377Z

iTrader: (1)

…the same as the S/R Torquers, if you believe their advertising. On the World Castings website, flows at 0.400” & 0.500” are listed for int/exh as the same if you look at each sheet.

I have a set of S/R’s which according to World are basically the same as Torquers but with 1.94/1.50 valves. I know you can’t bet a lot on advertised numbers and I will get my set flowed before they get installed (still deciding on whether to port them), but jeez, if that is the case then torquers would be of no benefit over S/R’s out of the box. I’ll bet its not the case though, someone there probably just got lazy when putting up the specs. Unfortunately I can’t find out as my e-mail to them did not go through (I might try later). I know its technically possible for the same castings to have the same flowrates with different size valves if the bottleneck is elsewhere in the port, but its not bloody likely to have no variation at two points of valve lift for exhaust and intake on as cast heads.

Like I said, I will get mine flowed when they are in as installed condition (need the info to help choose a cam), but its disappointing and makes me question their other fiqures.

Damon

I think you'll find that the slightly larger 2.02/1.60 combo doesn't help flow all that much more on unported versions of both heads. Your comment about the Torquers being no benefit over the S/Rs is roughly right in my expereince if you run them both untouched out of the box.

F-BIRD'88

The thing you have to keep in mind is that these heads are intended to be "Stock Replacements"

In out of the box form these heads only have modest near stock flow.

But, they really are diamonds in the rough. Like the old Camelbacks from the 60's they can be ported to great effect. 250+cfm@28 intake and 200+cfm ex. While still keeping a torquey 170+/- cc sized port.
Meanwhile they are superior castings to start with and have all the nessessary accessory bolt holes that the 60's camelbacks don't.

Get a set of 2.02x1.60 valves , a die grinder and have to it.

The combustion chamber can be improved a lot to by laying back the area right near the sparkplug like more modern high perf heads. There is lots of meat there for ya to create with.

377Z

iTrader: (1)

While perusing some more info after posting yesterday, I ran across the Chevy High Performance cylinder head article. Sure enough, the S/R torquer figures in the article match the advertised numbers exactly. Don't get me wrong, I don't expect stock replacements to be world beaters, and I know that sticking bigger valves into a set of essentially stock heads with no other changes is pretty pointless. But I'm sure you'd see some slight change, at least at low lift (Not saying it would be worth it by any means w/o some port work). My point is that their advertised numbers are even less reliable, since they obviously just took the torquer numbers from the Chevy test and used them for the Torquers AND the S/Rs.

If I knew then what I know now I wouldn't have bought these castings (even if I had gotten the 2.02/1.60s, we established in a previous thread that the castings between the torquers and the S/Rs are the same). But, I have them now and might as well use them, and the qouted fact above is definitely reasurring. Check out this cool link:

http://www.caspeed.com/488hp383.html

I would be very happy if my heads would flow like this guy's. He had them ported professionally so I doubt I could match that, but I haven't decided exactly what to do just yet (i.e. do it myself or have them done).


I'm not sure I understand--do you have any pictures of adding this feature and how it improves the heads? My heads will be going on a 383 so adding combustion chamber volume is not a bad thing (currently have flattops).

AllGoNoShow

I stumbled on a set of independent flow numbers from the S/R Heads with the smaller 1.94/1.5 valves. They only made about 205cfms intake/138 exhaust at .500 Lift. Also look at the world s/r heads in the chevy high performance My Gerneration Camaro articles and even after pocket ported them they only got 205 on the intake but like 170 on the exhaust. I imagine the bigger intake valve helps 10-15, maybe 20 cfms but I don't think the bigger valve helps the exhaust all that much.

I've seen the article you mentioned about head porting, while the intake flows as World projects, the exhaust does not even come close, I think it was only 140@.500 lift, but they respond great to porting.

I'm happy with my small valved world s/rs...in a 355 with a tiny 203/212@.050 flat tappet cam I have gone as fast as 14.3@96.5 but I know it has a 14.1-14.0 in it. I'm gonna take em off and port em this winter and hope to drop .3 or so.

F-BIRD'88

Very interesting article isn't it.

Don't worry if you don't achieve professional results by porting your own heads. Many so called professionals can't get close to that.

If you search my posts on porting 305 heads and follow the discriptions there and are willing to put in the effort you will probabily end up in the 235cfm range which is plenty for 430+ hp.

If you get David Vizard's book on building Small blocks on a Budget, these heads are covered along with the chamber mods.

Here is a pic of a Corvette L-98 aluminum head with the chamber modded as needed The S/R Torquer has the same Dshaped chamber and will respond to the chamber mods shown.

Use a old 350 shim head gasket as a guide so you don;t get carried away.

F-BIRD'88

Here is a 305 torquer head.
Now have a view of a vortec head or a AFR head and you'll see.

Take the head outside a squirt the garden hose through the intake port. You'll see the way the water wants to hug the roof and straight wall of the port then curve towards the plug as it enters the chamber.
Help it do what it naturely wants to do.

See how fat the valve guide bosses in the ports are?

major flow restriction.

377Z

iTrader: (1)

Awesome pictures, now I know exactly what you mean--thanks. That book will be the next thing I buy.

AllGoNoShow

377Z- Be sure to post your results if you do get them flow tested, I would be interested, any idea when you will have em?

F-Bird- Thanks for the pics. I'm gonna take mine off this winter and port them. Those valve guide bosses are ridiculously huge! How much can I take off them and still maintain the strength of the guide? Is the chamber mod you described a good idea even for the small valved heads?(1.94/1.5) How much cc do you think I will gain by doing that? Supposing I do a good job but retain the same valves how much do you see an improvment ET/MPH wise with me?(Its a 355 with 203/212@.050 .425/.439 cam that has gone best of 14.3@96.5mph-mphers in the 97 range when it is cold out tho)

Sorry, didn't mean to steal this post! I'd be very interested in the flow #s you get back and if you deciede to port them. From what I heard even mild bowl work without touching anything like the valve guide bosses or roofs really helps the exhaust and puts it in the 160-170 range...imagine the #s you would see if you slimmed down those guide bosses.

377Z

iTrader: (1)

Actually Allgonoshow, you're asking questions I'd also like info on, so no prob.

Odds are I will only get them flowed after porting, I considered getting them flowed before AND after, but wouldn't want to pay for it twice, sorry if I was unclear about that. It may take a while, its hard to say. I have asked a few questions about these heads in the past couple months (F-bird'88 has been one of the people here that has answered many questions, either directly or material I've viewed in searches, thanks again F'bird'88). and I thought I'd have them done by now.

When I do get this done, I will make a post about it; this way it will be yet another post of an average guy's experience with porting & other people just getting into this will realize its a good option if you don't have an excessive supply of $$$ for the latest heads. One of the reasons I appreciate this board is because I never would have considered home porting an option if it were not for some of the posts here.

AllGoNoShow

ttt

Marc 85Z28

iTrader: (3)

Would Comp's XE274 cam (.487/.490 lift 230/236 dur @ .050" 110 LSA) be too extreme for box stock S/R's with a Performer RPM and full exhaust? I plan on swapping in that cam with some AFR's soon and was curious as to how it would run with just the cam.