Try an interesting little trick. This has been debated on the other forum briefly.



Put you car in neutral and let the idle settle (no cheating https://www.nopistons.com/forums/pub...DIR )



Jam you foot on the gas and take it to redline.



What manifold pressure do you reach? Datalogging is the most accurate way to tell of course.



I just gave this a try. My car is not tuned at all, I've only been tuning the vacuum bars using a narrow band O2 sensor in an attempt to improve around town driveability and fuel mileage while attempting to sort out ECU glitches. (All better now!!!)



Here is what I got on stock ports and a GT42 hybrid. Some numbers from other popular turbos would be nice for comparison. Stock turbos too. Please mention any porting you have.



FYI 20.53 Kpa translates to 2.98 PSI

Well with a blown motor I could get .1psi from 0 throttle to 8k redline https://www.nopistons.com/forums/pub...O_DIR#>/11.gif

I spool at 3000 rpm with the stock ct26 and stock exhaust.

This means nothing really except maybe how shitty your car is tuned. Try taking timing away and adding a **** load of fuel. I gurantee you will see more boost.

Of course. If I wanted to get really high boost I'd just flip the anti-lag switch. https://www.nopistons.com/forums/pub...>/rolleyes.gif



That isn't the point. The point is I would like to compare different turbos to see response. My timing in the vacuum bars is within a few degrees of what most maps I see posted are. My fuel is likely only a little bit rich as I have been fiddling with it using the O2 sensor voltage readout.



People always claim this and that about boost response in different turbos, some real data would be appreciated, I think.

2.98 is pretty good stock fd's will do like 4psi in this test



mike

Nice. I couldn't remember how high it would go before.

Umm ... my car won't crank. :(

About 12 or 13 psi with a rev to 9000.



Carbureted, 62-1 with 8.5 rotors.

2.98 is pretty good stock fd's will do like 4psi in this test



mike [/quote]

you are correct sir.... sometimes a lil over https://www.nopistons.com/forums/pub...IR#>/smile.png

borked apexs

Holy shieza! In neutral? Crazy! https://www.nopistons.com/forums/pub...1047683329.gif

the wastegate opens on my car in neutral..... i love ito ports https://www.nopistons.com/forums/pub...IR#>/smile.png



so 10 psi https://www.nopistons.com/forums/pub...#>/biggrin.png

5 psi when I hit my temporary 7000rpm rev. limit and thats with a 1.22 a/r exhaust housing on the TA51. https://www.nopistons.com/forums/pub...IR#>/bigok.gif

On a free rev 15 to 17 psi.

On the two step 20 to 24psi!

Let's see some pictures of them ports!! https://www.nopistons.com/forums/pub..._DIR#>/dry.png https://www.nopistons.com/forums/pub...#>/biggrin.png

I get 7 here.

bearly 1.5psi, 60-1 .96 rear