What would I have to do to a set of Vortec heads straight from GM to work on an 1989 L98. Are they called the L31? What is the GM part number? Basically can I just buy them and the new TPI intake and put them on? Or do they need to be redrilled? What about cam selection with the stock springs? Can the springs be upgraded and what would that cost? What do the Fastburn heads have that makes them better than the Vortecs? Higher lift springs? Will they bold on an L98 with a new intake? Anyone have the GM part number for the Fastburns?
Thanks!!

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1989 Iroc-Z L98 Original engine-58K miles!!

SLP 1 3/4 SS headers, Hooker Areochamber catback, no cat, BBK AFPR, Hypertech 160* fan switch, ported and gasket matched plenum, TB coolant bypass, relocated MAT sensor, screenless MAF sensor, K&N filters, Accel cap and rotor, Taylor SpiroPro 8mm wires, Bosch Platinum plugs, Mobil 1 Synthetic 15W50 motor oil, and more to come...
Best ET- 14.24@96.76MPH / 2.17 60ft on street tires with the crappy B/W 2.77 gears.

Homepage currently under construction: http://www.iit.edu/~wicktho/len

 

The Vortecs install just fine except for the intake manifold bolt pattern. The only thing you'll need is the SDPC intake (if they ever get it done!) or the new ram-jet from GM. I modified my stock tpi base to fit but it's a lot of work! The fast burns are larger port heads that actually don't flow as well as the vortecs except at high lift, all reports I've heard are they are more of a high rpm choice. Of course you get the benefits of aluminum with them. I was looking for low-end torque rather than top-end HP so I felt the vortecs were a better choice. Of course if you have a large budget the AFR 190's would be hard to beat.

Don't forget that either of these heads have no provisions for the stock internal egr passages so you'll have to run an external line like on some 'vettes or late model trucks or do away with the egr completely and deal with your prom codes and local emmisions laws.

I bought the SDPC remanufactured vortecs with the fierra valves, screw in studs, and upgraded springs good to .550" lift. I am pretty happy with them except for one of them stll had a bit of bead-blast media in the water jacket. The machine work was first-class though.

The Scoggin-dickey site has all the info for part #s and such.

All in all, there are just too many choices and it'll make your head hurt trying to decide which way to go Good luck!

Tim

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'88 IROC that looks suspiciously like a Jeep.
It's like a 3rd-gen with the aerodynamics of a brick but that'll go about anywhere!
Engine: 383 TPI, Vortec heads, ported plenum, runners, and highly modified base. 1.5:1 roller rockers, comp X4258HR cam.

 

How would the 64cc combustion chamber of the Vortec's effect the performance since the stock chamber is only 58cc? Would it be worth having them milled to a 58cc chamber?

 

Stock chamber size for an f-body L98 head is 64cc. The aluminum L98 corvette head is 58cc. The 305 f-body heads are 58cc also.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
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