Sorry i spelled machine wrong in the title... anyway

I am looking to get some more out of my vortec 350 setup. It currently is a TBI motor putting out around 310 hp. I am wanting to go carb, new cam, intake, and get some head work done to my GMPP iron Vortec's. My question is what needs to be done to clear a larger cam with the heads? What price does this usually run at the local machine shop?

 

Stock vortec heads are good to about .480 lift. The box they came in should have a spec sheet....so, if you want to go more than .480 lift, you'll need to have higher rate springs and possibly mill the heads to get them to allow the higher lift. You shouldn't need to get the vortec's ported and polished...the gains are fairly minimal over stock though a larger intake such as a 2.02 may improve performance a bit. Also, make sure you get your intake port-matched to your heads and your heads port-matched to your headers. That way there is an even flow surface without any obstructions if the heads and headers don't match up just perfectly. For price...you're probably looking at a shop labor rate of $70-$90 per hour. If you can find one that does it for less, consider yourself lucky.

For an intake, I'd say the Edelbrock RPM Air-Gap intake and a Q-jet carb. the intake is a high rise intake though so I'm not sure if that fits under the stock hood. Might be able to make it fit with a drop base air cleaner. Otherwise the Edelbrock Performer is a decent upgrade from stock. Like I said earlier, I like Qjets but lots of people like holly's. The choise is really yours. You can get about the same power out of each of them though the Qjet will have slightly better economy. By going carb I am going to assume you don't need to worry about emissions where you are so I won't go into that.

 

thanks for the info, anyone else?

 

Common mods for a larger cam are getting the tops of the valve-guides and guide bosses cut down, and sometimes machining of the valvespring pockets - depending on your choice for valvesprings. A better spring might require a larger diameter pocket, or a deeper pocket for more intalled height.

If your guides are worn, then it would be a good time to get them resleeved.

Other mods depends on the shape your heads are in and what gear they have on them now. It's usually a good idea to freshen up the valve-job.

One option if your guides are worn and you will need a valve-job is to convert the heads to 8mm valves (8mm sleeves/liners) and upgrade to stock LS1 valves which are lighter and flow better. You can then use Z06 beehive style springs which go for about $50 on ebay and fit in the stock spring pockets. You can use stock LS1 retainers which are lighter and smaller, giving more clearance for higher valve lifts.
Another performance gain can be had by pocket porting your heads to better match the larger LS1 valves.

 

thanks for the great info. my question now is are the iron vortec heads worth getting machine work done? Realistically, what kind of hp numbers can you see out of them with minor head work done and a larger cam?

 

what are the casting numbers of the heads

 

they are the 062 casting number heads. the good ones from what ive read.

 

they are also know for cracking but great flowing heads what are u looking for hp

 

im right around 310-320 right now. I was looking to get around 400 out of it after doing the cam, intake, carb conversion.

 

if you go to comp cams website you can download a program called cam quest that will help you choose a cam or you can call there tech line. for my engine i called there tech line and told them i wanted 450hp and 500tq they gave there suggestion they where with in 5 hp and 10 tq on the dyno

 

very cool. how much hp do you think these heads can support?

 

Here's an excellent example.

http://www.carcraft.com/techarticles...ine/index.html

 

that is pretty much exactly what i had in mind. great find.

 

well ive been bouncing around on threads trying to figure out if i should go carbed or tpi with my vortec setup. after reading people with high flow bases cams heads and more barely turning 300hp it makes me pretty sad but reading the numbers and the amount of money they had to put into that carcraft link build i think i got something growing in my pants lol. im deffinately going carbed i dont care what kind of gas hog/O-zone destroyer ill be running 400 horses would be a good place to start ty for the link.