Using a 3 bar sensor for a 2 bar OS?
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Using a 3 bar sensor for a 2 bar OS? So a buddy is doing a sloppy clone with a 4.8 and a 78/75. It's all together and come to find out he has an older PCM with only supports a 2bar OS, but he only has a 3bar sensor on hand. I was fairly certain you could make a 3bar sensor work in a 2bar OS if the sensor data was put in correct. Which we did change in the tune for the new linear and offset specs of the 3bar.
But this thing isn't running right at idle at all. He changed the map sensor back to the factory 1bar just to test it idling in the garage and it cleared right up and worked. Double checked the linear and offset and it was correct.
So...was a i wrong? Will a 3bar sensor not work right on the 2bar OS? Does the linear have to be set no higher than the OS can go or something? It's 305/10.33 for the 3 bar. If put pressure to the sensor and a 5v source and tested the linear output up to 2bar and used the findings from that for the new linear and offset would it work? Just going over all the bases I can think of.
But this thing isn't running right at idle at all. He changed the map sensor back to the factory 1bar just to test it idling in the garage and it cleared right up and worked. Double checked the linear and offset and it was correct.
So...was a i wrong? Will a 3bar sensor not work right on the 2bar OS? Does the linear have to be set no higher than the OS can go or something? It's 305/10.33 for the 3 bar. If put pressure to the sensor and a 5v source and tested the linear output up to 2bar and used the findings from that for the new linear and offset would it work? Just going over all the bases I can think of.
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What do you mean? Other than just switching it to the 2bar system and interpolating the boost area values. Most of the data in this tune I copied from another tune from an identical build.
But that's not the issue. It's a bad MAP sensor. This is 3bar MAP sensor number three from EFI-Source that has **** the bed on us. All of them failed the same way, sensor stops working and the linear goes all out of whack.
Tried another sensor and it worked fine.
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Ya I had my sensor go out at the beginning of this summer and I replaced it with another china one because it was in stock. I also bought a Delco 3 bar from a ZL1 engine and I have that sitting on the shelf just in case. I haven't bothered to hook it up yet because it doesnt plug right into my truck manifold. I have the pig tail adapter for it but I need to pull the manifold and drill it bigger for that sensor or mount it remotely.
Ah, I remember that. A little too bad it’s not plug and play. But I bet the reliability is near 100%.
I’ve tuned a few with that China sensor. I cringe! But that’s what they buy.
Think I mentioned I make my own 3 bars in the orig housing. So they are plug and play. This far, no failures. Been saving stock sensors to modify. Maybe this winter I’ll build a batch.
Cheers!
Ron
I’ve tuned a few with that China sensor. I cringe! But that’s what they buy.
Think I mentioned I make my own 3 bars in the orig housing. So they are plug and play. This far, no failures. Been saving stock sensors to modify. Maybe this winter I’ll build a batch.
Cheers!
Ron
