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SBC heads?

Truck or car Dyno numbers dont lie..... It's a fact as you said that high flow numbers usually change low end torque but the newer heads are over coming this issue clearly and the power curve is through out the rpm range depending on the cam you have. If Vortecs produce 30 (real world horse) bolting them up then the World Product's Sportman heads would double that. The plug is located closer to the center, they have fast burn chamber's etc. look it up if your really interested but I believe most everyone that has run either would agree.They are a better investment, some time down the road you might build a 350 h.p. sm. block and they would really come in handy, either set is a good improvement. My point is only that for a few more dollars they are a better purchase! No that's not shipped but neither is the Vortec price! Good luck with your investment!
 
Probably a little late to ask, but sure, if you've got some around, I wouldn't mind you checking to see if any differences exist that might change compression ratio!
 
You are right, they don't lie.

http://yeagerd.home.mindspring.com/TablePics/K5TPI350.jpg

Show me the sportsmans (2's, all I can find numbers on) beating that, with just a head swap, all other components the same. I already checked, they don't. They are almost identical, unless I go with 2.02/1.94 valves. (and the flow numbers I plugged into DD2K for Sportsman 2's are BASED on 2.02/1.6 valves, that Vortec dyno guesstimate at 1.94/1.5) Doesn't seem to hurt the *visible* low end, but I haven't run the specs through Engine Analyzer, which shows under 2000RPM numbers.

So doubling the Vortecs power won't happen. I'm going for a balance between max economy and max torque, and those numbers are about as high as I can go, and still expect to have both great low end, and great economy, AND have no problems with the ECM. (yes, that could be worked around, gonna try with a stock PROM first though)

I don't agree that they are a few dollars more either. Complete Vortecs are $238 (IIRC) each from SDPC, which is under $500. Shipping even if $100 would put that number at $600, plus intake, $750. If you watch eBay or look around, you will see them under that even, brand new.

So, $750 for a pair of Sportsmans, (unshipped and no intake)or $750 for a pair of Vortecs, shipped, and with the intake.

I checked the flow numbers again, the Vortecs (1.94/1.5)beat the Sportsman 2's (in 2.02/1.6) in most every flow category, except over .500 lift. Since I won't be running that much lift with my truck cam, (and I doubt many here care about .600 lift numbers, which is where the Sportsmans win) the Vortecs actually outperform the Sportsman 2's.
 
Argueing over heads with you seems quite analretentive, anyone can find facts to support there choice, whether it be heads,pistons etc.I know from real world tests that they are clearly the better choice for a performance mod.I have a cousin that works for a speed shop, they have dyno'd both as well as many others and desk top dyno or computer programs are well know to produce false numbers when compared to a REAL dyno machine.I am not trying to change your mind and really dont care how you feel about it but I am open minded and have agreed that Vortec's are a good modification. All I am saying is for a few more dollars sportman's are a better buy. This is the third time I have said this.Since you are obviously on ebay alot then just ask "BigBlock Shaun" (one of the QUALITY engine builders on there)what his sm. blocks have dynoed with ea. set, he dyno's every engine he sells and is very good at what he does! I am sure you will respond with another argument but that's ok. You are right (like I have said) they are good heads. I would like to apologize to the guy that started this thread, I didn't mean for this to turn into an argument but never the less hope you have got the answer or something from it! GOOD LUCK
 
Decking the block is when you shave a few thousandths off the mounting surface of the block to head. It gives you some cheap hp by raising the compression ratio a little. If you want some good power, port and polish those heads then do a stroker kit.
 
Based on your private messages with me, I'm taking a deep breath...ahh..better now : )

The fact is, the Vortecs outflow Sportsmans through any meaningful lift #'s (for daily driving). Thats not something I made up.

However, if the chamber is the same (fast burn) but things such as port design, finish work, valve size, plug placement, etc. are different, and not accounted for, the overall numbers may appear different when all is said and done.

This doesn't/didn't turn into an argument, as I was just stating facts to back up my side of the discussion, as I believe, were you.

I think both of us would agree, that until there is a comparison of back to back engines, with the ONLY difference being the cylinder heads, the results are pointless. One design may excel given different components than the other, but then you are arguing apples to oranges, and I don't like doing that.

To be totally honest, I didn't look into any other head designs, besides old school stock stuff, then the Vortecs when I was "designing" my motor. I generally don't delve into the intricacies of things unless I am going to use them, or need it later, so I don't know a lot about the Sportsman 2's. The only thing I could quickly and easily find to compare the two are the head flow files.

As to desktop dyno, even on here it was shown to be within I believe 5% of real world dyno testing, (as well as almost dead on using HP vs ET calculators) and of course, David Vizard has already discovered that variations between different real dyno's is a fact. I don't use DD2K as a crutch, and I'd never say "my motor will make 425ft lbs of torque" without including that those numbers are A) not real world, and B) not rear wheel. However, being proven within 5% accurate, it is *invaluable* when checking different combinations, without the expensive dyno time, and worse, parts acquisition for testing.

I don't believe talking about anything in depth is anal retentive, its called "learning" and if I wasn't learning something, I wouldn't have paid attention to your comment about Sportsman Plug placement, which I didn't know before.

I don't believe anyone should see this as a waste of a discussion, you brought some heads to the table, I brought some heads to the table, and everyone has a chance to see what two people think and know about them. If anything, discussions such as this help people make up their own minds.
 
vortec heads dont need center bolt valve covers.. there is a conversion kit out there... ($60) that I am going to buy.. you can even get it on ebay... where you can use your old style valve covers. I am going to do that once my truck is on the road. I like my M/T valve covers better than these low profile sloppy things.....
just my input...
http://68.45.68.102
 
I dunno about those valve cover adapters. Just my opinion (because I was told stock centerbolts wouldn't clear roller rockers, hah!) but that adds ANOTHER two gaskets to the already leak prone valve covers.

Obviously the adapters are fancy, as they use O-rings, and still bolt in the center, but the perimeter valve covers still probably tend to leak.

I guess $60 isn't bad, thought they were like double that when I checked into them a year back or so.

Since I modified my stock center bolts to clear, I didn't research any further to see what kind of centerbolt valve cover options there were. I just knew I wasn't interested in something non stock looking, and there weren't many choices in that category.
 
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