild cleanup porting job and reuse them.

 

[2drXmobb]

What's magnafluxed and I hear if you port the vortec heads to much they would be bad , I wonder if you can put bigger valve stems in the OEM head