C4 ram air intakes
05-17-2010, 01:08 AM
#61
Safety Car
Since we are looking for a MAP reading greater that is than at idle I would try and go as fast as legally possible with the lowest rpm possible. So go 65mph in top gear. In theory, the engine wont be breathing as hard and you will be ramming air into the intake due to the forward motion of the car.
Then for some more info, if you want to experiment, try data logging at various speeds (30mph, 50mph, etc).
The best chance you have to get a positive MAP reading compared to at idle is at a fast speed and low rpm...
Good Luck!
05-17-2010, 09:21 AM
#62
Race Director
05-17-2010, 09:26 AM
#63
Safety Car
Data logging MAP, RPM and Speed should tell the story IMHO
Data log a 1/4 mile pass would be one approach that should work??
05-17-2010, 09:33 AM
#64
Safety Car
Then one with the engine at idle.
Since we are looking for a MAP reading greater that is than at idle I would try and go as fast as legally possible with the lowest rpm possible. The best chance you have to get a positive MAP reading compared to at idle is at a fast speed and low rpm...
Good Luck!
Since we are looking for a MAP reading greater that is than at idle I would try and go as fast as legally possible with the lowest rpm possible. The best chance you have to get a positive MAP reading compared to at idle is at a fast speed and low rpm...
Good Luck!
Getting data at different speeds is the right idea but it needs to be done at WOT and with constant engine RPM in order to make comparisons..
05-17-2010, 10:30 AM
#65
Safety Car
MAP is Manifold Absolute Pressure....it is measured after the throttle body......so at idle MAP will always be very low since the incoming air is severely restricted by the nearly closed throttle body...
Getting data at different speeds is the right idea but it needs to be done at WOT and with constant engine RPM in order to make comparisons..
Getting data at different speeds is the right idea but it needs to be done at WOT and with constant engine RPM in order to make comparisons..
I it would probably be good to get data for idle anyhow. Then that number should be one of the lowest ones. Too bad there is no pressure reading in front of the throttle body as well...
05-17-2010, 07:07 PM
#66
Race Director
Thread Starter
There is a baro reading on the other side of the tb ....reread my 30 APRIL post.
05-17-2010, 07:13 PM
#67
Race Director
Thread Starter
That shouldnt be a problem. I should probably clean the filter first its been a while. So exactly what data should I get? Speed?, rpm?, gear?, cruise?, WOT?, etc..
Here's the only one I could find on my computer right now. This was when I was working out the bugs after my cam install. This may even be one where I still had a leak at the back of my intake, not sure. 65mph isnt much help. I'll try and get some new data.
Here's the only one I could find on my computer right now. This was when I was working out the bugs after my cam install. This may even be one where I still had a leak at the back of my intake, not sure. 65mph isnt much help. I'll try and get some new data.
A datalog screen shot of engine off IOT show difference between baro and MAP and then a screen shot at speed with WOT...
The info provided by your posted screen shot has enough info IE at that particular time your were at WOT...at 65mph and MAP and Baro are showing.....so its GTG...however, no positive pressure......but its a minimal drop but engine isn't reving high so who knows.....
MIke
Mike
Last edited by aboatguy; 05-17-2010 at 07:36 PM.
05-18-2010, 09:38 AM
#68
Safety Car
I have a cold air/ram-air box.... it goes down in front of the radiator and gets its air below the spoiler.....
I did a before and after track testing with it many years ago, I simply didn't see any real difference in the timeslip..... maybe a hundredths improvement at best. Plus the highway temps rose 3-4 degrees, I assume because the box was blocking a bit of the air intended for the radiator.
I do not know if my results are common or not, I chalked up the disappointment to the type of box I had. I have heard the ram-air through the license plate boxes are actually worthwhile and can show a positive improvement on the timeslip. But, that is secondhand information, I do not know this as a fact myself.....
I will pick-up a ram-air through the license plate unit in the not too distant future and do a little 3 way battle royale between the stock unit, cold air unit like I have now and the through the license plate unit. Should be interesting.....
I did a before and after track testing with it many years ago, I simply didn't see any real difference in the timeslip..... maybe a hundredths improvement at best. Plus the highway temps rose 3-4 degrees, I assume because the box was blocking a bit of the air intended for the radiator.
I do not know if my results are common or not, I chalked up the disappointment to the type of box I had. I have heard the ram-air through the license plate boxes are actually worthwhile and can show a positive improvement on the timeslip. But, that is secondhand information, I do not know this as a fact myself.....
I will pick-up a ram-air through the license plate unit in the not too distant future and do a little 3 way battle royale between the stock unit, cold air unit like I have now and the through the license plate unit. Should be interesting.....
06-28-2010, 01:30 PM
#69
Race Director
Thread Starter
...its so simple to prove whether an intake is creating less resistance...I wonder if the lack of proof means that there isn't a better than stock LT1 C4 intake...
