Opinons on Replacement Heads

[Guest 77vegasz]

I investigated what I thought was a leaking head gasket to find that one of my 461 camel hump heads has a crack.

 

I am running a 327 with the 350 hp 327 cam, 220 duration at .050 with .447 lift on both intake and exhaust. The power band for this cam 2000-6000 rpm. I was thinking of going with Vortec heads and intake.

 

Does anyone who is more knowledgeable have an opinon on this choice? Would aftermarket stock style head like Edelbrock performers be a better combination with this lower end?

 

All Input is appreciated.

 

Jon

[grumpyvette]

the vortec head swap requires more than just the intake and heads, read this add carefully

http://www.sallee-chevrolet.com/Cylinder_Heads/Vortec.html

youll need new center bolt valve covers and rocker arms also, while the vortec heads will work very nicely on a 327 by the time you get everthing necessary youll be very close to the price of better aftermarket heads, vortecs have pressed in rocker studs, limited valve spring clearances and smaller valves than the aluminum trickflow heads that are significantly better at producing high rpm power, remember vortecs are truck heads ment to produce maximun torque not hp

 

http://store.summitracing.com/partdetail.asp?part=NAL%2DVORTECZZ5

$369 x 2 =$738 for heads

http://store.summitracing.com/partdetail.asp?part=EDL%2D7116

$175 for intake

rockers and valve covers easily cost $200 plus so vortecs true cost is over $1000 installed

 

 

I would strongly suggest the TRICKFLOW ALUMINUM heads as a good choice

 

http://store.summitracing.com/partdetail.asp?part=TFS%2D30400001

 

at $969 they are a good deal,and you can use standard valve covers,intakes and rockers

the dart iron eagles are a reasonable choice but for the differance in cost I think youll see the trickflows are a better deal

http://store.summitracing.com/partdetail.asp?part=DRT%2D10121111

[Guest 77vegasz]

Thanks for the info. I didn't realize I would need rockers as well, or that the covers were so expensive. I will check out the alternatives you listed.

 

I do hate to have to trash my roller rockers and intake!

 

Jon

[Pyro]

You should keep your head selection under 200cc. 170 to 180cc would be better for a street driven 327. And you should get the 64cc combustion chamber to maintain your compression. The AFR head is one of the best heads out there but cost a little more. Iron eagle heads and World Product Sportsman heads are a good deal and are about the same. Trickflows are nice but I think they require longer push rods and need washers under the head bolts.

 

In general, aluminum heads run better at higher compression ratios and will make even less power compared to a similar flowing iron head at lower compression ratios (less than 9.5). Finally, most aftermarket cylinder heads require longer head bolts.

 

I think you will also make more power with a more modern camshaft. The 350hp GM cam is pretty much a dog. It has very slow ramps and not much lift. It bleeds off cylinder pressure which kills power. Get an extreme energy Comp Cam or something like that.

[SpeedRacer]

I’ll go with Grumpy on this one since I use TrickFlow aluminum heads on my 327 and love them.

 

http://www.cardomain.com/member_pages/view_page.pl?page_id=236622

 

I used their 23 degree heads and the old 365HP 327 cam which uses solid lifters. Trickflow listed them as having 64cc chambers. Yes, you need to use hard washer under the bolts because you will gall the aluminum. On cast iron heads the hard washers help to even out the torque so it's a good idea to use them with all heads. You don't have to buy a set because Trickflow supplied them with the heads. I did not have to change anything else - head bolts, pushrods, valve covers, intake manifold, etc.

 

http://www.trickflow.com/product/prfeature_index.htm

[getZ]

Hi.

 

I'm new to the group, but a long time chevy fan. There's a lot of very good information in this form.

 

I still think vortec heads a great bang for the buck if you don't get everything brand new. A lot of circle track guys run them.

 

The vortec heads listed by summit above are the heads modified for higher lift cams (above .480). With the cam you are running, you can order the cheaper heads (part #NAL-12558060 $519.00 per pair) good for up to .480 lift assuming you are going to used 1.5 ratio rockers.

 

Something to watch for when swapping heads is the combustion chamber volume as this will change your compression ratio. The fuelie head you mentioned probably has 64cc combustion chamber volume and the vortec head is the same so this won't make a difference in this case. Some of the later heads mentioned are a bit bigger. Lowering the compression ratio will lose a bit of horsepower.

 

As far as a manifold selection, I have a high rise vortec manifold I can sell for 20 bucks. It's been port matched to another head so I don't know how well it will work or if it will clear your hood.

 

As for the valve covers and rockers you can find them in a boneyard for cheap as they were used on late model gm trucks until the LS series engines came out. Corvette valve covers looks sharp, but need a bit of trimming on the inside if you upgrade to roller rockers.