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Ben006 · 10-14-2015, 02:46 PM

Good, you might be able to sell it easily

Well, I have a good and two bad news ...

The first bad news is I had to remove the plenum, to check it.
My cel went off on my way to school this morning, nothing bad, the well known P1128 and P1130 codes. I had a vacuum leak on the AOS to plenum hose.
Because the plenum is a prototype, this part is not as good as it can be (I will use another method to connect it on the next prototype).
Also, I saw that it collapses at idle, nothing bad, just 2 or 3 millimeters (3/32").
The vacuum is around 8inHg at idle and it pulls everything together (just look at the whole intake system when you step on the throttle and you'll see it moving from the variation of pressure).
That's why the by pass tube is ridged, prevent it from deformation that would cause the valve to bind.
The stock plenum is made from a material stiffer than mine, and the boss where the two parts of the molding are bonded increases its rigidity further more.

Then comes the second bad news... I have to make another prototype ! A better one.
But that takes money... and, I don't have money to spend on that at the time :/
So unless someone's willing to be a guinea pig and have a prototype for the price of a printing ...
I think the plenum is still safe to use, but I want to inspect it first (it's full of oil... from the AOS).

Then the good news !
The bigger TB does make more power !

After installing the stock plenum back in during break at school (I had it in a bag in the car for safety !), I plugged the scan tool back, and got some readings.
And it does show less flow and way less manifold pressure at WOT, which shows that the bigger TB and plenum is in fact freer flowing and have the potential for more power.

My butt dyno also noticed the low end torque was back below 4000rpm with the stock plenum, but the engine chokes past 6500rpm and had less top end.

I'll try to get more datas, but the IPD numbers are believable from what I've saw !

So now, back the computer to make a stiffer design ! (A wedge would stiffen it enough... just saying ^^)

Ben

10-14-2015, 02:46 PM	#148
Ben006 Ben-Auto-Design Join Date: Oct 2014 Location: French Riviera Posts: 827	Good, you might be able to sell it easily Well, I have a good and two bad news ... The first bad news is I had to remove the plenum, to check it. My cel went off on my way to school this morning, nothing bad, the well known P1128 and P1130 codes. I had a vacuum leak on the AOS to plenum hose. Because the plenum is a prototype, this part is not as good as it can be (I will use another method to connect it on the next prototype). Also, I saw that it collapses at idle, nothing bad, just 2 or 3 millimeters (3/32"). The vacuum is around 8inHg at idle and it pulls everything together (just look at the whole intake system when you step on the throttle and you'll see it moving from the variation of pressure). That's why the by pass tube is ridged, prevent it from deformation that would cause the valve to bind. The stock plenum is made from a material stiffer than mine, and the boss where the two parts of the molding are bonded increases its rigidity further more. Then comes the second bad news... I have to make another prototype ! A better one. But that takes money... and, I don't have money to spend on that at the time :/ So unless someone's willing to be a guinea pig and have a prototype for the price of a printing ... I think the plenum is still safe to use, but I want to inspect it first (it's full of oil... from the AOS). Then the good news ! The bigger TB does make more power ! After installing the stock plenum back in during break at school (I had it in a bag in the car for safety !), I plugged the scan tool back, and got some readings. And it does show less flow and way less manifold pressure at WOT, which shows that the bigger TB and plenum is in fact freer flowing and have the potential for more power. My butt dyno also noticed the low end torque was back below 4000rpm with the stock plenum, but the engine chokes past 6500rpm and had less top end. I'll try to get more datas, but the IPD numbers are believable from what I've saw ! So now, back the computer to make a stiffer design ! (A wedge would stiffen it enough... just saying ^^) Ben Last edited by Ben006; 10-14-2015 at 02:51 PM.