PCM Question....

I have a 3" custom FWI done right now. Whats next? Should I get a PCM first or free up the exhaust a little bit? As far as the PCM goes, how about Intense, since they are local and I can get it right now.

Now as fae as the exhaust. If I should free it up before I get the PCM, should I get a d/p with high flow cat and u-bend delete or should I just go get the u-bend delete and maybe resonator delete. I believe I could swing getting the PCM and hitting a local exhuast place to get the u-bend/ resonator delete right now. Or just ordering the d/p...

Any thoughts,

CMD

get the exhaust mods first (hi-flow cat and u-bend delete), as they are a requirement for optimum recalibrated PCM performance.

In my opinion, I think you should check out other options for the aftermarket pcm dealer you mentioned.

I took a little drive the other day and picked up me an Intense PCM flash for the GTP. I have the FWI and the 104's and 180-stat. Thinking about getting the ZZP 2.5" D/P with cat. Its bolt on. Any problems I need to know about or would this be ok.. Also after the d/p install whats next before doing a 3.4 swap safely as to not screw up my car....

Hey... I would go with the exhuast and U bend delete...then mybe headers from zzp...then the DHP pcm V1.0. I have a 2004 gtp compG with custom intake. 3.5inch Thraser Supercharger pully. Autolite 103- 3 range temp. U-bend deleted. Deleted resinator-3inch straight pipe.SLP 180 Cold Stat. Digatal Horsepower flashed PCM V1.0 I am running 1/4 in 13.9@102mph with stock tires and 93fuel.

My Intense PCM is the same as the Dhp 1.0 I thought. I went to them because they are local...I wasnt sure that I needed to actually upgrade the exhaust itself. I knew about getting rid of the u-bend for sure, the resonator maybe. From what I understand its really only good for wieght reduction purposes. You get nothing performance wise and thstock exhaust is good for at least a 3.4/w suporting mods...

In any case, those are some nice numbers at the track. What were your 60'...

Anyone else?

I think what i would have done is a cat/u-bend/res delete, and got all of it out of there. Sent in the PCM to ZZP and had them flash it with there 1.0 file. While they were at it had them put a 02 delete in with the file. the woul would have been covered all the way around. I know that is what i did with my car. sounds great. And the PCM is a great tune. DHP's are great but they can not be tuned by a normal tuner. If I am not mistaking they are locked.
Dan

an o2 sensor delete? You mean the post cat o2 sensor, right? this then allows you to remove the cat converter without a CEL coming on? How about emissions tests? When all this stuff is done to a gtp will it still pass state emmission tests?

How about emissions tests? When all this stuff is done to a gtp will it still pass state emmission tests?

GREAT Questions! I understand many states don't bother to sniff the tailpipe. The "technician" hooks the smog 'puter to the car's PCM interface. I wonder if the state's smog software is programmed to detect hacked changes in the PCM.

I hope you get answers to 'em!

My GTP is in the smog shop as I write this gobbly-gook. (Its been dropped off on the way to arbeit." I know here in California, your ride gets the sniffer up its wa-zooo, er -- tailpipe.

I see three grand prixes in the picture. Yours is getting the sniffer right now? You mean the "project car"? Did you get her running?

I think what i would have done is a cat/u-bend/res delete, and got all of it out of there. Sent in the PCM to ZZP and had them flash it with there 1.0 file. While they were at it had them put a 02 delete in with the file. the woul would have been covered all the way around. I know that is what i did with my car. sounds great. And the PCM is a great tune. DHP's are great but they can not be tuned by a normal tuner. If I am not mistaking they are locked.
Dan
DHP's v1.0 is locked, however their v1.5 is not.
ZZP's PCM is unlocked.

an o2 sensor delete? You mean the post cat o2 sensor, right? this then allows you to remove the cat converter without a CEL coming on? How about emissions tests? When all this stuff is done to a gtp will it still pass state emmission tests?

The PCM mod to inhibit any DTCs like P0420 from setting from the rear 02 sensor will not affect odb-ii run state emissions tests. You will still get an emissions readiness (IM) flag as go or pass. For example in Texas for '96 and up cars it is odb-ii port only and an evaporative emissions test. No more tailpipe sniffer. I pass mine with no problems with an Intense custom programmed PCM and that includes all of my mods to date. Intense does not lock their PCMs either.

If you decide to custom program on your own the DHP v1.0 lock is no problem with a DHP Powertuner as you can edit the bin file.

I see three grand prixes in the picture. Yours is getting the sniffer right now? You mean the "project car"? Did you get her running?

I have the 98 GTP running. :ylsuper:
It failed smog for two reasons.
First no-go was due to an after market relay that's installed in the boost solenoid circuit.
Second prang from the state of Arnold was there were not enough drive cycles for the PCM to complete its diagnostics.
I spoke to the smog tech. He said that when he saw the roll cage, gauge pod, Simpson 5-point belts, and fire extinguisher; the car was gonna get a hard look at it before it was passed on the visual. I told him it was cool. I understood the car had to be bone stock. The guy told me he even measured my pulley on the M90. (It was a stock 3.8) LOL
Back to the shop Monday for another pre-test. I'm taking it on a quite few short trips i.e. errands to complete the weekend honey-do list that will take care of the drive cycle issue.
BTW... My question was answered by the smog tech. Indirectly. The test didn't pick up my mod'd PCM.

the guy even measured your pulley? I cant believe it. If he found a smaller one on it, what would he have done? made you swap it back?

My Intense PCM is the same as the Dhp 1.0 I thought. I went to them because they are local...I wasnt sure that I needed to actually upgrade the exhaust itself. I knew about getting rid of the u-bend for sure, the resonator maybe. From what I understand its really only good for wieght reduction purposes. You get nothing performance wise and thstock exhaust is good for at least a 3.4/w suporting mods...

Anyone else?

i would have done the exhaust mods before the pcm, but oh well. Deleting the resonator is mainly for sound. If you're looking to drop pulley sizes i would recommend maybe headers OR get at least a 3.0" Downpipe not a 2.5" and definitely get rid of your ubend ASAP. Happy Modding!

**edited for confusion**

Headers is a great suggestion if you can afford them. However, with headers you do not need to waste any money on a downpipe. :grinno: People with them know what I am talking about. :wink:

Also, it is very important to check for any knock retard (KR) with any supercharger mods like a smaller pulley. Exhaust mods especially PEMS and headers help reduce KR but may not get rid of it totally. Better safe than sorry later. :eek: