I just emailed a rep. from AFR and reccomended the 195cc heads(over the 180cc that I was looking at) and said that I should see a 50-90HP increase with my combo. Honestly, I find that a little hard to believe? What do you guys think the heads are worth and what improvements should I see in the 1/4? Combo is:

355 CID Holley 650 Double Pumper
9.5 CR
Home-Ported World S/R Heads 1.94/1.5 (prolly flow 210/160cfms or so)
xs268 solid cam (230/236@.050 .477/.488 Net Lift)
Dart II Dual Plane intake
1 5/8th Headers, MSD Everything, 1.5 Roller Rockers

I told the rep. I would be switching to the AFRs which will bump my compression .3 to 9.8 and I will also be adding 1.6 Roller Rockers which will put me around .506/.517 or so Lift). What do you guys think?

I'm running 13.4s@103mph now w/ 2.0 60ft time(Drivetrain is a TREMEC TKO with 3.42s and Nitto Drag Radials). I'm gonna be switching to these heads, the roller rockers, stick a 750DP on it, gonna up the gear to 3.90 or 4.10, and put on some ET STreets and hope for possibly a 11.99 with a vicious 5K clutch drop. What do you guys think?

Thanks for the help.

Nick

 

should be atleast 60..you might need bigger headers though

 

Really want to know what I think......you will be picking up the pieces of whats left of your rear end.

Seriously, I am doing a very similar swap: going to AFR 190's from World S/R Torquers without changing too much. Cam is very conservative .467 and 222 deg. I expect to go from about 350 hp to 380 -390.

Try some drag radials and launch about 2500 rpm to extend the life of your rear end.....

 

afrs are good choice, and you prolly should look into some 1 3/4 headers (slp or hooker). but yeah, if you are running a 10 bolt, 5k clutch dumps and sticky tires can make bad things happen

 

Rearend is an 8.5 10-bolt with the tubes welded so it should hold up(hopefully) The headers are also 1 5/8th long tubes if that makes a difference.

84205HO- I noticed we have a very similiar combo. When are you switching to the AFRs, I'd be real interested in what kinda new times you get. I'm not gonna know until May when I get out of school, so I got 6 months of bench racing ahead of me!

 

Definatly. My AFRs are the best thing i have ever purchased. AFRs not only flow very well when looking at peak numbers, but they really shine at lower lift. Remember your cam only passes the peak once, and the mid lift twice.

You cant go wrong with AFR! The best head avaliable(thats affordable to most) and there is also some prestige in having AFRs.

 

Sweet, bought the AFRs just for the mid lift flow........

Allgo, the 8.5 rear is a good sturdy rear if built correctly. I am in the same position with installation as you, since I live in NY. A lot of thinking over the winter, install in April/ May and best run in
Oct when the air is good.