whats better? double hump heads or vortecs? 355 CId, xe274 cam, 3.73 gears. 700r4

Everything I've seen, the Vortecs are a big step up from the older heads.

if you are wanting camel hump heads make sure you are getting some with accessory holes...such as these...

3927186....69-70...302/350......Camel hump,64cc chambers,accessory holes
3927187....69-70...350..........Camel hump,64cc chambers,accessory holes
3991492....70......350..........LT1,Camel hump,accessory holes,64cc, straight plug
3991492....70-up................over the counter,Camel hump,64cc, straight or angle plug

I'd definetly go with the Vortec's.

Camel humps are trash, they were the **** back in the day, but now they are just **** 35 year old technology. Leave them to guys building stock motors for old vettes and such.

Actually with that cam your really don't want Vortec's either. By the time you spend all the money to get them machined to work with the lift of that cam, you could buy aftermarket heads. Vortec heads are not performance heads, never were designed to be, never meant to be... They are stock truck heads and require extensive work to make them work in a performance application.

I know it sounds bad for me to bash those heads and then try to sell you mine, but I have some ProTopline heads for sale. They are much better are performance heads. http://www.webpages.uidaho.edu/~osie4078/proheads.htm

Vortecs are way better, the only reason anyone uses the camel humps is because they deliver better than stock performence and can be had for cheap. Also I think that the number of people using the SDPC vortecs and the XE274 cam that are running in the 12's are pretty good proof that the vortecs are a performence head. Now granted they are not as good as those pro topline but they are great for a mild budget minded engine.There have been plenty of high 300hp and low 400hp motors made with unported vortecs, you cant do that with an untouched L05 head so i defenetly wouldnt call them "Just truck heads".

Yes i agree, but i don't get why people would spend all the money to make them work with bigger cams, when in the end you still have stock heads. For the same price or a little more you can get some really good aftermarket heads. Then you have to spend more money to get a vortec specific intake, self-aligning rockers.... not worth it IMO.

better for what? the double humps would be a lot better for mounting acessory probelms not to mention problems created by not having lead fuel to burn.

Run the vortecs, I have a set of 461 humps on my car now and have had vortecs and the vortecs made a noticable difference but not a dramatic difference over the camel humps. Camel humps are a great bargain over the stock heads, mine have a slight port job and the car goes 12.8's. Never ran it with the vortec's though.

It's all a cost / vs power gained equation....

Vortec heads are a great deal...but like it was mentioned, more than a fairly mild cam, and they need work to accomodate that extra lift.

Now Pro Topline makes a set of Vortec "replacement" heads that are already ready for more lift and they come in around $450-600 depending on if you finish 'em yourself, or where you buy 'em.

Then you have to factor in the Vortec intake...if you're carbed, that's not a huge factor.


As for "double hump" heads..

There were ALOT of heads cast w/ the "double hump" markings...only a few were worth anything...

As mentioned some didn't have acc bolt holes...and originally these heads were set up for leaded gas and would need hardened valve seats installed.

However...these have been used for so long, if you look around locally, and at machine shops and such, you can normally find all kinds of GM / and aftermarket heads, "double hump" too that have already been worked and are ready to bolt on...and usually at a MUCH cheaper price than just about any aftermarket head that's any better than stock.

And I wouldn't knock the old heads too much. YES, if you don't know how to port, or don't know someone who does, and money it's a big concern, aftermarket heads are great...

But I've built more than a few motors runnning "ancient, old technology" heads and some of were pretty dam quick...

Not to mention a friend of mine right now running high 11's with a simple, no frills carbed 408, running a set of 492 casting "double hump" heads and these DID have ACC holes, and already came w/ big valves. Sure, he's done some work to 'em...but he got 'em bare, with ALOT of port work done to them for cheap. Even after installing all new hardware, he's still WELL under the cost of any aftermarket head that flows as well as these do....

It's all about what resources you have available and what you want to spend, or how much time you're willing to invest.

Don't forget to check your local machine shops and classfieds for deals...ESPECIALLY around this time of year w/ Christmas coming up...


For example... I just bought a set of heads for a friend of mine's project.. I was BS'ng with my machine shop guy and he had a set of Dart Pro's that had been dropped off at his shop to have 'em ported / flowed / etc etc....they also needed a valve job. Well he did all the work and they guy didn't like the bill.. so they were left there. I got 'em for what my guy had in 'em...and that was a good bit less than what a set of untouched Dart Pro's go for new...

Also, don't forget alot of the "old school" racers race / raced in classes where GM Castings HAD to be used...so there are TONS of modified GM castings that will flow well on any street / strip small block floating around....

Don't forget to check out they guys who race roundy-round...they get some pretty impressive #'s out of GM castings too...





HTH

i couldnt agree with you more about the old technology heads being great ..LOL

there are so many of these cast iron heads around and so many machine shops that you can get a really good set of heads (proper castings are a must i understand this) for half the price of an aftermarket set and still get some awsome performance ....i prefer to run the old technology on my cars as im a carb guy never had a problem with mine ..

we had a 73 camaro we built using double hump heads after it was all said and done we were putting out a little over 500hp at the crank ....LOL....so old technology is fine with me ..

the more these guys buy the aftermarkets the more ill collect the old school stuff in the garage and be happy for many many years to come....

maybe im getting old and stuck in my ways but i like em....LOL..well i really like the price.

c'mon general, you know thats all a bunch of 70's junk smogger crap. Thats all they are!

I have said it before and i will say it again, why spend all the money on GM factory heads when you could by aftermarket heads for a little more.

There are many more variables that go into making power other then what the heads flow. Port velocity, chamber design, spark plug location ... all weigh heavily into the power equation. Now if you want some 35 year old heads that require several crutchs to work, go for it waste your money. Old heads also probably have been rebuilt several time and are then end of their lives. Old heads also will require new valve seats to run on pump gas, new valve guides, and a rebuild. And depending upon what double humps dome pistons to raise compression to a usable level. Combine that with crap bathtub combustion chambers and you will run into detonation problems...

Now vortecs they require tons of machine work, specific parts and are lightweight castings that are prone to cracking. Vortec heads also don't like to be rebuilt alot and will be substantially weakened by having the spring pockets enlarged for bigger springs.

IMHO its not worth rebuilding any stock parts anymore ( heads, rods, cranks...) when there are much better aftermarket parts for a little more. Aftermarket parts will last a lot longer and will be much better.

I would never buy GM heads, but thats me, i would spend my money more wisely. That being said i have some 416 heads on my 305 that i am going to port, but i didn't buy them i already had them.

Anyone that puts 700 dollars into stock castings is wasting money. I agree entirely. Mine were 359. Good enough deal to make it go until I can get some good heads. I was thinking about buying some Dart Pro 1 heads after income tax time this year. Anyone have any experience with them?

I've stated this fact many times, but I'll say it again Go AFR and forget you ever thought about Pro 1's. Both the truck I drive in my sig as well as my bro-in-law are running Pro 1 230cc heads that have been worked over before they were bolted to the engine....my 210's still flowed more at only 70% cnc'd-bottom of the pole heads from AFR. Nothing against them for quality as the Pro 1's are a great head, but when comparing what you get for your investment the AFR's are unbeatible. I dont have the flow sheet copied, but after I had my heads checked out I was comparing numbers in the shops flow book with other heads they did. My 210 AFR outflowed worked over Pro 1 230's by 30 cfm!!! Plus only being 70% cnc the guy that does the porting was pointing out where he could easily get another 20cfm out of mine

As far as combinations are concerned, my pump gas motor with a small .621 lift cam is making more hp at the flywheel than both of the 13.5:1 motors in the family members cars that use over .700 lift cams, require 8" stall convertors and most of all race gas-oh mine is all through the exhaust and their's are open headers too

yeah i forget its impossible to make power out of these junkers...LMAO...i guess my 500+hp we had was useless...LOL... trust me id love to have a nice 2000 dollar set of heads on a car but my question is why when i can spend less than 500 and still make over 500 hp and have fun ...LOL

What kind of ETs are you turning making the 500hp with these componets? What cu in?

I dunno about that whole vortecs being to much to make them work thing, I bought mine brand new with the guides machined and beter springs for 900 oh and did i mention for that 900 they came with head gaskets and head bolts, and rockers, and intake gaskets and bolts and oh yea an rpm intake, Now you find me a cheaper top end thats brand new and can take me 12.70 at 107 on a hot day and I will forever praise you.

Whoa, 12.7 is serious performance. What all have you done to your car? Must be dialed in pretty darn close.

I post my sig this time everythings in there, I still haven't ran it with the new drag radials and the lakewood drag struts and v-6 rear springs, I am hopin that on a nice cold night with my new suspention work I can hopfully get a low 12.60 or maybe a high 12.50 with would be awsome.. I am going to take the heads off and give them a mild port job and maybe a bigger cam but i'm not positive on that one but time will tell..

Nice -- I've always heard good things about the Vortecs.

I agree vortecs are good for pretty good performance, they are not a very good investment though.

If you want vortecs, get Protopline 906 replacements.

it was a 355 and i never got a chance to get it to the track i had the engine built and in the car more than 10 years ago ....its been a while since i had it and had it running..LOL..its one of those cars that you wish you still had ya know what i mean....

its a long story as to why we dont have it any more lets just say a thief had a good time getting his hands dirty under my hood one day ....

So you dyno tested it but never raced it? I've never dyno'd an engine. I've always used the track as my dyno. I would like to try some things on a chassis dyno though. More practical imo.

The engine was built and dynoed. It was one bad mofo. At that time the closest track to us was quite a distance away, so the car had to wait a while. Before we could get it there, some assclown that we grew up with tried to steal all the parts. He got caught, but we never put the engine back together, just sold it as it was.

"Extensive modifications"? You can cut the spring seats larger and clearance the guide boss/cut for different style valve seals yourself with a $50 tool from comp... Nothing else is required to run most standard street setups... Certainly that will handle the XE274, which puts a decently setup Vortec 350 well into the 12s...

Or Crane sells a set of springs/retainers for $150 that fit the stock spring seats and allieviate the clearance issues by way of the retainer design... Drop in install...

Since you can get used Vortecs for cheap they can come in very cheap for the performance.

The Pro Topline Vortecs look good on paper for the money if you're buying new, assuming they are a quality head, haven't use them myself....

**** thats awesome, how much lift can it take?

You'd have to contact Crane probably, they don't list any details about the kit anywhere I've found. I've heard several different numbers thrown around from the guys at Sallee Chevy that recommend them, from .525-.550 so I'm not aware of a good solid limit... Oh it's kit part# 10309-1 that they mainly list as for "Iron LT1 heads". Several people reportedly run these with the HOTcam with .525" lift with no problems so...

I'm planning to try this set for myself along with some 1.6 rockers on mine before too long (will only come out around .490/.500 lift with my XE262).

Also reportedly the valve seals on alot of Vortecs aren't fully seated properly which probably accounts for the varying clearance amounts people encounter. A deep well socket of the approriate size placed on the seal with a few taps with a hammer is supposed to ensure they are fully seated to get all the clearance possible...

Edit, did some digging and found this in a technical .pdf from Crane:

thanks for the good info.

So now you don't have to worry about retainer to valve guide boss clearance issues? You just drop these springs in and are good for .550" lift.?

But wouldnt you still need to change to screw in studs with lift over .490?

Still sounds like a good solution with the spring and retainers.

Alot of people are running over .490 with the standard pressed in studs, the upgraded Vortecs Scoggin Dickey and such sell don't have screw in studs unless I'm mistaken.

You could also drill and pin the studs in too I guess...

I wouldn't feel safe saying that since it doesn't directly state anything about "on vortec heads it allows for xxx lift". They could just be meaning the springs coil bind around .550... However it is definitely supposed to increase it to some point. If anyone uses them be sure to double check clearance until we get some official measurement numbers...