DavidNJ

ET Performance (ETHeads) and Total Engine Airflow (TEA), both board sponsors, are both listing custom ported AFR heads. ET lists two configurations. TEA one All have similar listed intake flows; TEA claims more exhaust although those measurements are very dependent on the tubing on the exhaust port for the test. Both are near stock Z06 numbers on the intake and at or above those numbers on the exhaust.

Does anyone have more experience or knowledge about these heads? Are they really better? Interestingly, ET claims some of its big numbers on a 4.0" bore.

Thanks,

David

JZ'sTA

iTrader: (23)

David..... First off the bigger chamber AFR's are flowed on a 4.125 bore.
I dont know what you mean about the Z06 numbers unless your talking about the 06Z06 heads. If so those are also on a 4.125 bore with a different runner shape and will need a LS7 intake for the heads to work.
I personially would just stick with the out of the box AFR's. There was a great amount of time invested in geting these right.
You could pick up 10-20 cfm's but also go from a 229cc runner to a 240+cc. To me the increase in flow would equal a increase in HP and you are almost throwing 400+ dollars out the door.
Just my oponion.
On some setup's I can see where the ported AFR's might make more power, but for you avarage setup the 225's out of the box are a great buy.

Cary@Perf-Induction

iTrader: (1)

David,

We no longer carry the AFR LS1 cylinder heads. Only for the reason that we now have our own cylinder head casting that we use now. We have made many changes over the AFR. The changes we have made with our casting will make notching pistons a thing of the past for a head and cam car, we also have added .375 to the valve cover rail. As for what we used to have with the AFR, Our exhaust ports were flowed without a pipe, and Brians flow bench does not compare to ours on the exhaust side. Our intake flow comparisons are pretty equal. We have spent a lot of development time with a stock style casting and the AFR casting and just could not find enough reason to use them for the street market. In most cases we have found equal or more power with our 230 cc 5.3 head. It took a lot of creativity and testing to make a cylinder head that performed better than a stock ported head. we carry a 215 cc and a 225 cc street version of our cylinder head, and is priced equally to the AFR Heads. We have posted flow data on another thread a few days ago.

DavidNJ

Cary,

It was my understanding that the AFRs also had a heart shaped combustion chamber like the LS7, and that the heart configuration improved combustion allowing a higher compression ratio.

Are there any results with your heads on a completed engine?

Also, since these were a new design, why did you use a 2.1" intake instead of a 2.2" valve?

Thanks,

David

Cary@Perf-Induction

iTrader: (1)

David, They do have a heart shaped chamber, the ls7 is a much different chamber as our is even different. The spark plug location and quench area has just as much to do with it as the shape. We offer our heads with as small as a 2.04 and as large as a 2.220. We have different guide centerlines for the different valve sizes. That is what makes our head unique. For instance, we can make much larger flow numbers through the curve than an AFR because our valve is not shrouded by the bore, the radial distance is greater on our with a 2.08 than the AFR or stock head with a 2.02 Thus allows us to efficiently run a larger valve on a 3.900 bore.

Yes we do have heads runnning on engines, I would be glad to supply info when I have it in my hands. I know its good though.

DavidNJ

Which springs and rockers do you use? Are using standard SBC racing valves?