AFR 185s, would I have to fly-cut the pistons??

[blackened88lx]

I'm trying to put together a h/c/i package for my stock bottom end 302. I might spray it too depending on the $ situation. I was initially leaning towards twisted wedges or AFR 165s. But, I plan on going turbo with the car in a couple years when I can afford a real block. So, instead of buying heads twice, I'm contemplating going with AFR 185s now. I know they're not the best choice for what I have right now, but it might be worth it in the long run. I will run a cam in the low to mid .500 lift range with 1.6 rockers. I have read about having to fly-cut the stock pistons when running the 185s because of the 2.02" valves. Is it a definite that I will have to cut them? and if so, is it in any way possible to do this without pulling the pistons? I don't want a hack job here, and I think it would be very difficult to do this. I'm just looking for more professional opinions on what I should do.

 

[Mr. Rustypwnz]

clay the heads? Youll have to select a smaller cam to clear i believe

 

[wicked84gt350]

Well I the afr 185s are a great choice and will do very well even with 302 cubes because they are not like the typical big runner head that favor high rpm instead of low end torque. They will preform better than the trickflow throughout and a lot of other heads in the price range. I know because I have them. The only thing is the trickflow heads are like 1100 and the afr are 1400 So it may be worth getting the trickflow and port matching and a little blow work. And if you plan on runnig boost later either head will preform great so what you have to deside is the 300 bucks worth the 20-30 horsepower. And If your pistons dont have reliefs then you WILL have to flycut. If they do have them you might get by especally in the 500 lift range. BUT THERE IS NO TELLING WITH OUT MEASURING UNLESS SOMEONE HAS RUN THE SAME SETUP (same pistions, same cam, same head gasket etc...) But a thumbs up for the afr 185 would definetly do it again!!!

 

[86bluecobra]

yep no one ever likes to answer this question because what works on one car doesn't always work on another. You just have to try and measure.

 

[ls1beater4eva]

well i know with stock pictons in a 92 302 with valve rekeifs in them and i have a202 valves inthe heads im running with the tfs 1 cam and 1.6 rockers and 6.3 push rods i had to just clean up around the edges of the valve pockets where the far side of the valve came down if your going that far just take the extra time and clay the motor. Its the best thing to do instead of going on hear say

 

[blackened88lx]

yep no one ever likes to answer this question because what works on one car doesn't always work on another. You just have to try and measure.

Yeah, that's what I figured. I was just trying to get a general idea because I don't wanna drop the money on the heads, then figure out I have to pull the bottom end apart to notch the pistons. If I have to cut them, is there any way to do it in the car?

 

[cliff88145]

I am looking at the same thing but with a supercharger. I called AFR and asked if the 185's would fit on my 88 and he said not to try it unless I fly cut them. I'm just going to go with the 165's or twisted wedges. I'm think there is a way to cut them in the cylinder so someone that has do it will have to tell you. O and your BUELL is bad ass!

 

[blackened88lx]

O and your BUELL is bad ass!

Thanks
View attachment 412041

Nice intake in your avatar. Just bought one to go with the combo.

 

[gcwh02]

why not go trick flow head. Then when you take it off for the rebuild in the future, give a port job.

 

[GearHd6]

why not go trick flow head. Then when you take it off for the rebuild in the future, give a port job.

Couldnt have said it better myself.

 

[blackened88lx]

You can't really compare the 2. No amount of porting could make the trick flows run like 185s. Especially once the 185s have been ported.

 

[Grn92LX]

You can't really compare the 2. No amount of porting could make the trick flows run like 185s. Especially once the 185s have been ported.

You really aren't serious, are you?

 

[GearHd6]

You really aren't serious, are you?

Oh yes, he IS!

 

[blackened88lx]

I just want to know if I can cut the pistons in the car safely for AFR 185s.

 

[Ozrunner]

I did

I went from GT40x heads and E303 to AFR185's with XE274 and yes the pistons required an extra flycut to clear the outside section of the larger valves.

As my engine had done a few miles I didn't really want to disassemble it just to flycut the pistons a tad more as all I wanted was to test it as a 5.0.

Then I would make the decision whether to rebuild it as a 5.0 or go to a 347 so I decided to do it while they were in the block.

It was a simple excercise. I masked the complete engine up including all the ring area of each piston to be flycut when at TDC.

Used a small air grinder with an alloy cutter. It was actually easier than I thought it would be. I went slow and careful and they came up looking fine.

I then test fitted the heads and plastic checked and clearance was perfect

It might depend on how much cut your current pistons have as you can see mine already had a reasonable cut and it just needed a slight extension etc.

But you can get cutters that fit in your valve stem and you spin them with a drill etc. They're basically a valve with cutting material on the face. You would probably still need to champher the edging after etc.

It's the top reliefs in this pic that I modified

 

[bentley429]

I got a die grinder you can try out, screw AFR you need some E6's

 

[blackened88lx]

I got a die grinder you can try out, screw AFR you need some E6's

I've decided to just make some 1" spacers out of plywood to go between the heads and block, that should give me the clearance I need.

After doing some research, I retract my previous statement about trick flow heads. I didn't realize they were all 2.02" valves, and they have more potential than I thought. I'm a Chevy guy, you gotta give me a break I'm kinda leaning towards the trick flows now. I heard something a while back about AFRs having a thicker deck or something, which makes them less likely to blow head gaskets with boost Is this bs? or can someone explain this?

 

[cliff88145]

So are trick flows the way to go? I have read so many good things about AFR heads.

 

[robertdale]

both are great heads. I went with the Trickflows because You get the 202 valves and don't have to notch the pistons. Either are impressive compared to stock and other heads. With mild porting they have potential for more that a street car needs.

 

[blackened88lx]

both are great heads. I went with the Trickflows because You get the 202 valves and don't have to notch the pistons. Either are impressive compared to stock and other heads. With mild porting they have potential for more that a street car needs.

This on top of the bad things I've heard about AFR rocker studs are why I'm choosing trick flows.