Tony , what valves are you going to be using in these heads . Do you find the that 1.94 size to be the perfect size , noticed the customer set in post # 1 was 1.95

 

I used a 1.950 because it was/is a shelf piece (it's a REV valve). With the MMS SB-205 heads (small bore) Im going to order/spec whatever I want. Honestly .010 in diameter is very marginal and I may end up running a 1.950 after I experiment with both but my current porting program is set-up for the 1.940.

The question that lingers is does the slight size advantage of the larger (1.950) valve offset the additional shrouding created by its closer proximity to the cylinder wall. If flow doesn't improve the 1.940 gets the nod....if flow improves, the 1.950 will be the valve I run with.

Should have the answer to this and more in the next 30 days I'm hoping!

Cheers,
Tony

 

In for the results!!!

I know Richard found the 1.95 to be a nice compromise on the flow bench for the small bore, however I don't know how in depth his testing went. I can only assume he used what was available off the shelf at the time.

I always found it odd that Everyone else wanted to push the 2 inch valve option while reaching for Max effort. How ever it always seemed to have a dead spot in the middle of the RPM range. I can only assume that maybe a result of the Valve shrouding and the air stalling.

Some one else did some testing and while they gained something like 5-10hp at the top end they lost at least 5hp in the lower RPM range. I believe around 2000 RPM

Same Heads, CNC Ported by the same porter. But one had the 1.95 intake valves and the other had the 2.00 intake valves.


My offer still stands on a 5.3L test engine. I would like to put an optimal street package together for my truck.

 

Brick,

Where are you located??

Email me when you get a chance

-Tony

 

Turbo 5.3 guys should pay attention.
Even though the common comment is "just turn up the boost"

Ron

 

I am down in Orange County but can travel up to you.

 

You have Mail!!!

 

Just stating my opinion, but I'd take the additional 5-10 up top. You won't even feel the 5hp loss at 2k RPM. Even regular street driving, you're at 2k RPM for what, not even a whole second?

Still curious about the small valves on a 205 runner though. Plenty of guys have ran the stock AFR 205 valves on 5.3's and made great power.

Will the smaller valves actually yield more?

 

Time will tell.

I had this discussion with another head porter as well. It's not about the Peak power but the efficiency throughout the powerband. On the same token you have to put a well thought out package together. Most shelf cams are not tailored to these engines in stock or modified form.

A flow bench doesn't always tell the whole store. But I have seen the stalling effect with the larger 2 inch valve on a stock 4.8/5.3L bore on a flow bench as well as a chassis Dyno, but in Fairness I believe the factory combustion chamber could be messaged to adjust for some of this.

If you look at the Heads through the cylinder from the bottom side of the block, the exhaust side valve is actually closer to the wall than the Intake valve.

I for one would like to see what Tony will put together for this market.

There are a few porters that have some packages for these engines but IMO I feel like they didn't go far enough. I realize most porters would rather spend time on other heads to put the Time and research into for the bulk of their business but I see the potential for this market.

I remember at 1 time seeing people literally throw 4.8's in the trash and giving 5.3L's away for scrap money. After people started pushing the limits of them, The prices went up and they became worth something.

 

Its actually not the older (V1) AFR 205 program I designed in 04'.....that was 205 cc with a 2.020 valve and a throat/bowl sized accordingly etc. This is a different port design and my goal is actually achieving 205 flow (very close to 300 CFM) with a smaller valve and a better overall situation on the small bore.

A 1.940 valve is still more shrouded on a 3.780 bore than a 2.020 is on a 3.900 bore which is interesting.

The nice thing for me is nothing is in stone.....I'm purchasing a small bore sleeve to install in my flow fixture and I plan to play with a few different valve sizes with the real world small bore. I wont even flow it on a 3.900.....its right to a 3.780 for any type of data collection and what will be interesting is to see what a new V2 210 flows on that bore.....my hope is to improve the flow curve with a different port design and different valve to bore relationship. Bottom line, if a 1.980 valve works better overall than a 1.940 tested on the proper bore, that's what will get the nod in my new program.

Its going to be interesting....I'm more excited about this project the closer it gets.

-Tony

 

So am I. I may go with these heads on my 5.3 instead of stepping up to a 6.0. My 5.3 has 95000 miles on it and I don't burn or loose a drop of oil. I don't have a catch can either.

 

Tony,

Care to comment on what you do with the swirl ramp?
Removing it has been an area of controversy.

I had my AFR 205's apart, and noted they don't have one. :-)

Ron

 

That was one of the "upgrades" with the V2 version of those heads. The 210 has the wing/ramp as do most of the other LS products I handled when I did the (V2) re-design. It's a key design element and you couldn't just add it to a V1 head without reshaping the rest of the port to work with it (all the shapes and contours work in harmony when things are right....disharmony when things are wrong!). It makes the design more efficient and changes some of the pressure points in key areas of flow.

I recommend you don't remove it for anyone reading that's ever considered it.....LOL

Cheers,
Tony

 

Since you're still chiming in here, for the hell of it:

I still wonder to this day, what my old car would have done with a set of 215s that were new to the market at the time.

I know my car was cammed a bit different than the norm for those heads (229/236 .631 .631 112+2) but my God did it scream. I still had EXCELLENT response and that "tip in" you always talk about.

How much difference do you think there would have been? Obviously the redesign was well worth it. I've just always wondered what the 215v2's would have done vs the original 205's I had. The cam would have remained the same though. Loved that cam.

Yeah it's off track a bit but to get Tony on here talking is always a charm.

 

The AFR210 V2 was actually the replacement for the AFR205.
the AFR215 V2 was a new product between the new 210 and the
New AFR230 V2 which replaced the AFR 225.
AFR215 was designed for the LS2 4.00" Bore but I think some have used them
On more radical 346" builds.

 

Thanks Tony.

 

Any updates tony?

 

Still sorting thru the CNC program with AFR....have alot of other work that keeps diverting some of my attention unfortunately.

Will keep you guys posted but its still weeks out before I finalize the program and share some numbers with you guys

-Tony

 

Awh man...

 

After months of excruciating waiting and agonizing over the anticipation of what could be, it appears there might be some light at the end of the tunnel in regards to the Small bore aftermarket heads.

While not 100% finalized, I hear the goal has been attained in regards to achieving flow numbers of 300 CFM for small bore applications.

Hopefully Tony will Update us when he wraps up all the little details.

With 4.8 / 5.3 engines being so cheap in comparison to the large bore blocks, Not to mention they were produced 2:1 over any other engine I can't wait to see what kind of new combo's will come out of this.