For-Real Ram Air

[Hib Halverson]

I put one of RKSport's fiberglass, replica SS hoods on my 01 last month.

A couple of days ago, I was out road testing on a run to make sure my calibration was going to work with nitrous but, before I even hit the bottle, I noted the engine was lean. So I went back to the shop.

I looking at my HPTuners' VCM Scanner logs and thinking about this for a while, I decided that the RKSport's hood cold air induction works so well that even at highways speeds its functionality is causing the engine to run lean at WOT.

I went in with VCM Editor and changed the high end of the MAF cal by 5-6% and Viola! I was back at .85-.87 Lambda.

5-6% increase in airflow is a lot. I was amazed that an SS hood could make that much difference at 60-80-mph.

With the revised calibration, I made a few test runs with my Nitrous Supply system. I'm almost ready to go back to the chassis dyno and run the nitrous there.

[WarShrike]

Re: For-Real Ram Air

Did you get to record the change in CFM from the maf tables?

I've got a WS6 hood waiting to go on mine, but it'll be feeding a turbo lol!

[Hib Halverson]

Re: For-Real Ram Air

I did not record the changes in each cell. I would have figure that from the before and after MAF tables and I don't have the time. I can tell you in general it was 5-6% increase in airflow.

Using HPT, I can generate a table of the changes. I did that for you but, on this site, I can't post images directly to a forum post on this site unless the image I have for you is already on the web, which it is not.

Email me at finspeed@netmotive.net and I'll send you the image.

Keep in mind that our induction systems are vastly different and my hood is a 'glass replica. My numbers might not be valid for your application, but...it's a starting point. You'll need to take some data as to lambda error with each hood to find out how much of a difference it makes for your car.

[CFreed11]

Re: For-Real Ram Air

The thing is though, you won't see the same results on the chassis dyno unless you have a big enough fan to replicate wind speeds at 60-80 mph on the roads. SS and WS6 hoods have always added a small amount of power, but it's unmeasurable because it requires the car to actually be moving.

[Hib Halverson]

Re: For-Real Ram Air

My testing was not done on a chassis dyno.

it was done on the road using a Innovate Motorsports wide-band. I took lambda error data and applied that to the existing MAF cal.

My shop is at sea level and the test road was in the nearby hills on a section of uphill highway. It's a great place to do WOT tests in third gear.

Testing showed the engine at high MAF frequencies was 5-6% lean. Making a 5-6% change brought the engine back to .85-.87 lambda.

When I go run on the chassis dyno in a few weeks, the fans I'll have won't force enough air to simulate highway speed so I'll either just let it run rich or change the cal.

[2.8 Bird]

Re: For-Real Ram Air

Ram Air hoods are good, but ram air kit is even better. I have a ram air hood, but it wasn't till I got the ram air kit did I really feel the difference and the filter is always dirty.