camz28arro

iTrader: (12)

Well just thought I would share some info from this months HOT ROD magazine. The test specimen was a 408ci with 11.1 compression and a FAST 102/102 combo sitting on top with 1-7/8 ARH headers and verified 64cc chambers. The air temperature, 30* timing and air/fuel ratio were all held constant during the testing.

First they threw some stock 68cc 241 heads on the engine for a baseline and recieved 549.6hp @6200rpm where it then started to die down slowly. Below are the torque values at two points and the max torque.

Torque
3000rpm 450.0lb-ft
4000rpm 499.8lb-ft
4800rpm 517.2lb-ft

244cfm intake - 206cfm exhaust @ 0.700 lift (4.03 bore)

Next they bolted up some 64cc AFR 245 heads which measured out to 244cc. These heads made less power than the 241's till 3300rpm but then pulled very hard leaving the stockers in the dust. Peak power was 622.1hp @ 6400rpm. These heads started to roll over at 6500rpm.

Torque
3000rpm 433.0lb-ft
4000rpm 511.7lb-ft
5400rpm 558.3lb-ft

352cfm/242cfm

Test 8 was the TSP 237cc heads, these heads measured 1cc greater than the name implys but were still 6cc smaller than the AFR heads. These heads also feature a smaller intake valve than the AFR heads, 2.100 vs 2.160. The smaller runners and valves helped on bottom end power as seen below and the peak power nearly matched the AFRs at 621.3hp @ 6,700rpm and made 0.1 more ft-lbs of torque. Pretty good for $500 less!

Torque
3000rpm 442.0lb-ft
4000rpm 514.5lb-ft
5400rpm 558.4lb-ft

351cfm/244cfm

The star of the show were the expensive Mast Black Label ls3 small bore heads. Although they had giant intake runners at 257cc and 2.165 intake valves, they produced the best bottom end power in the whole test and didn't disappoint on the other end either. Power was 620.1hp @ 6600rpm. Peak torque also came in 100rpm sooner than the other two heads and was 5lb-ft stronger.

Torque
3000rpm 450.0lb-ft
4000rpm 514.3lb-ft
5300rpm 563.3lb-ft

333cfm/244cfm

Although the Mast heads had worse flow numbers and giant runners/valves, this test showed there is a lot more to choosing a set of heads. If I had to pick I would go with the bang for the buck TSP heads but the $1000 more after offset rocker LS3 heads are excellent for people with a loose buget.

Sales2@Texas-speed

iTrader: (5)

I haven't seen the article yet, but we did get a call about the results. We are pleased with the PRC head performance as compared to some of their competitor's offerings at a good bit higher price point! We've got a few new heads in the works that just weren't 't ready in time for the test too

Mike@Diablosport

iTrader: (2)

Looks like the square port vs cathedral port debate just got hot again...
(did it ever cool off ?)

camz28arro

iTrader: (12)

Also forgot cam specs, mild/agressive 239/247 0.630/.630 114

NemeSS

iTrader: (127)

i am convinced that the TSP heads are the best bang for the buck heads and reccomend them to any one who asks me.

vettenuts

iTrader: (4)

What are the chamber sizes on the other heads? You only provided 241 and AFR. Also, what was the cam?

0verkill

You left out a lot of heads from the test. The star of the show certainly wasn't the Mast LS3 Small Bore Heads, especially not for $3000. The star of the show was the TEA Ported LS6 Heads. They produced almost the same hp as the top cylinder head (which you didn't even mention) but for $1000-2000 less than everyone else.

camz28arro

iTrader: (12)

Chamber size was verified 64cc chambers as stated, a couple posts above you I also left the cam specs.

camz28arro

iTrader: (12)

I left out a lot of the cylinder heads since it isn't my publishing, I just included the three most people would be interested in IMO. To lower your high stress I included 2 more cylinder heads.

The TEA LS6 heads were the cheapest in the test at $1320 and still provided great results.The TEA heads were relatively small at 226cc intake runners and had slightly less average power and peek power than the TSPs, and Mast heads but they were nearly a match for the AFR's at half the cost. Maximum power was 618.1hp @ 6300rpm.

Torque
3000rpm 442.0lb-ft
4000rpm 515.1lb-ft
5400rpm 555.3lb-ft

330cfm/235cfm

The heads that made the most power in the test were the Procomp motorsport LS1 heads. These heads came in at only 219cc with stock sized 2.055 valves but ended up making 629.1hp @ 6600rpm. These heads also interestingly gave the worst aftermarket flow numbers in the test. Just like the biggest runner gave the most torque, the smallest runner gave the most horsepower.

Torque
3000rpm 439.0lb-ft
4000rpm 509.9lb-ft
5400rpm 557.0lb-ft

321cfm/224cfm

brngrhd

anyone have a link to the article? Id like to see where a set of wegner CNC ported heads fit in.

camz28arro

iTrader: (12)

It would be interesting to see the same test ran with a slightly larger cam. I think the TSP heads would pull away from the TEA heads if that were the case.

Wegner heads were not testing in the comparo.

brngrhd

anyone here use or dyno wegner heads? I'm getting a set since i know a guy who knows a guy and i can get them stupid cheap.....

TVWilkes

The test clearly shows the potential of the PRC aftermaket 6 bolt heads. PRC offers the best heads on the market. I can't wait until the PRC LS3 heads are ready.

vettenuts

iTrader: (4)

OK, thought the 64 was for the first head you listed. Thanks.

vettenuts

iTrader: (4)

Its in the December issue so I would imagine it is not on line yet and likely not in the magazine stores either. Those with subscriptions get them early.

01ssreda4

iTrader: (96)

I was thinking the same thing.

427

iTrader: (3)

All the heads seemed very good, I was suprised how close they all were!

Kurt

camz28arro

iTrader: (12)

I said it was the star of the show because it was the only head to make more power than the 241's in the bottom end. Price was not a factor. I wasn't talking about bang for the buck. All the heads were extremely close to each other but the square ports did better than theory believes.

camz28arro

iTrader: (12)

It should be noted though that the $1320 for the TEA heads doesn't include castings so add about $400 for good ls2/ls6 castings.

Per hp cost
TEA = $2.80
TSP = $3.54
AFR = $4.34
MAST=$4.80


The Mast and TSP heads seem to be limited by the cam though.

speedtigger

iTrader: (16)

No question for me, the TEA heads were the star of this show. In fact, after reading this article, I would be hard pressed to give any consideration to after market castings compared to the super strong showing by the CNC ported factory heads.