i'm getting near the point where i'll be swapping heads on my l03. i'd originally thought about going with a set of vortecs, but i wanted heads with 58cc chambers, that were egr capable and didn't require a specialized intake. a set of pro topline vortecs with shipping woud run around $750 or so. add $150 to that for an intake and it'd be around 900 bucks to get them on my car. my plan is to use that budget of $900 and to try and get close to vortec flow numbers.

i settled on the 305 tpi head as a good starting point. while i was looking for a set of 081s, i found a set of bare world products s/r torquer 305 heads on ebay and won the auction last night.

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2450090096

i'd come across a couple of sets of 081s for between $75 and $100. the heads i bought set me back $250, but i feel the world products heads offer a much better starting point and are worth the additional expense. They should need less porting, too (hopefully), so there may be some savings there.

now i need to find a machine shop/head porting service. ideally, i'd prefer to deal with someone local. i haven't been able to find anyone, though, so i'll go wherever i need to go through the power of ups. i've done a few internet searches, and have come up pretty much empty. with the cnc machines available today, i find that surprising. all you'd have to do is get one combustion chamber perfect. then you scan it into the computer and all the other chambers are an identical match. more importantly, you now have that program saved, so you can duplicate that porting on every head with an identical combustion chamber. i figured there'd be cnc porting services all over the place. i guess the proliferation of low cost-high performance heads killed the market.

does anyone have any ideas where i can get these heads ported?

also, since i have to replace the valves anyway, would it make sense to go to 1.55 or even 1.6 on the exhaust? would the bigger exhaust valves hurt velocity?

 

update:

called world products today. they'll do a pocket port for $175, port match to the intake gaskets for an additional $125 and bowl blend the combustion chambers for $275 more. all told, it'll be $575 for (he believes) an additional 40-50 hp.

 

thats a nice price and they're c.a.r.b. legal heads.
Can you give an update. Id like to know how they work when a/b'ed to the awful swirlport heads.

thanks

 

There was an article awhile back where they did a 305 buildup and they ported their world heads. Those heads and go a long way on a 305 with some porting.

 

actually, i'm looking for that article right now. i want to send it to the guy at world products to make sure we're talking about the same thing.

you know, though, it's too bad about the egr. if that wasn't an issue, a set of fast burns would set this thing on fire. better yet, the 170 cc edelbrock etecs. they go for $579 each at summitracing.com. both of those heads will bolt on with no problem because of their 1.94 intake valves.

while i'd hoped to keep my budget for the heads at 900, there's no way. with shipping, i have 300 in the bare heads. 575 for porting + shipping to and from world products adds another 650 or so. then, i still have to buy valves, springs, etc.

still, there's no better carb legal option available that i can see that'll give me the same flow numbers. i believe if there's one place in a buildup where you should put your money, it's the heads. in the words of john lingenfelter: "The world's best cam combined with a poor set of heads will produce an engine that's a dog. But bolt on a set of great heads even with a poor cam, and that engine will still make great power."

it'll be awhile before i put these on, anyway. i have a lot more tuning on the combination as-is, then i'm going to start chip burning, then intake, then power pulleys, then 1.6 rockers. i want to get as much out of it with stock heads and cam as i can before i swap them.

i do plan one interesting thing, though. when i do get to the heads, i'm going to put them on with the stock cam at first, see what they do, then do the cam swap as the last step.

 

The edelbrocks and fast burns are sweet heads but over kill for your application. You won't even max out the potential of the world heads and you will be doing it for far less.

 

i agree on the fast burns with their 220cc runners, but at 170cc with the same awesome fast burn chamber, the e-tecs would be dead on perfect. and i'm not saving anything by going the way i'm going, either. at 579 each, you could get a set of etecs at your door for 1200 bucks.

i have 300 (with shipping) in the bare heads. 25 bucks to have them magnafluxed before i send them to world castings, 575 for the porting at world products and 100 bucks for shipping both ways puts me at a grand, and i still have to buy valves, springs, studs, etc. i'll be lucky to walk away with 1,200 in these heads.

most of the high end heads (canfield, afr, trick flow, etc) won't work well on a 305 either because of their 2.02 intake valves being too large and/or because of their 200+cc intake runners (gm fast burns). with it's 60cc combustion chamber, 170cc intake runners and 1.94 intake valves, i believe the edelbrock etec 170 may very well be the ultimate head for a 305. if only it were egr compatable ......

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