61 cc afr 185s clear stock pistons?

90_Red_LX

Member
Sep 29, 2003
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Asheboro, NC
I heard from a guy that built a stock shortblock combo that he ran a tfs1 cam, 61 cc afr 185s, and some intake and didn't have to make the valve reliefs bigger? Would that combo be possible ot imitate on my motor? Or would it be better to run a smaller head with a bigger cam? Losing some torque or some driveability is no problem as long as it can be a daily driver if it has to be. Just curious, as I'm h/c/i the car this winter if everything goes right. Thanks.
 
those heads should not be an issue with factory pistons with the valve relief already cut into it. The heads i believe have a factory valve angle set up so thats not the issue. Valve lift is also not an issue when it comes to valve piston clearence. I say this because at max lift the pistonm is near the bottom of the hole. The duration on the other hand is. This is how much over lap between valve being open and that is when the piston is at the top. Or atleast i believe thats the way it works.
 
Only thing is I've read several times 185's won't work with the stock valve reliefs. I'd like the bigger head for the sake of not having to upgrade in a couple years when I graduate and get some $$ rolling in, but who knows.
 
86bluecobra said:
those heads should not be an issue with factory pistons with the valve relief already cut into it. The heads i believe have a factory valve angle set up so thats not the issue. Valve lift is also not an issue when it comes to valve piston clearence. I say this because at max lift the pistonm is near the bottom of the hole. The duration on the other hand is. This is how much over lap between valve being open and that is when the piston is at the top. Or atleast i believe thats the way it works.

I do believe the factory valve angle is not the issue, but rather the larger valve size that is not supposed to clear the stock valve relief's. Now whether it doesn't clear or doesn't have proper piston to valve clearance I am unsure. If the latter you may be able to "get by" without issues. That one time however you rev a bit to high and float a valve...look out! And, using the 185's on a 302 will require you to use a BIG CAM and rev the snot out of her in an attempt to make use of the overly large heads.

http://www.fordmuscle.com/fundamentals/pistontovalve/index.shtml
 
why would you need to rev the snot out of it? i shift mine at 6200....... ive been told by many engine builders that 185s are a perfect 302 head, actually that 165s arent really worth the money that there actually a lil small..
 
yup-it clears.
im running a custom cam .525 lift, stock pistons with AFR165's-No clearance issues. Check if you have to, But its all good especially with a staock cam, really no worries.
Ant
 
monte87 said:
yup-it clears.
im running a custom cam .525 lift, stock pistons with AFR165's-No clearance issues. Check if you have to, But its all good especially with a staock cam, really no worries.
Ant

Oh ****- My bad, i thought you stated AFR165's... Sorry!
 
I may just run edelbrock rpm heads since I can get a good deal on a brand new set. There a good head and should help me out a lot, and with a 1.9 intake valve piston to valve should be less of a problem. Still researching the 185s though. Thanks for the input thus far. Anyone else?
 
95conv5.0 said:
why would you need to rev the snot out of it? i shift mine at 6200....... ive been told by many engine builders that 185s are a perfect 302 head, actually that 165s arent really worth the money that there actually a lil small..

You need to rev the snot out of it to utilize the larger flow capacity. The agressive cam is needed to aid this process and to allow more flow at higher rpms...which is where the 185's would shine on a 302.

Now, most of the 185 combos on a stock shortblock I have seen are pushing 6500+ rpm and utilizng a agressive cam. The ones that I have seen that are not typically show similar peak horsepower & torque to the people running the 165's....but the 165's typically show better low end power.

Now...when you start talking about higher compression and/or forced induction then throw the above said out the window.