How much power can the cast iron (fully ported w/ 2.02in 1.6ex) L98 heads make with a stock bottom end?

 

A good port job on a completely stock engine is usually worth around 30hp. You'll get more if you increase the valve lift with high ratio rockers. The reason is that porting usually gives the biggest increases at the higher valve lifts.

edit: The bigger intake valve won't help so much unless you do at least a little unshrouding in the chambers while the heads are off.

 

personally, this work to these heads are not worth it,overall if they are done correctly you will spend roughly 600.00 to do the job properly,well you are 1/2 way to a set of aluminum heads that will still out flow stock/ported..you will spend this same amount on a set of modded vortec heads but you will pay the difference buying the intake but those heads are the biggest bang for the buck..........

 

If anything 600 is underrating the cost. You can get power out of these heads, but the cost effectiveness is definitly in question. I loved how mine turned out, but the cost for me was minimal as I was working in a performance machine shop at the time. And even so if I had to do it again, I'd by aftermarket from the get go.

 

Well...I have been porting some spare 083 heads for practice and learning experience. Spent a lot of time on them. Flow tested them and everything. Definetly know a lot more about heads than when I started. Nothing like hands on experience.

They are finally finished (had to pass them off to my dad for unshrouding the valves since my Pit Crew Chief takes all my time now). He is about 120 miles away and still has them, so don't know when I will put them on; however, I put my new knowledge to use over the weekend. Got the time to take the 083 heads off my car...did some bowl blending, a little on the short side radius, and a tad of port matching...very minor porting...except the blending was a lot. These heads were pathetic looking. I forgot how bad they are at the start. Anyway, they are back on the car now, but haven't bolted down yet. No new valve job, valves, or anything, except seals. Only cost is weekend's time and $38 dollar gasket kit. That is the only change to my car. Will take to the track this weekend or next to see of that alone makes improvement on my basically stock car. Hopefully this weekend. I will post results if interested.