JamesHigdon Posted August 24, 2011 Report Share Posted August 24, 2011 Note-this is relating to the Pure Stock class First off, this thread is not to start a problem or because I dislike the track in any way, quite the opposite as we sponsor a couple of cars there and are always looking for cheap ways to keep them on the track. We are looking for a "junkyard" motor for a pure stock we are involved in and have found it harder and harder to find usable "pre-vortec" 350s. I understand in the 90's a ban on what was then an exotic and new vortec head made sense but now, with them being the most recently mass produced GM Gen1 350 head, it seems the ban of them may be costing money. We have found it much easier and cheaper to buy craigslist or junkyard Vortec heads in usable as found condition then 882s, 461s, 993s or the like. Am I missing the point on the Vortec ban? If GM cars where allowed Vortec heads with cast iron GMPP vortec-carb manifolds what would be the net negative? In a class where the average racer should have no more than $300 or $400 in a set of stock rebuilt heads what would be the difference of allowing a later model, more easily accessible truck head? Again, there is NO reason for this to get negative, I am simply looking at ways to save us and the guy we sponsor some money. James Higdon Link to comment Share on other sites More sharing options...
rebelracewriter Posted August 24, 2011 Report Share Posted August 24, 2011 It's been a while, and I've slept a time or two.....So I'm sure I'll be corrected if incorrect You would probably also need to change the intake so you start adding and opening up more cans o worms....There were a couple other swap issues as I recall....like retro-fitting the temp. sending unit and stock exhaust manifold fit Again I'm trying to draw on memory from quite a while back......You might do some conversion research to confirm... Link to comment Share on other sites More sharing options...
JamesHigdon Posted August 24, 2011 Author Report Share Posted August 24, 2011 It's been a while, and I've slept a time or two.....So I'm sure I'll be corrected if incorrect You would probably also need to change the intake so you start adding and opening up more cans o worms....There were a couple other swap issues as I recall....like retro-fitting the temp. sending unit and stock exhaust manifold fit Again I'm trying to draw on memory from quite a while back......You might do some conversion research to confirm... We use both early and late heads in the shop quite a bit, you are right in that the biggest concern is the intake manifold as GM never made a production carbureted vortec headed motor. Gmpp does however make a cast iron vortec manifold to take a carb for just this case. The temp. sender issue would be mute for us (and most others I think) as we run a parts store water temp gauge that comes with a bunch of different adapters and I do know manifolds and headers swap back and forth with ease. The fact that most vortec motors came with roller cams could be an issue but again if that's what is currently in the junkyards then that's what's cheap? Link to comment Share on other sites More sharing options...
DirtRacer9s Posted August 24, 2011 Report Share Posted August 24, 2011 Arent the combustion chambers smaller than allowed. All I could find was 64cc chambers for the vortecs. I didnt look real hard but our rules are 68cc. If you are looking for engines go to u-pull-it. They have several trucks with crate engines in them. They also have tons of 993 and 882 heads out there and 487s every now and then. I just pulled a set of 441s off of one of there cars this past sunday. Just because one head on the engine is not what your looking for doesnt mean the other is the same. We have seen this many times. You just have to go through and look and believe me they are out there. Link to comment Share on other sites More sharing options...
rebelracewriter Posted August 24, 2011 Report Share Posted August 24, 2011 James, I got this info off Summit Racing.... http://www.summitracing.com/parts/NAL-12558060/ These cast iron Vortec cylinder heads will fit 1958 and later small block Chevy engines, and offer a 20 to 40 HP increase over earlier cast iron small block heads. Features include 64cc fast burn combustion chambers, 170cc intake runners, and a high-velocity LT1 port design. They require the use of a Vortec-style intake and self-aligning rocker arms, and come complete with 1.94 in. intake/1.50 in. exhaust valves, springs, and retainers. How much would they increase compression ratio/could a stock 350 handle it under racing conditions Would it still be able to pull vacuum(since I'm guessing timing would need to be altered) Link to comment Share on other sites More sharing options...
JamesHigdon Posted August 25, 2011 Author Report Share Posted August 25, 2011 Ok, combustion chamber size I hadn't though of and that probably is a deal breaker. More compression means more power and a decided advantage over older heads. I also ran some numbers this afternoon and a set of later vortec heads can make as much as a 25 to 30 HP difference over typical late 70's or early 80's 350 heads. Self aligning rockers, intake, more expensive gaskets, valve covers and the like I still don't think would be a huge deal but the compression and power advantage would pretty much obsolete every other head on the track. Not a good idea right now! Link to comment Share on other sites More sharing options...
dancer52 Posted August 26, 2011 Report Share Posted August 26, 2011 how about if you ran dished pistons with them? You can run stock intakes on them but the heads have to be re drilled for them....I also think there is a steel intake made for these now...but I could be wrong. I wonder more about the imca eq head....supposed to be the same as stock open chamber heads.... Link to comment Share on other sites More sharing options...
1955chevy33 Posted August 30, 2011 Report Share Posted August 30, 2011 Vortec is a whole other can of worms . Just move up to streetstock then you can run vortec. Remember vortec can only use castiron intake unless you modify the 2101 to fit,which is also another problem. The vortec castiron intake weighs about 75 pounds so that helps even out some of the horsepower gain.Older heads are not that expensive. I see lots of older heads on here advertised reasonably or the junk yards have lots for purestock engines. JMO Link to comment Share on other sites More sharing options...
poorboy Posted August 30, 2011 Report Share Posted August 30, 2011 When did Vortec heads come out? Wasn't it like in 1988? How can a 20 year old stock head be considered illegal, it doesn't make sense to me. Link to comment Share on other sites More sharing options...
DirtRacer9s Posted August 30, 2011 Report Share Posted August 30, 2011 When did Vortec heads come out? Wasn't it like in 1988? How can a 20 year old stock head be considered illegal, it doesn't make sense to me. The same reason why the stock camel humps are illegal and they are 40 plus years old. It doesnt matter how old they are if the combustion chamber is smaller than 68cc than they are illegal. There may be other reasons why they are not allowed but cc rule works for me. Link to comment Share on other sites More sharing options...
JamesHigdon Posted September 2, 2011 Author Report Share Posted September 2, 2011 The biggest problem (to me) is that the Vortec heads flow so well they would obsolete most everything else. I've run numbers on the vortec up against many touched up "good" factory heads and many more cheap after-market heads and the velocity with low-lift builds much more torque in the low and mid-range. The other issue is vortec heads are like fuel injection or automatic transmissions used to be, not as many people can work with them so there is more room to change things without getting noticed. My questions is if you are trying to run a later model Caprice what motor are you supposed to run in that? Those car run LT-1 heads and if memory serves you can get a cast iron manifold for them? Link to comment Share on other sites More sharing options...
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