Cylinder Head Shootout

Gee I asked this first off...Trojan did say they were going to adjust the tunes for each but I dont know if this has changed or not???

 

Doing this test, and doing it right are two completely different animals. Doing it right (optimizing the tune for each set) would require 10x the work, but it's the only real way to get accurate results.

 

Did you use velocity probes to test or just a flow bench?

The way you make it sound because A/F ratios and flow bench readings were similar they should all make the same power, which shouldn't be the case at all. I'm definitely curious to see what results you get for area under the curve.

 

Perhaps you could do this test at your expense? If I recall from your previous statements, you're the most qualified guy in the entire automotive industry to do independent testing.

 

Well I had to ask since I know you spent countless hours tuning the car with the package that was on it.Seems to me that it would make a difference.I am looking forward to the results regardless.

 

That is the funniest thing since "I gotta have more cow bell".:grin::grin::grin:

 

Nope, been there and done that with my Modular head guide. I don't have the time and I'm not interested in any of the heads being tested.

 

Any Response?

 

opcorn::whistle:opcorn:

 

Do I believe each head requires a custom tune to see true optimal results: Yes. The proof is in the pudding so to speak, and you have all the ingredients. I realize that would be a tremendous undertaking (remember, I'm not taking a shot at you, just stating MO) and it would take significantly more time and $, but again, how accurate do you want the results to be.
I disagree in that a standard tune actually does the inverse in this case by adding more variables. Certain heads will require more/less timing, more/less fuel, some heads may flow the same CFM on a flow bench but have piss poor velocity at low/mid lift, etc. etc. In this case custom tunes would eliminate such variables.

Flow bench and velocity probe testing are two different things. Unless you requested it, they only benched them.

They should be within a certain spectrum yes, however, the slightest difference between heads (ie valve seat angles) can make a HUGE difference in power but not affect A/F much if at all.

 

Holy Crap,I agree with GotStroke??!

 

Almost as funny as making 490rw from a built to the hilt 426. :imao::whistle:
Just yanking your chain Andy. I hear Ken B's been doing some tuning for you. Good choice, he's great at what he does.

 

I dont agree with the comment that different heads will want different timing.

If we were modifying combustion chambers I would agree, but since we are not, I expect that they all require the same amount of timing. GotStroke isnt really attacking Josh, but there are always ways to improve a test, but i think this test will be pretty good compared to the other tests that have been conducted and I appreciate Trojan donating his car and time and Josh donating his time and shop.

 

Built to the hilt? Hardly. That is an off the shelf 426 with off the shelf heads and cam. Until someone beats our 502rwhp, I will not be taking you seriously. lol. Ken does a great job.

 

Did you make 502rw SAE or STD?

The motor had ported heads, aftermarket cam, ported intake manifold, a forged bottom end with more C/R and full exhaust correct? What else is there?

I've known Ken for years, he's definitely an outstanding tuner.

 

Are all heads using stock valves/seats and untouched chambers? Even if they were, there can still be a notable difference in timing tolerance--even in 100% bone stock untouched heads.

Again, definitely not knocking the test, as I said previously I know it's a huge undertaking because I've done one before.

 

The 426 has 10.3 compression just like the stock motor, definitely not an all-out build. None of the heads are using stock valves, but they are untouched chambers. I would still say there isnt enough difference to justify different timing tables. Fuel might could use a change, but not timing.

 

Gotcha, more static C/R should get you over 500rw SAE for sure. I realize that the stock intake manifold was never designed to feed that many inches either (esp at high rpm) so a larger cam probably wouldn't do much for you either.

Anyone measure the difference in chamber volume with the non stock valves?

I guess we can agree to disagree on the timing issue. Just remember that casting quality can vary greatly in production cylinder heads like these. Even in 100% stock apps some heads can tolerate 2-3 degrees more timing than others--this is not a brand specific issue either.