Would switching to AFR heads be worth it for me?

Kdubslugga

Active Member
Jun 7, 2003
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Akron, OH
My setup is below. Im thrilled with the power I made with the heads I have. They're just some old school Edelbrock Performers 1.90/1.60 valves, but I want more now. Im currently building a new 331, this time with a new Boss 302 block. There is nothing wrong with the block I have, but I know its just a beefed up stock block and if I want to make more power I better not push it any farther. So I guess basically my question is how much more power would I make If I swapped out my current heads for a set of Afr 185s with 2.02/1.60. If I can make an additional 25+ to the tires I may go for it, just wanna hear what some of you think
 
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I would, build it the way you want it the first time. I know there was a huge difference went I went from the 2.02/1.60 RPM heads from the same performers you have. I'd go to the AFR or TFS 205 heads and a more aggresive cam IMO. If your heads are in good shape you could probably fetch 600-800 bucks for them to offset the cost of the new heads
 
Yeah my heads are decent, have about 5,000 miles on em. I talked to AFR and told them my setup and goals they recommended the 185s simply because I dont race that often and i want this to be a pure street car, not a race car.
 
If I had a boss block, I'd be going for something like the TFS 205 cnc's and a cam to match. Your going to make more power, especially if you decide to overspin the s trim, or upgrade head units.
With the custom grind cam, you'll have a more street-able power than what afr might tell you over the phone.
 
If I had a boss block, I'd be going for something like the TFS 205 cnc's and a cam to match. Your going to make more power, especially if you decide to overspin the s trim, or upgrade head units.
With the custom grind cam, you'll have a more street-able power than what afr might tell you over the phone.

Well we'll see, now you got me thinkin. Does the addiction ever stop?
 
No brainer to me.... Go with the AFR or TFS 205s, and unless you intend to run race gas and crank the hell out of the boost and you need the extra piston crown thickness, then take all the cubes you can - 347, or big-bore 363. AFR 185s are good heads and will do the job, but if you're like everyone else, you'll want to push the envelope even further one day. Your block can take it, but the AFR185s could limit you.

Chris
 
There is absolutely no reason to run AFR 185s on a blown stroker. I'd grab the 205s and call it a day.

I'm a fan of the TWs, but realize that they may require a different set of valve reliefs. Not sure who is putting your motor together, but take that into consideration.
 
It's certainly worth it to goto better heads.
The least amount of boost you need to run to get the power you want the better, and the less restrictive heads will help with that.
 
I just switched from AFR 185's with 2.05/1.65 (275cfm) to AFR 205's with 2.08/1.6. Put a Super Victor intake vs a Professional Products smaller single plane intake. Nothing else changed, car runs way better up top but even seems to have more down low. I would in a heartbeat switch to the 205s again. Don’t forget you are on a 4" bore block so they claim they 330cfm on a 4.125" bore when actually they will be 300cfm at .6" lift on a 4.030 bore. I will be on the dyno in a couple of weeks...I made 417 last year. Based on track MPH I am expecting 450-460+ with 25 more cfm heads.

I would expect with your set up if the intake is properly matched and the blower does not turn into the restriction that you will pick up 75-100hp.

Scott
 
I always wanted to have a buddy who had this big garage full of dream parts that i could throw on my car just to see how it might change my combo :lol:

My dyno guy told me 185s would put me over 400hp...i just can't see those heads being THAT much better than my C9's. I know they'll be better, but i don't know about another 35hp+ at the wheels better.
 
I always wanted to have a buddy who had this big garage full of dream parts that i could throw on my car just to see how it might change my combo :lol:

My dyno guy told me 185s would put me over 400hp...i just can't see those heads being THAT much better than my C9's. I know they'll be better, but i don't know about another 35hp+ at the wheels better.

Yea, that would surprise me, too. I just don't think 185s are all they're cracked up to be, especially on a stroker. Anymore, I see 185s as a hot 302 head, not a 347. Anyway, your C9s have a pretty badass port job on them, right?

205s are the same castings as the 225s, not the 185s, so I've been told. Is that inaccurate? My understand is that the ports are 1/8" raised.

Looking at AFR's site, you can get a "nitrous port" 185 that has a raised exhaust, but the normal 185 has a stock location port. The 205 is raised.