Ported intakes and OBD 1.5

[Purple pit]

As some of you know I have a 95 Beretta base, so I have OBD 1.5. I plan to get some ported intakes from Ben, but I'm not sure how much the computer will tolerate.

Can I run stage 2?

Just a little back ground: I do have 99 Venture van injectors on right now.

[robertisaar]

it's not 1.5(it's pure OBD1) and the computer can be tuned.

that being said, they'll work, but they won't be optimal without tuning.

[Purple pit]

Lets see if I understand this. OBD1 is really OBD .5 and OBD 1.5 is OBD1?

Everything I do is a bit strange lol. No really there is just a few of factors. I would like to have the stage 2's for a later engine swap. I also need some intakes that are tapped for my stock coolant by-pass tube right now.
So there is not going to be any leaning out at WOT?

[robertisaar]

pretty much anything 82-95 from GM is OBD1, with VERY few exceptions. the 93-95 3100 is not one of them.

it will lean out(more airflow will do that), but the amount it gets leaned out is something i can't comment on. Ben or someone running the stage 2s will have to comment on that.

[Purple pit]

Ok I'll wait to see what Ben has to say.
Looks like I may end up going with stage one, damn.
Thanks for the replys.

[SappySE107]

Ported manifolds aren't going to cause a problem, run lean, etc. You can run ported manifolds, heads, 56mm TB, and a street cam on the stock computer if you wanted. Not sure about those injectors though.

"OBD-1.5

OBD 1.5 refers to a partial implementation of OBD-II which General Motors used on some vehicles in 1994, 1995, & 1996. (GM did not use the term OBD 1.5 in the documentation for these vehicles — they simply have an OBD and an OBD-II section in the service manual.)

For example, the 94–95 Corvettes have one post-catalyst oxygen sensor (although they have two catalytic converters), and have a subset of the OBD-II codes implemented. For a 1994 Corvette the implemented OBD-II codes are P0116-P0118, P0131-P0135, P0151-P0155, P0158, P0160-P0161, P0171-P0175, P0420, P1114-P1115, P1133, P1153 and P1158.[5]

This hybrid system was present on the GM H-body cars in 94-95, W-body cars (Buick Regal, Chevrolet Lumina ('95 only), Chevrolet Monte Carlo ('95 only), Pontiac Grand Prix, Oldsmobile Cutlass Supreme) in 94-95, L-body (Chevrolet Beretta/Corsica) in 94-95, Y-body (Chevrolet Corvette) in 94-95, on the F-body (Chevrolet Camaro and Pontiac Firebird) in 95 and on the J-Body (Chevrolet Cavalier and Pontiac Sunfire) and N-Body (Buick Skylark, Oldsmobile Achieva, Pontiac Grand Am) in 95 and 96 and also on '94-'95 Saab vehicles with the normally aspirated 2.3."

http://en.wikipedia.org/wiki/On-board_diagnostics#OBD-1.5

[robertisaar]

wikipedia..... i should edit it to reflect the actual vehicles then.

people only call the 93-95 3100 PCM "OBD1.5" due to it using flash PROMs, something that started appearing in ~1991 or so IIRC. there is nothing about it that isn't OBD1.

http://www.obdii.com/connector.html

the list at the bottom are the actual "1.5" vehicles in that they are basically OBD2 but before it was fully implimented. the only GM applications being 95 F-bodies with 3.8, some 4.3 blazer/S10 models and 2.3 J-bodies.

[SappySE107]

I should edit this thread to reflect what I believe too. Maybe ill start a site called OBD1andahalf.com. You better start editing lots of posts on this site too now if you want everyone to stop calling it 1.5. You may as well consider it a trademark rather than factual data because its quite simply going to be considered OBD1.5 whether it is or not.

[3400-95-Modified]

It got it's term from the fact that its OBDI emissions controls yet OBDII chip style programming... Non removable flash style chip... so yeah... 1.5...

[Purple pit]

What's wrong with my injectors? Some guy called 3400-95-something told me to do it.
I got to change my sig, I also have the 65mm TCE. I'd better junk that Bosch 02, going to have a butt ton of air going into this engine.

[3400-95-Modified]

I ran 99 3400 injectors on my 95 for ages they are 19lbhr and should support a stock 3400.... But now your talking about going higher... They may not deal with that too well and you may need 22's aka 00+ injectors but then you definitely need to tune.

[Purple pit]

So for a later swap of a 3400 with stage 2 intakes that would be too much for the 19's?
Damn there goes the plan. I have the whole 3400 top end on the way and I was going to use everything for cores. Ported everything for the swap(if it will ever happen).
Bloody hell, looks like I'm back to stage 1 again. That would solve my by-pass problem and the crazy lack of port matched gaskets for stock intakes.

One other thing: I tend to snap Fel Pro upper gaskets. Am I missing something when I tighten them down? I do a crossing pattern.

[robertisaar]

I should edit this thread to reflect what I believe too. Maybe ill start a site called OBD1andahalf.com. You better start editing lots of posts on this site too now if you want everyone to stop calling it 1.5. You may as well consider it a trademark rather than factual data because its quite simply going to be considered OBD1.5 whether it is or not.

the past is the past and can't be noticablely changed, which is why now that i have proof that it's nothing more than an advanced OBD1 PCM, i'm attempting to correct the information that gets passed on as it happens.

It got it's term from the fact that its OBDI emissions controls yet OBDII chip style programming... Non removable flash style chip... so yeah... 1.5...

only in that single aspect does it share anything related to OBD2 though.... is that enough to call it something new? if so, then the cars that are OBD2 implimentations in 94 and 95 model years would be OBD1.75 then.... it's a whole bunch of unnecessary confusion.



gah, i'm getting way too damn off-topic.

[Purple pit]

Go for it. Protons do not have a positive charge and they have known that for almost 100 years. No one has even tried to change that. They have always thought it was better to teach the samething and not the true facts.

[Superdave]

Is that worth the battle though?

code aside, the 1.5 ECM isn't as easily tunable as the OBD1 or full OBD2 hardware wise. you can't just buy an emulator and drop it in or plug in a laptop and flash it. I'd leave that distinction out there so people don't go buy tuning hardware they can't use.


OP, don't be afraid to change out your stock ECM for something that you can tune. Hell, even piggybacking seems to work well.

Here is a perfect example:

local member has a '97 Sunfire, was a 2.2 5 speed. He swapped to a nasty 3500 (Strip cam, P&P'd top end, 36lb injectors). He kept the OBD2 ECU in there to run the gauges and whatever else, the engine is run by a '7730 ECM with a modified 2nd gen Jbody harness. I tuned his car a few years ago and he pretty much daily drives it to this day.