I was thinking about doing a head change and putting S/R Torquer 305's on my 5.7 liter auto 91z28 1LE. I think the chamber volume is about58 cc's. How much power gain you think i will get and do they have egr provision and are they smog legal. What do you guys think i should go with these s/r torquer heads are some other heads. I got to pass smog and i don't have alot of money to spend. thanks.

 

I would go with the 2.02/1.6 64cc S/R Torquers if you want more power.

 

The torquer 305 may hurt your HP rating. I would go with a set of 2.02 heads (Sportsman 2) would be nice or like Iroc22 stated. You can always mill the heads to raise your C/R ratio.


Brian

 

I would definitely go with the 67cc chamber torquers over the 305 heads. The 305 heads are designed very specifically for that engine and it's limitations (small chamber, 1.94 int valves, etc.). Meanwhile, the larger chamber heads have bigger valves and flow more all while retaining all emissions crap (hence S/R). I don't think they come in 64cc versions, which is what is stock for your engine, but you can get them milled down a bit to bump it back up. The tiny 58cc 305 heads will raise the compression ratio to a point (about 10:1) that is very questionable on pump gas with iron heads.

DG

 

GET THE MAY 2002 ISSUE OF CHEVY HIPERFORMANCE MAGAZINE AND READ THE ARTICLE ON PORTING YOUR HEADS. THEY ARE DOING A WORLD S/R TORQUER AND HAVE THE FLOW NUMBERS BEFORE AND AFTER. ALSO GO TO THEIR WEBSITE TO SEE FLOW NUMBERS FOR OTHER HEADS. ( CHEVYHIP0ERFORMANCE.COM ).