r71

iTrader: (3)

Will the stock 2 Bar Map sensor limit my boost to 15psi, even if I turn it up above that on my boost controller?

Over the weekend, I could not get above 15 psi no matter what I set the boost controller up to. Do I need a 3 bar MAP sensor?

Mahjik

iTrader: (1)

What mods do you have on your car?

You might not have the airflow to get above 15 PSI.

r71

iTrader: (3)

Mods.

Mahjik

iTrader: (1)

To answer your question, I don't believe 15 PSI is the limit of the stock MAP sensor. I've read of people hitting at least 17 PSI on the stock MAP sensor before needing to upgrade:

https://www.rx7club.com/forum/showth...hreadid=152260

https://www.rx7club.com/forum/showth...hreadid=152271

SPOautos

The stock map sensor will display up to 1.15 on the PFC. This comes to 16.35 on the PFC but on a mechanical gauge your probably going to see more like 18psi.

If your only getting up to 15 you either have a bottle neck somewhere or your wg is wide open.

As a test you could always throw on a manual boost controller and see if you can get the boost up, that will tell you if the problem is in your controller or something else.

STEPHEN

Tim Benton

iTrader: (1)

Good point Stephen, the stock one goes up to about 17 psi. I couldn't view your mods list since I'm at work got to save time and not view sigs and such.
How did the hitman do for ya? What HP at what boost and a/f ratios?

Tim

r71

iTrader: (3)

At 14 - 15 psi, he gave me another 22 ponies. on stock turbo, stock motor, I'm getting 346 at the rear and ~300 ft-lb of flat torque curve. It feels better over all. Only problem I'm having is the transition with the 1600cc injectors. He couldn't tune out the hesitation. On slow throttle, it's bearly noticeable, but at full throttle, it hesitates real bad at ~3900rpm. He says PFC is not designed for the 1600cc injectors. No one seems to provide any answeres to solve this. I know it's got to be the injectors because I had no hesitation with the stock. It was the only mod performed before tuning. I don't know wat a/f he used. I know he worked his way from 14 down to 11. Dave recorded the whole thing on video.

Tim Benton

iTrader: (1)

Did you input the 1600 into the pfc by using the datalogit? The commander only lets you put in 1500 cc. If it was 1500 cc, but its really 1600 cc injectors, then the car would be rich as a pig and Matt would have had to back fuel. And if the 1600 isn't in the PFC via the fc edit input, then I doubt the lag time is set correctly as well and the transition timing of the injector overlap as mentioned in the PFC forum section.


See ya soon,
Tim

r71

iTrader: (3)

Before I went up there, I changed the pfc to 1600 using my datalogit. Matt changed it to 1380 because he's wideband showed that the injectors were working like 1300's. Everyone at dynolab visually checked the injectors and they are the 1600's. Then again I got the kit from Jason who sold me a SX fuel regulator that had the wrong AN fittings that were bottoming out and blocking flow. I had to cut the AN fitting to create flow. That costed us at least 3 hours. Maybe I got a bad batch, maybe the 10 ohm, 10watt resistors are not doing what they are suppose to do. I got his maps saved so I'll play around with the settings to see if the hesitation goes away.

If your reading this Jason, please double check the fittings you supply with the regulator.

Tim Benton

iTrader: (1)

Wow, that sounds like quite a headache trying to figure that out. Hopefully you can get some answers dealing with the actual injectors since I'd hate to have to yank them out and send them to RC to verify their flow rate.

Tim

SPOautos

If you want to run 1600's you really need to tune it with the Datalogit and not the commander. There is no way to make them smooth with the commander, I dont know why he wouldnt use a Datalogit, that just doesnt make any sense to me. There is something really wierd about it. He prob just isnt familiar with the software.

Anyway, what I would do at this point is find a map with your injector setup for twins on the Datalogit user group and look at all thier injector settings and see how they compare to yours. Also, look at the fuel map settings to make sure yours is similar to thiers. He might have been using the 1380 he put in there as a way to change the mixture then when you input 1600 its going to throw the fuel all off so you need to be very carefull. I know it sounds like a lot of **** but its what your going to have to do if you want to get the injector staging right. He shouldnt have tried to tune it the way he did....especially if there was a Datalogit there.

I just dont understand why he didnt just use your Datalogit and set the injectors up properly.

STEPHEN