383 kit

[dyeager535]

You have any input/first hand knowledge of the pro-topline Vortec "replacements"?

From what I've seen of pro-toplines *claims*, they should be a better head for about the same cost as stock Vortecs. I've seen pairs new, complete, for $500. The claims/attributes are same/better flow, thicker castings and better springs to name a few things. Not sure if 2.02's are optional on those or not.

My personal view is that a Vortec styled head (minus all the stock Vortec shortcomings) for a *carbed* street motor about can't be beat for the cost.

Vortec carbed intakes are not much, if any, more than non-Vortec intakes, and they work extremely well.

I guess when looking at a 383, depending on what gas you want to run, etc., the 64CC chambers are a bit restrictive.

 

[Mad-Dog]

the vortec's are a good value and the flow numbers are right up there with the best of them.... it's not the 64cc chamber that's restrictive, it's the exhaust port that hurts em on the top-end but motors that built for torque don't care anyway right.
i don't have any knowledgew of Pro toplines units but i know everyone makes a better vortec than GM

 

[Smitty]

Just curious about what RPM range you consider "Top end"? That might help him decide if these heads are even worth considering for his situation. I just don't have any first hand experience with the vortec heads so I wouldn't be able to help.

 

[Mad-Dog]

Anything above 4500 rpm.... i am probably overly critical when describing the flow attributes of heads because none of my engines are built for bottom-end, strictly mid-range grunt and top-end rush.
i don't know if you've been to my web page and read the specs on my latest creation but it's not my daily driver and is way too radical for rock crawling or trail riding, it loves the wide open spaces, power-line roads and stomping the crap outta most street cars , the exhaust note gives it away but they just don't realize what's under the hood.

i looked at GM vortec's and was impressed with their numbers but after factoring in the added expense of bigger valves, upgraded springs and elongating the push-rod guide tubes then discovering they were prone to cracking beyond repair if they got a little too hot i decided they were not for me but will probabaly work fine for someone else that does'nt want to use a high-lift cam and spends most of their time cruising trails

 

[beater_k20]

The GM vortecs have a bad habit of cracking and it's not repairable, if you in sist on Vortecs then buy the ones that World makes, their much better.

i have never heard of a cracked set of Vortec heads, nor has my buddy who has worked a GM Parts counter for the last 12 years. do you have some sort of proof to back this statement up? at any rate, he's looking at buying a brand new set of heads. keep the engine cool, and any issues you might have had with cracking will not exist.

the Dart 180s may be a little overkill for this application. also, stick with a 64cc combustion chamber, or adjust teh compression accordingly.