I know this subject has been beat pretty hard and i searched and came up with a lot of answers but i wanted to get some more straight forward questions answered. I know everyone has seen car crafts 325 horsepower 305 build up. well that is what im looking to do. i wanted to get vortec heads and at least the xe262h cam. if i get a used set of vortecs what is everything that i have to do to it to get it installed. i heard the head needs milled because of compression. would it be more worth it to buy brand new pro toplines. also what is the difference between the 062s and the 906s. is there a better cam with this setup. what is the best and cheapest way to going about with these heads.

 

I think you're on the right track with finding a used set of Vortecs. Look for the 062 casting, the 906's aren't bad just more prone to cracking. Yes you would have to mill them to get an adequate compression ratio for whatever cam you choose. The xe262 is good, and I've also heard good things about the xe268. I personally think the better route is to buy a used set of Vortecs, and modify them. Mill for compression, cut for larger sprins, mill valve guide for retainer clearance, install screw in studs, new bigger valves w/ 3 angle job, and porting would great if it is the budget. That definitely help in making power.

 

One huge advantage for the Protopline Vortecs over the GM's is the deck thickness. Milling the GM's to a 58cc chamber can be risky because the deck thickness is already considered thin. Milling that much would make it more crack prone. The Protopline decks are very meaty and are advertised to be safe at a 50cc chamber. The Protoplines also correct the deficencies of the GM's as far as performance goes. They are already drilled and tapped for studs, already have the bigger spring pads, already have the shorter guides for big valve lift, and have cooling passage improvements. I bought mine bare and assembled with Manley Streetflo valves, Comp Cam conical springs/hardware, and ARP studs for $700. I think the Scoggin-Dickey modified factory Vortecs are a little cheaper but you still have the thinner deck and inferior cooling passages. I have a set of both factories and Protoplines. They work great for their intended use. The Protops are in my IROC and the factories are in my truck.

 

since the protoplines have 2.02 1.60 valves you think it would give me considerable more power. i know the car craft build up said to use the xe262 but is there a better cam i can use with the pro toplines.

 

If you are talking the Protopline VORTECS, they do NOT have 2.02/1.60. To the best of my knowledge, that valve combination will not clear a 305 bore in ANY brand of head. The Protopline Vortecs are the same valve size as the factory Vortecs and the flow characteristics are very close. So....I would say the cam recommendation would remain the same unless your going to do something different with your car than the magazine is doing. Now do you really mean Car Craft or Chevy Highperformance? I subscribe to Chevy Highperformance and they did a build up also with Vortecs where they milled them to 58cc. I believe they got very close to 300 at the wheels. I'd have to go back and look.

 

it was an issue from car craft in 99. they got 325 horses with vortec heads and cam. i thought someone posted that the pro toplines. had 2.02 1.60s. sorry maybe i was misinformed. I know i need to get the heads milled but how much. how much should this cost. is there anything else that i need to get machined and if so how much should it cost. im talking about used vortecs

 

What compression are you looking for? Is your motor in the rebuilding stage? You could concievably not have to mill the heads at all if you can get the piston to head distance of .040" and you use a double eyebrow flat-top piston. For example, if you could get the piston .005" below deck and use a .035" compressed thickness....or if your at .010" below deck and you use a .020" shim gasket. These would get you a about 9:1 compression. Matched with the right cam, I'd think 325 hp would be easy without milling the head. Arriving at .040" is easy if your in a rebuilding stage. Not practical advice if your using a 305 with dished pistons.

 

my 305 has almost 50k on the clock. I would rather not tear into it. i was thinking since my 305 has 8.5 to 1 compression i could mill the heads like i should and also get a thinner head gasket and posibly bring compression into the 9s. is that worth it. how much to mill the heads. somewhere i heard maybe 40 a head.

 

If it were me, I would look in to the Vortec Toplines for the reasons mentioned before. Leave yourself some deck thickness for other future builds. As far as it being worth it, are you familiar with the fact that you'll need a Vortec specific intake manifold, intake bolts and gaskets? All told, with cam kit, your looking at about $1000.

 

yeah have an intake on the way already i got it for 75 dollars. now i have read the a lot of people say the toplines dont really flow as good as the gm vortecs. is this true. or is it not a significan amount to matter.

 

I don't know what started that rumour. I would say they flow probably the same, given the same valve assembly. The Vortecs come from the factory with the valves cut back (35 degrees?) at the throat. If the Protoplines are cut back also, should be no difference. Mine flow significantly better than factory Vortecs because of the Manley Streetflow valves (also cut back) and some professional port work.

I would hate to see you mill your factory Vortecs to a point where you couldn't get another build out of them. You never know, there might be a 350 in your future. If so, remember that your going to need a dished piston with the small combustion chambers.

 

btw does anyone have a copy of this article from carcraft?
im searching for this quite a while...


thanks,
nebu

 

see thats why i thought to go with cheaper vortecs because i wanted to mill them instead of buying pro toplines and milling those. i am trying to go low budget easy bolt on and i didnt want to tear into my almost 50k mile motor. that was why i wanted to know about the milling. id rather use a set of vortecs mill them and put some alluminum heads on my 350 when i build it and sell the vortecs to another 305 builder. i appreciate all of your help

 

http://www.goingfaster.com/spo/325_h...chevrolet.html this is a copy of the article.

 

@XChris1632X: i mean a scan from the original article in the magazine

nebu.

 

yeah id like to see one too

 

especially because i have a similar setup (except they used a single plane and a slightly bigger cam)
and they used a 750 double pumper and everyone says my 700 is too big....

maybe theres some info about that....

nebu.

 

Dyno runs, especially ones conducted by magazines, are typically run with big carbs as to reach the highest VE at full throttle. Unless you are constantly blasting the Autobahn, I would think a 650 would give you better driveability.