So, whats the status on these? Do we have dyno numbers?

 

Here's the deal. When I posted the dyno numbers from a month or so ago (remember the hell that I went through for that?!?). That morning we did two pulls with the stock manifold and then we went over to Jason's place, put the MG Racing header on and then straight back to the dyno shop.

We found small but consistent gains all the way through to VTEC, where there was a nice jump of 4-5 ponies and a few pound feet. Nice. However, right below 7k, there was a trailing off of horsepower, ending up with a peak hp rating of about 7-8 below the morning baseline. Yet peak torque was higher by a couple of pound feet.

OK, here's the possible explanations that Giampiero and I have been trying to work through.


First...
I did not install the cat back for these pulls. I wanted to have an HKS Hiper and MG Racing header rating so that if case someone wanted that combination, there would be numbers to give them some idea of what to expect. I most certainly do not think that putting the cat back on would have made up much, if any difference, in that rather dramatic falling off of hp. And neither does Giampiero. So that's probably not the reason for the trailing off.

Second...
I have the Mugen ECU, which needs a littke bit of time to learn new airflow patterns. We drove straight over the to dyno shop to do the afternoon pulls and that may not have been enough time to learn the new airflow patterns. A more likely possiblity...

Third...
There was a problem with the header? I don't know. My visual inspection looked perfectly fine to me. It fit like a glove and installed in no time. I don't think this was at issue.

Where do we go from here?
Well, we are talking about which direction to take. I haven't had the time to get to the dyno shop to do another pull yet. But having driven the car enough now, the ECU has certainly learned the new patterns and has made the corrections for those new patterns. In all sincerity, I believe the next set of pulls will be very important. I simply cannot imagine that atmospheric or environmental conditions will have an impact in the nature of the way that the hp trailed off...I think it clearly has something to do with the car. So, even though the pulls have a good deal of time between them, there will be enough data to make a judgment as to why this happened...

We have been going back and forth on what to do about this. Giampiero's pulls and tests in Italy were in direct conflict with what I found, so we don't really understand why this was the case.

Just as an aside. The guys at Mugen said the stock manifold is a very nicely made piece, very very effective and they had difficulty in improving performance by theirs. The main disadvantage is the weight of the stocker, it weighs a ton. The MG Racing header is very light and made of 100% stainless steel and is significantly lighter than the stock manifold...

So, what I will do is get to the dyno shop on Monday for additional pulls to see if the ECU has made the corrections. I will report back my findings following that...

Thanks for asking! And I'm headed to Road America in a few minutes, so I won't be able to answer any more questions until later tonight. But I do welcome your ideas and suggestions. This is a strange situation and ideas are needed...!

 

Well, just out of curiousity, what were the results Giampiero got?

 

With the header and cat back, I believe there was something along the order of 6-7 peak hp increase...I don't recall the torque, but there was a nice increase...I just don't remember what the numbers were...

 

Rick, Are you using the MG exhaust and if so your impression compared to others you have heard.

 

I've installed the MG racing exhaust and also the carbon CAI as soon as i receive the headers(next week) i'll dyno the car.

Pancho

 

Did you dyno the car before you did the install? If not what are you going to compare it to?

 

Yes i put the car on the dyno 10 months ago, so i can compare it to that. But there will also be a slight gain because the car has now 10.000 km.


Pancho

 

Thanks pancho

 

I also have the exhaust and I noticed a gain below Vtec but that could be mental I have no numbers to prove it. (Dyno numbers) By the way I put on the ACT clutch @ the same time I did the exhaust. This could also added to the lower RPM gains.