Pardon my ignorance here are we missing a picture? Which one is the STD and which one is the oversize? I assume the oversize is the one with the higher numbers on the overlay

 

Higher number is oversized

 

Correct the higher number is the Oversized Valves....

 

Nice to see a Comparison..Good Job Guys

 

We try to share what we can with everyone.

 

Just updated with the following ... .. .

4500rpm -18.89whp
5000rpm -15.46whp
5500rpm +9.02whp
6000rpm +16.76whp
6500rpm +35.71whp
7000rpm +28.48whp
7500rpm +29.49whp

 

Nice gains.

 

pretty awesome data!

 

Well done... as usual!

 

I wounder the gain is due to the new valve job or the bigger valve made the different

 

There was less ethanol percentage used with the std valves is what im reading right in the first post?

 

That's what it looks like, by 3%

 

Great work guys!

 

Wow, Nice job !!

 

Were the standard valves OEM or BC?

 

Im sorry, but I am still confused by why every dyno I see come out of there always has crazy ethanol content readings....is the fuel quality that bad out there?

besides that, those are very cool and interesting results. They basically go against everything Ive ever heard about oversize valves regarding non all out builds. Do you think these results double and so on the larger the turbo gets?

 

It depends what gas is in the tank. For proefi, to setup flex fuel you need to tune on pump gas as well as ethanol so it can blend. So when you pour in the ethanol it mixes with a little bit of the pump gas showing a lower percent ethanol.

 

New coil packs, new valve job, different E% and were calling this a apples to apples comparison? what were the ambiant temps on both days? Was it exactly the same? How many miles on the old head/valve job? Were the old and new setups leak down tested, if so what % leakage before and after?

Doesn't seem all that fair to me. I mean no doubt bigger valves help, but I don't think this proves anything. Sorry to be the one to question the testing, but I believe its worth discussing.

 

Dont take the % difference between the two as gospel, but mearly the effect it has on the powerband and the slight increase in power. The larger valves lower the velocity through the ports dropping bottom end torque a bit, but maintain flow a bit further in the rev range. You can take this data we have and draw a reasonable conclusion to the performance effects of increasing the valve size.

 

Do you think a larger intake manifold would change gains between OEM vs. Larger valves?

 

Depends on the plenum. Most of the time you will lose low to mid with a large plenum.

 

Alpha, was the head ported and bowl areas corrected for teh larger valves ? Who did the head ?

 

All we did to the head was clean up the combustion chamber, valve job and resurface. The head he purchased from a member on here had some damage in the combustion chambers.

 

Thanks for sharing the results.. very cool to see Alpha!

 

Good info. I thought I was missing out on huge gains. I can sleep now.

 

For those concerned with ethanol percentage (correct me if im wrong...):

More ethanol will burn slower, resulting in less power if the timing hasnt been changed to make use of the slower burnrate. Alpha stated that he did not adjust the timing.

As far as I read these results, if the ethanol percent was the same, it would have made a bit more power on the oversize valves then what this test is showing.

 

This is nice feedback, thanks for sharing. As far as a 3% difference in flex content, that's almost nothing, especially when you're already at 69% on the low end. And the fact that alpha states timing didn't change backs the results up as being more "apples to apples" as people are concerned about. At 69% it's likely that most flex setups will already be running 100% of the timing in your e85 timing map anyways...or at least mine would. Nonetheless, I appreciate seeing these results and we should consider being a little more appreciative as a group instead of being so quick to point out minor discrepancies. This is the shit that makes people not want to share results and info.

 

^^^^^^^ soooooo agree .... thanks for sharing the info alpha

 

Great info! Also worth noting that it's not just where the lines trace but HOW they are tracing that is interesting too.

Edit: Here's the missing torque graph until OP fixes orig post

 

Awesome work Alpha and Vic. And thank you for bringing this kind of stuff to the boards for us to see.


And I completely agree with the comment about people not being such assholes about this kind of thing. Induction was simply sharing something they thought we might all want to see. I for one love seeing this kind of stuff. It doesn't have to necessarily always be an exact scientific test in order to come to an intelligent conclusion based off the given facts. So again, Thank you to Alpha and the guys for giving back to the community.