Nazzz28

I need to keep my engine emission legal and am looking into all of my options. I currently have a goodwrench 350 and am looking to do a head and cam swap. I would like around 300-350 hp with a nice broad torque curve, since the car is driven primarily on the street. I was looking at using the comp XE 262 cam to help maintain nice driveability. I looked at the sportman 2 heads but think the 200cc runners will be too big for what I want, since my car rarely goes over 5000-5500rpm. I think the 67cc S/R torquers with their 170cc runners will give me the low end torquer that I want and put the power band where I need it. I am just wondering if anyone knows what I could expect out of these heads and if they will yield the power I want. I figure any heads have to be better than the 993 castings that come on this engine.

five7kid

iTrader: (14)

They would be a nice improvement over the Goodwrench heads.

For best results, you should figure on doing basic porting work, at least clean up the bowls and guide protrusion into the flow path. Otherwise, they'll fit the bill.

BLUETA

I have them on my 406 built for all torque using rpm up to 4500. They perform well and my mileage is up 2 mpg over what I got with the original 305. Be sure to open up your intake. Just taking the air filter out of the canister and putting it into the open on mine made the last 500 rpm really wake up. A little porting never hurt either.

AllGoNoShow

If you go to compcams website and look around they have dyno sheets of the xe262 with the s/r heads. Suprisingly that cam actually made slightly more power then the xe268(most be a little too big for those heads stock). I think it was in the 340HP range.

Nazzz28

Thanks for all of the help, I think I am going with the s/r torquer heads with the 67cc chambers. I want to run a comp cams XE 262 cam but am wondering a couple of things. what roller tip rockers should I use? Originally, I was going to use the comp cams magnum 1.52:1 rockers. I would like to know how this will effect the power curve and if I should stick to a 1.5:1 rocker or go with them and the 256 cam instead.

Allgonoshow - thanks for letting me know about those dyno sheets. I figure with the smaller chambers my compression ratio should be about 9:1, which is close to the one shown. If I could get those numbers I would be really happy.

five7kid

iTrader: (14)

The Comp Magnums don't affect the power curve significantly with the 1.52:1 vs. 1.5:1. If you read their marketing info, what they're basically saying is their rockers maintain that ratio better than the typical stamped. They won't be quite as good as a full roller rocker, though.

The heads would be better able to handle the larger cam with the porting I mentioned earlier.

five7kid

iTrader: (14)

FWIW, the Comp dyno tests used Dart S/R heads, which were the earlier version of the Worlds (Dart did the casting for World back then, they've since gone their separate ways). I don't know if there were any significant differences between the Dart S/R's and the current World S/R Toquers, but they aren't exactly the "same" head.

AllGoNoShow

I have the Dart S/R Heads and I swear they are the exact same design. Every picture I have seen of the ports and bowls look identical...could be subtle differences but I doubt it.

I know you have the world s/r heads and ported them so take a look at the first two pics of my Dart s/r heads in here : http://community.webshots.com/album/110849581wiVloK



Those other pictures are of the heads in various stages of being ported...I still haven't put up the final pictures but am going to wait until I get drag strip results.

PS-Nazzz28- I have a 355 with a 203/212@.50 economy cam with untouched Dart s/r heads(with the smaller 1.94 /1.5 valves) and run low 14s at 96-97mph). I'm happy..if I hooked it would be in the 13s no sweat.

The Chad

To remain smog legal [emissions legal] with the S/R torquer heads the heat crossover passage must be drilled thus activating egr.

five7kid

iTrader: (14)

A little hard to tell from those pics. Besides, it's been almost 3 years since I did mine, and memory is fading...

World has both what they call "S/R" heads, with 1.94/1.50 valves, and "S/R Torquer", with 2.02/1.60 valves. So, the Dart S/R's may be like the World S/R Torquers. I'll agree they do look very similar.

Not true with either the S/R's I got back in '97, or the S/R Torquer 305's I got in '01. The passage looked just like stock.

I believe it is true for the Sportsman II's, however.

Nazzz28

Thanks again for all of the info guys.

All I am looking for is low 14 - high 13. Their are alot of spoiled import owners in this area and I am getting sick of just being able to barely pull away from them. I don't really race on the street, but it would be nice to know that I could leave them in the dust if I wanted to. Not to mention I just want my car to be faster to match the looks when I am done this spring.

Allgonoshow - nice car. My brother in law has a red 79 z28 that we have done some bolt on stuff too. I think he hangs out alot on www.Nastyz28.com or something like that.

titchener

(discussion regarding World S/R Torquer heads)

BlueTA, I know this was a pretty old thread, but I'm planning out the build of a "reasonable gas mileage" 383 to replace my 305, and your statement that you got better gas mileage with a 383 with the S/R Torquer heads caught my attention as I'm looking seriously at those heads as I think they will pass a visual smog inspection (I'm in California).

Can you tell me what cam you were running in the 406 or what the cam specs were? What gas mileage did you end up getting?

Right now the current plan is a 383 with the S/R Torquer heads, set up around 9.5 to 1 with the RamJet/HT383 cam, it makes impressive torque and is not too bad on power, the HT383 motor makes pretty good power up to 5000 RPM.

Thanks,

Paul T.

327_TPI_77_Maro

iTrader: (8)

\oh man old thread, never mind