Car is a 1990 Vert.

OK, so I got a 3 angle valve job done on the heads (replacing the gaskets after the 90K blown head gasket issue) and am doing the following;

1. Getting a ported intake and Plenum from a member here and will install that and add larger runners in the near future
2. Going to add LT1 exhaust manifolds and system
3. 1.6 roller rockers

Now the thing is there's a local builder who can do a small port and polish on the heads (113s) for somewhere around $500 bucks. I'm thinking that since I'll be keeping the stock cam that realistically I'm not going to outflow the heads even if I do nothing to them and any polishing, etc... would be a waste of money (Oddly enough the intakes match the gasket perfectly...).

The mods above are all the I will be doing to the car unless I someday stroke it, then everything would be revisited.

What's the consensus, have some light headwork done OR would I be wasting my money?

 

Maybe it's just me, but $500 for porting sounds like a lot. Between that and the cost of the valve job you're almost at the cost of something like Edelbrock heads. You could sell the 113's to make up the remainder of the difference.

Just a thought.

 

Sure, DO IT. won;t hurt anything 'cept the wallet.

With 113 heads you can only improve the way it runs. BUT, DO NOT polish beyond the injector port in the intake. That alone will loose 20hp that the port work gains...

Ok,....WHY?

because there is a thing called the boundry layer. That is the nano thin film of air thats in contact with the walls of the port. When its semi rough, like the 320 grit sandpaper, it causes fuel/air molecules to mix and stay aggitated. Fuel stays atomized....but if its slick, polished, it lets the fuel separate from the air, then wet gas enters the combustion chamber and wet gasoline does not burn anywhere near as well as gas vapor...or atomized gas.
Polishing ports that carry fuel/air was a HUGE mistake we all made in the 70s...it looked cool tho.

Port all you want. BUT, IMO, 500 is a bit much for a "small port job". Unless its a CNC port job thats flowed and on paper, proven numbers, it ain't worth $500 to do on top of other basic port matching. At that cost, you're almost able to buy a good set of performance heads used, and rebuild as needed. If it were ME, I'd get the intake port matched to the heads, open the head ports as much as possible and live with it. The single most important part of this is the port matching with gaskets as templates so there is no lip or edge anywhere. The 113s benefit from port work but there is a limit to what can be done economically. The more you do to 113s the more it cost until you have as much as new performance heads ready to bolt on. It turns into an economical issue and not a performance issue.
For $500 he should match to the intake, open the ports and do a little work on the guide hump and bowl. Beyond that to get more from a 113 it takes welding, build-up, lots of shaping and even then, you do well to get a 2.0 valve installed...Your cam will like having more air with the long tubes...keeps some low end pulling power but adds some wind to the upper end. Your LT exhaust will go well with this mild enhancement.
I've always said that there was power to be released simply by cleaning up the production castings and the mass produced intake parts.

 

A good port job will certainly make a difference even with a stock cam if its ported in the right places. So many think you have to "hog it out" (wtf is that) and carve some giant entry way grind stuff that shouldnt be and dont realize they have turned their heads into junk

A "bowl job" as some call it runs $350-500 on avg
*had to spell that one right!*

If you are getting the full port job for $500/pr you are doing really good.
That kind of work if they know what they are doing isnt cheap and is very time consuming.
Having a set of tools means nothing but if hes a full time machinist youre probably in good hands

If I ever use a cartridge roll to finish at all it wont be smoother than 60 sometimes I use none at all its just not needed.

Either way I dont think youlll notice a difference when you drive it.

Took a stock set of heads and intake base, and for kicks cartridge rolled, or "smoothed" the ports out flowed them and guess what? 0 gain, yes zero. Imo smoothing is a myth and waste if that helps you

If I had another L98 and wanted power on the cheap Id do exactly what you are. intake to the hilt, heads with stock valves some port work that imroved flow to .500 or so, springs rockers maybe exh call it a day. Should run 13s get good mileage and be reliable

 

Thanks guys! That's pretty well answered my questions. I think putting on the ported intake, Plenum, some larger tubes (when I can find a deal on them), 1.6 RR and the LT1 exhaust should get me everything I need/want. It sounds like while I might get some gains from porting the 113s from a cost viewpoint it's probably not be worth it.

I should stress this car will never see the track and where I live the nearest 4 lane high way is 30 miles away so 99% of my putting my foot in it will be below 80MPH. My goal is to get a bit more torque and upper end out of it but not end up with a high HP setup that while fast would never get used to it's potential.

I'm hoping the setup I've described gets me a little more HP and a greater amount of torque.


*had to spell that one right!*

 

Oh it definitely is.
Some bowl work and time spent on the short turn will net you good gains
for the money. Shouldnt be more than a few hundred. Its there for the taking. Heads are where the power is at

 

Oh OK. I misread your response then. Will see what the guy quotes as the actual amount. The $500 number was the assistant who answered the phone.

Thanks for taking the time to clarify.