Datalog Boost

[jonx96]

I hope I don't come off dumb with this post. I'm looking for help here and I am concerned since I bought the car used and don’t know it’s history

From what I understand from online research and watching Speedys youtube video is Boost is measured Manifold Air Pressure - Baro.

I only have a 2.85 pulley how am I making this much boost.

This would be 16.33psi DA was +800


This screenshot was -400 da but still 17.61psi on only a 2.85

 

[Hunter]

@Speedy!

 

[ACMAVRO]

for hp tuners i start log with the key in run to get the baro
1 MAP (kpa) = 0.145038 psi
then subtract the baro

looks like your map is already in psi

 

[jonx96]

for hp tuners i start log with the key in run to get the baro
1 MAP (kpa) = 0.145038 psi
then subtract the baro

looks like your map is already in psi

Yes map is already in psi.
I did not start the log with the key in run. Do you think that would make that much difference?
Baro seems to be about right.

 

[ACMAVRO]

Yes map is already in psi.
I did not start the log with the key in run. Do you think that would make that much difference?
Baro seems to be about right.

It does seem about right, mines usually about 14.4-14.8

 

[jonx96]

It does seem about right, mines usually about 14.8

All I know from the last owner was he said he raced other hellcats that were stock and beat everyone of them.
i just don’t understand why I’m making that much boost.
i just had it email tuned and the tuner ended up pulling some more timing than expected but we thought it was just bad fuel. I even put octane booster in and it wasn’t enough. I’m wondering now if it was because I was making so much more boost than expected.

 

[vortecd]

Someone else said they wee making 17 psi with just a 2.85 pulley. It was in Bulls build thread but I can't find it

 

[jonx96]

Someone else said they wee making 17 psi with just a 2.85 pulley. It was in Bulls build thread but I can't find it

Really? If you find it let me know I’d be curious maybe he will chime in and tell us about it.
@BULL

 

[vortecd]

Hpindy said this
You are correct normally a 2.85 will yield 14-15 psi on a stock hellcat with a stock supercharger at sea level .
Once you free up the inlet restriction it will raise psi . @16GoManGoHC2 has a ported supercharger with a FAS bearing plate so his inlet is about the most unrestricted you can get .

I myself picked up 1.5 psi after I ported my supercharger and added a 105mm throttle body .

 

[vortecd]

here is the thread
https://www.hellcatforum.org/threads/bulls-shyt.8306/

 

[vortecd]

Does your car have a bigger throttle body or ported blower?

 

[jonx96]

Does your car have a bigger throttle body or ported blower?

I wish I would have paid more attention when I pulled it apart over winter. Not that I’m aware of. But the cars used so maybe it was at some point. At first I was worried about a lower but i don’t believe that was it. I was talking to the wife about it this morning and said maybe it’s ported. I guess what would be the best way for me to tell if it is ported ?

 

[jonx96]

 

[jonx96]

Does your car have a bigger throttle body or ported blower?

I took those pictures but that prolly doesn’t help much.

 

[vortecd]

I took those pictures but that prolly doesn’t help much.

I would say looks stock.

 

[vortecd]

I wish I would have paid more attention when I pulled it apart over winter. Not that I’m aware of. But the cars used so maybe it was at some point. At first I was worried about a lower but i don’t believe that was it. I was talking to the wife about it this morning and said maybe it’s ported. I guess what would be the best way for me to tell if it is ported ?

you would know, much smoother like this
https://www.dusterhofftuning.com/products/jokerz-hellcat-supercharger-porting-service

 

[vortecd]

How much boost does your factory gauge show or haven't you looked at it? Mine shows 10 psi

 

[jonx96]

How much boost does your factory gauge show or haven't you looked at it? Mine shows 10 psi

I’ve seen it say 11 before making the changes. I always try to watch it but am always to focused straight ahead to look down. I’m sure I can find a passenger who would watch it tho.

 

[vortecd]

with you data logging the boost just was curious if the stock gauge was the same

 

[moparjim]

Is this the first time you ran it in DA that low?
I presume it was colder and dry air with the baro quite high.