My buddy just informed me on a set of chevrolet performance vortec heads that come in either strait or angled intake bolt holes. The come in small or large port. Does everyone know about these? the reason im asking is because everyone says you need the adapter intake.

the part numbers are 25534421 for small port and 25534421 for large.

These ARE assymbled AND can run up to 521???? or around there cam lift, not the stock .475 or whatever. Ill will get a price tomarrow and maybe more info.

Sorry if this is old *** news but i wasnt ever aware there was vortecs with tbi bolt patterns.

One more thing, you can get them in center or paremiter bolt patter.


If all is right, this will allow for a $5-$600 vortec swap instead of like 800 you'd normally pay.

 

I knew edelbrock made a TBI performer for vortec if thats what your saying...

 

Im talking about Gm performance cylinder heads, that are vortec, but still have the correct intake bolt angles so you dont have to get a special intake.

 

Ahhhh that is news and is very very awsome!

 

I just got through this convo on a different forum, they require either a raised runner or vortec manifold, but you can modify the older style manifolds to make them work.

GM notes on the subject...

"Note: You must use a raised runner design intake mainifold P/N 10051103 (6 bolt mounting), or Vortec design 12366573, 12496820, 12496821, 12496822, and 12499371 (4 bolt mounting) with this head. You can use production Vortec intake gaskets P/N 12529094 (torque spec. 11 ft-lb/ 15Nm) for mounting Vortec design heads or use P/N 12497760 (torque spec. 30 ft-lb) with conventional material when using on early model raised runner or Vortec design intake manifolds, this gasket has both 6 bolt and 4 bolt Vortec attaching holes. Head casting P/N 25534351C."

"To use an older style intake you must have your old intakes runners port matched (enlarged) and use part number 12497760 in order to use the older intakes."

 

Go pick up the latest issue of CHP magazine.

They did a swap from stock Vortec heads with slight bowl and chamber polishing to the 206 cc heads and picked up 12 HP and 17 lb-ft. of TQ, and dropped .17 seconds off the 1/4 mile ET in a '66 Nova weighing 3,100 lbs.

These heads allow the use of either center bolt or perimeter bolt valve covers, are drilled for both Vortec style intakes, or traditional style, and are able to handle .530" of lift. AAMOF, the springs are LT4 springs (Part # 12551483).

They also feature screw in rocker studs, but no guide plates. They still require the use of self-aligning rocker arms.

They're available with 206cc intake runners (actually measured out to 215cc) and 185cc (I don't know what they measured out to) and come with 2.00" intake valves, 1.55" exhaust valves. They're both ~$490-$500 each assembled, ~$300-$330 each bare.

CHP used, what looks to be a Proffesional Products intake manifold with the traditional bolt pattern and used Fel-Pro Part # 1205 intake gaskets on another engine with the same heads. I can't tell if it's the same engine or not. They're different articles. I highly doubt it since I don't think they'd take the engine out of the Nova just to do a head swap.

 

So, you think the Edelbrock performer intake would mate then? it would be 100 bux cheaper than the adapter intake so i'd still be interested in doing that, because i dont want to keep the stock anymore.

 

Ok, i see what you mean now TierAngst, I compared tbi/vortec head and intake and the ports are way off. well, it was a good thought as it lasted.

 

Hey AJ, you dont happen to know the p/n for those heads do ya?

 

Sounds like he is meaning the Fast burn GM motorsports aluhead they have boltpattern for Vortec and 87-later head intakes if i dont remember wrong.
Dont have the part number though.

regards Mats

 

those heads were discussed in CHP magazine. they are iron vortec sold by S-D and modified valvetrain from what i remember. i believe they need a vortec manifold for port alignment. or possibly a traditional manifold that has the ports raised? dont think a traditional manifold will match up.

 

From what I've seen and read, you have to weld up a performer RPM intake to get enough meat to match the ports up. The RPM already has a lot of meat in this area anyway, so I doubt you could get many if any non-vortec intakes to work.

 

just buy a vortec intake, crap people. it's not worth it

 

Yeah I agree unless you want a TBI style and those cost way too much. The regular Performer Vortec is not that many bucks.

FYI I have an extra if anyone is interested. PM encouraged.........