Hondata

Hello all, new to the tuning thing, so help would be awesome here.
88 prelude, b20a, s300

I bought a map off ebay that gave the voltage/pressure readings, and I put this info into a calculator for the scalar and offset info. Using this info got me a -0.9 before starting the car and seemed off (in my limited knowledge).
Asked a buddy what I should do, and he said to use a vacuum pump and watch the pressure readings in hondata and adjust the scalar/offset so the reading on the gauge matches hondata.
I did this and it helped as the scalar I got from the calculator made the readings way off. Was getting an increasing divination the higher the vacuum. I got it pretty damn close to a 1:1 ratio, so I believe the scalar is correct. But now my engine-off pressure is 0.2.
Since using the vacuum gauge seemed to work, atleast scalar wise, I attempted to start the car, to see if it would even start. It ran only with adding some throttle, but the main issue is that at aprox 1000rpm, my map is reading -2.5 where I would expect it to be like -20ish?
Current scalar 660, offset -10

Question
Is there a guide to set a map sensor like this? This isn't one of the preselected options unfortunately, though I'll purchase one of needed.
Any ideas/tricks here? If this is sticky"ed somewhere, i apologize, I just signed up just now.
Thanks! Looking forward to speaking with y'all and learning this skill.

Have you contacted the manufacturer of the MAP sensor. What kind of MAP sensor is it claimed to be?

It's supposed to be a gm style map sensor. I haven't spoken to who I bought it from, but it's a ebay no name special. That's why I'm saying if I need to buy a name brand, I will.

We sell a plug and play sensor: https://www.hondata.com/products/access ... ap-bseries

While I would have no issue buying this to get it running, isn't this the map style that plugs into the TB? With a port on the bottom of the sensor? I don't know much about hondas at all, but I believe my b20a5 map was originally located in a vacuum box mounted on the firewall, and I wouldn't be able to use this style? That's why the gm style sensor was installed I believe. Thanks for the help

Do you know what the rating of your MAP sensor is?

3 bar

Have you tried the presets for the 3bar sensors in the software?

I have messed around with them a bit, but don't believe I've tried to start the car with them. Whats the criteria for a decent enough selection? What should the engine off pressure look like? Do I kinda feel like the sensor scalar is correct, but the offset is way off? So could i minus the offset so that it has a more correct baseline pressure, then when the engine is actually running, the map will read the correct columns? For example, I read a random post saying engine off, three pressure should be around -26?

Any ideas here? I'm guessing I should just get a better map sensor?

So I've been playing with the different map options, and doesn't matter what I do, my map will never read much below boost. Hopefully the picture attaches, but I only ever datalog on the top right of the fuel map, never really getting below -4. Seems that if I were to add throttle more, the vacuum would decrease but I don't want to push the motor when it's not running correctly. Any ideas here?

Personally, I would just buy a brand-name MAP sensor with known scaling.