I'm a windsor jr user here and enjoy them very much. They can be ported quite a bit too since there a thick casting See sig for dyno results.

 

wow, that combo is eerily similar to mine . . .

306, 10:1
home ported Windsor Jr alums
home ported Professional products ripoff air-gap
670 street avenger with the choke horn milled off
1 5/8 longtubes, 2.5" exhaust
t5

made 300rwhp and 312rwtq


Out of the box, all the world heads are terrible. The ridges above the seat, around the guides and in the port leave a lot to clean up. They can be made to work very well though.

I have seen a very worked set of iron windsor jrs run 6.20s on the gas in a light car.

But I would second looking for used ones . . . I bought mine off ebay for $800

 

If your thinking about going with those heads ,GO with the world sr's there
there alot better with the 202 intake valves
I ran the aluminum ones and dyno'ed on motor 306rwhp,and 538rwhp with 15lbs of vortech boost ,with a F-CAM....All said and done with the totaly stock bottom end with pushing 200k on my old 302 motor.YES THERE GREAT HEADS
RAN A2 EPPING NH. 10.9@128MPH THRU THE TRAPS........
I JUST SOLD MINES A COUPLE OF MONTHS AGO FOR $850 .
AS FAR AS $800 FOR THOSE JR'S (ARE THEY PORTED? )
IF THEY ARE GO FOR IT ,THEY'LL DO YOU GREAT FOR WHAT YOUR DOING ...

 

I'm using ported and polished Jr's...Love them.

 

I've had them, and as far as I'm concerned, there are better heads on the market within your price range. They flow about what a GT40 head does unported, and by the time you put money in port work into them, you could have just bought a better head to begin with.

Ohh, and a fyi, I sold my jr's, freshened and with mild port work for $500.00, and I've seen a bunch go for about that, so $800 for used heads is kinda steep

http://forums.corral.net/forums/showthread.php?t=993187

 

Not used, I saw them in Jegs for $409 each assembled.

 

wouldn't be my choice on a stockish 5.0.
has big port intake with low flow. afr 165 has small port bigger flow. and so does edelbrock, tfs, etc....

 

I had the Jr's, GT-40 intake, E cam, long tubes, etc and ran a best ET of 11.98 @ 112. car had AC and PS at the time.

I used a dremel to cleas out all the casting flaws in the ports and to buff (not polish) the ports and chambers. Did the same to the intake lower.

I really liked mine... then I built a 408.

My recommendation would be for you to save some more money and put on the AFR 165's.....