I recently read a artical about using late model vortec cylinder heads on older block castings. They gave flow data comparing 4 differend chevy cylinder heads. The vortechs out flowed an 80's bow tie 2.02 cylinder head and they mentioned what had to be done to make them fit. I know they bolt right on and you need a new intake manifold and some other things. I was wondering if anyone had or knew where to get more info on this subject. Also what is the best vortech head to get and what would be the casting #'s to look for. Thanks!

:)

 

First, the vortec heads are lift-challenged. They require modification to accomodate a cam beyond .470 lift. Also, given the price $450 + intake + clearancing to accomodate say .500 lift cams, I'd go instead with a good 180-195cc intake runner head from AFR, Dart or Brodix. You will be further ahead in the long run. Also, vortec has a very small combusion chamber, 64cc I think. May impose compression issues (detonation). I chose the Dart Iron Eagle head (180cc intake runners, 72cc combustion chamber). $850 plus delivery, fully assembled and accomodate up to .525 (or was it .550?) lift without clearance issues). The tech rep also claimed they would accomodate Pro Magnum rockers without stud modifications.

 

I called around and I get a used set of the heads for around 250-300. Then about another 100 probably for the intake. I'm not positive but im pretty sure my cam has less than .470 lift. I know the Dart heads would be better but I'm trying to keep things cheap. How much more do the Dart heads flow over vortech ones? Can you modify the guides to make more clearance for higher lift? Or is it plane ol not worth it? :rolleyes: :smash:

 

If you are going to pay $300. for a set , buy them new. Intakes for vortex are usually around $200.

 

What year model is your Vette? Are emissions compliance an issue for you in your area? (No EGR provisions on Vortec heads)

Vortec heads are great if they suit your needs. There are some guys here on the forum using them. The $699 Vortec Head Kit from Scoggin-Dickey is a neat package if you don't already have some of the parts needed. http://www.sdpc2000.com/cart.asp?act...d=277&pid=1120

Have you read the "Chevy High Performance Goodwrench Quest" article? Part IV Has some highlights regarding the GMPP Vortec heads.
http://personal.clt.bellsouth.net/cl...in/chp/chp.htm

Along the lines of what TedH said, some of the potential downside to Vortec cylinder heads are: . . .
-Stock valve springs are considered wimpy (may have to spend money for better springs with higher lift cams)
-Machine work required on valve guides if your cam exceeds "0.4??" of lift (could interfere with future cam upgrade)
-Require self-aligning rocker arms. (not a big deal)
-Pressed in rocker studs (not a big deal in most cases)
-Vortec specific intake required. (cost slightly more than non-vortec version)
-No EGR provision (if needed for passing emissions test in your area)
-Requires center bolt valve covers (cost a little more but seal better than the old style)

I think that they are great when used in moderation. I almost used a set for my car but finally decided not to mainly due to lack of EGR provisions needed to pass Texas visual inspection.

 

I've been running with vortec heads for about 2 years. I found a machine shop at a show that sells them rebuilt. I got the heads with upgraded springs, three angle valve job, self aligning rocker arms and valve covers for $400.00/pair. I was planning to upgrade the intake manifold anyway, so that was not really an unplanned expense.

I had my car dynoed with my old 1970 350ci camaro (with well over 100,000 miles) engine in need of a bottom end rebuild and still pulled 251hp and 310lb-ft of torque at the rear wheels. Thats with a mismatched cam as well. I'm very happy with their power.

Regards,

Jim

 

Follow up question to MIKER or anyone..... is anyone running Vortec heads with some work done to them and a nice healthy cam?? The latest CHP gave me an idea (p.58)...... The GMPP HT383 comes with Vortec heads and pumps out 325hp/415torque..... put in HOT cam kit (HOT cam, 1.6RRs, springs, etc) and ?? (I haven't had a chance to do Desktop dyno on this combo yet) It's got to be over 400/400 with potential for more with some porting. Other than machine work on the Vortec heads, what else would be required? Seems like everyone's doing a ZZ4, so I want something different.

http://www.sdpc2000.com/cart.asp?act...id=120&pid=465


[Modified by Scooter70, 6:25 PM 2/14/2002]

 

I have the vortec heads in my 81 Z28 with the HOT cam. It dyno'd at 407hp and 410ft/lb of torque. I bought it as a crate engine from scoggins-dickey. No port work was done to the heads. This engine is the base 330hp 350. With the vortec heads and HOT cam it dyno'd at above numbers. Very happy with it.