Infor about the 3.1L MPFI v6, and using MegaSquirt 3 on it

Want to know how to get more out of your Beretta? Or have a mod you would like to share?
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Asylum
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Re: Infor about the 3.1L MPFI v6, and using MegaSquirt 3 on

Post by Asylum »

That is how it was explained to me when GM started marketing the SFI designation, however they discovered the ECU couldn't keep up with SFI at higher RPM and allowed it to revert to MPFI.

SFI at idle also probably helped emissions as well.

In any event it really shouldn't be a major factor in tuning, and the injectors themselves really can't tell the difference. They just fire when told to/grounded.

:beer:


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Re: Infor about the 3.1L MPFI v6, and using MegaSquirt 3 on

Post by Rettax3 »

...And without the hi-res 24x CKP or the cam sensor, the Monte PCM will throw a code and run MPFI, I've never heard of them slipping into a limp-home mode for that, although I have seen one or two engines that died with those sensors unplugged (which they shouldn't, so there was/were probably other issues too). Considering that you want to put in other upgrades later, I would just go OBD2 -it is a more dynamic system (just meaning it can handle continuing changes better), mostly because you don't need to keep burning chips for it. You just reprogram and go again. With the MAF on it, it will adapt better to small displacement changes too, like 3.4 ->3.1 or 3.1->3.4 or 3.1->3.5, etc. Overall, OBD1 and OBD2 both do have their advantages and disadvantages, but for what you are doing it sounds like OBD2 might be the better approach. Jon, does the DHP handle the '02 Monte PCM, I don't recall? I am going to have to get back into research-mode on this myself and start downloading as much of the BIN files etc as I can...


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
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Re: Infor about the 3.1L MPFI v6, and using MegaSquirt 3 on

Post by 3X00-Modified »

Yes it handles the 02 Monte PCM.


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Re: Infor about the 3.1L MPFI v6, and using MegaSquirt 3 on

Post by Alxsmt »

looks like im a little late. but I highly suggest MS. I had the ostrich for years.. could never get it right, always had tons of random bs issues. I went with MS2, and I will NEVER go back. makes life a lot easier.

you can even control boost with a boost vs rpm table, basically add boost wherever you want it in any given RPM range. you need a few extra parts to make it work but why not?


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88 Beretta CL - your average grandma car.. Ls1 swap in progress
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Re: Infor about the 3.1L MPFI v6, and using MegaSquirt 3 on

Post by Rettax3 »

Alxsmt wrote:looks like im a little late. but I highly suggest MS. I had the ostrich for years.. could never get it right, always had tons of random bs issues. I went with MS2, and I will NEVER go back. makes life a lot easier.
...So you want to unload your old Ostrich stuff cheap? :wink:


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
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Re: Infor about the 3.1L MPFI v6, and using MegaSquirt 3 on

Post by Alxsmt »

I sold it about a year ago actually


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88 Beretta CL - your average grandma car.. Ls1 swap in progress
77 Celica - needs an engine swap
96 Geo - 1.0L, Cam, 3 angle, magnaflow, Koni, coilovers.
86 Subi - Supercharged @7psi
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