The 3.4 Plan

[00GTP4ME]

I've talked about this to some length in some of my other threads, but this time I want to come up with a solid plan for dropping to a 3.4" pulley. I don't want to invest in any mods and then just have to get rid of them in favor of the "correct" mods. I just want to do it right the first time. It will probably take me some time, so I want to get the planning part done first.

So here is my main goal: I want to do whatever supporting mods are necessary for a 3.4" supercharger pulley swap so that once I do make the swap, I can forget about it and move on without having to deal with any issues that could have been avoided with other adjustments. I don't want to have to be constantly compensating for the 3.4" pulley if that makes sense. I know I've joked about the "mod bug," and how you can never stop, but I really have no desire to do more to the car than that. This is our DD so if I did keep beefing it up endlessly, I would lose it a the "good gas mileage car." I'm okay with sacrificing a little MPG for the 3.4 pulley, but that's really as far as I want to go. So there is no need to suggest mods that aren't necessary for the 3.4" pulley unless they're easy and cheap.

What started this is that my P0420 light keeps coming on. The car runs just fine (well aside from the ticking/knocking sound when cold, the strange droning whine, the scratchy pulley sound, and the front-end knock ), and my gas mileage is just fine, but from what I've gathered so far, I'm betting the cat is bad (140K miles). I was going to just get an OEM cat and a U-bend delete from ZZP, but if those won't support a 3.4" pulley then I would rather just go straight to what will. Keep in mind, I'm not trying to build a super-racer and I want to keep costs down as much as possible while still investing enough to not damage my car or engine when I do finally put the smaller pulley in. Also, Utah does have emissions requirements so going catless is definitely not an option. I want a list if compensating mods that need to be done, and the order in which to do them.

The other grandprix forum has a lot more traffic but they seem to be the younger, thoughtless types who seem to think that the only thing that matters is how fast you can propel your car down a track and how good you look doing it, regardless of the engine fire you might have afterwards. In the two years I've been on this forum, I've received some wonderful help and advice with my car. You guys on here seem to have much more polished experience and practical sense which is what I need the most. So please let me know what you think (Bob, Rich, Tim, Jerad, I'm expecially interested in what you have to say, and of course anyone else is free to chime in).

So! Lay it on me and be prepared for me to bombard with further questions as usual! Thanks guys!

Here's the first question I need to answer. Will an OEM cat work with a 3.4" pulley or will a need a high-flow one?


THE PLAN:

1. New Cat? Hi flow or no?
2. U-bend delete
3. PCM?
4. Tuner?
5. Shift Kit
6. CAI

CURRENT MODS:

1. 180* T-stat
2. Autolite 605 Platinum Plugs (1 range colder)
3. 2.5" cat-back SS exhaust
4. Resonator delete
5. High-flow mufflers

[scuddigi_687@yahoo]

read my post for what I did on GTP issues, one major thing to worry about is the transmission they are the weak points for that car.

[00GTP4ME]

Yeah, I read that. Do you think your tranny prob is directly related to your mods? Like Jerad eluded to, I really wonder if the PCM could've helped that.

[tblake]

Originally Posted by 00GTP4ME

....So please let me know what you think (Bob, Tim, Jerad, I'm expecially interested in what you have to say....

Don't you mean to say....

So please let me know what you think (Bob, Rich, Jerad, I'm expecially interested in what you have to say.

[tblake]

I am happy with my set up, Although the ported LIM is probably not necessicary for a 3.4. I just added it because my LIM gaskets blew.

Your best bet is probably to start with installing a 180 stat and a colder range set of plugs whether they are autolite 605's or I have NGK iridiums tr6ix's (1 range colder). I went with NKG's over delco's because NGK's you can regap if you are carefull. Plus the iridiums should be good for a few years. You should have no issues running a colder set of plugs and a 180 stat while you wait for a smaller pulley.

Do you have any Mods right now? I stuck with the stock airbox to keep moisture and MAF issues from happening. I read an article on gutting the stock airbox, which I may give a shot.

[00GTP4ME]

Originally Posted by tblake

Don't you mean to say....

So please let me know what you think (Bob, Rich, Jerad, I'm expecially interested in what you have to say.

WHAT!?!?! That's your advice?!?!?! Can someone please ban this clown?



You're right, I fixed it. I haven't seen Rich on here for a while so I forgot . My apologies Rich . I do very much want your thoughts as well.

Originally Posted by tblake

Do you have any Mods right now?

Oops. Forgot that part too. I'll add my current mods to the first post.

[grandprixgtx00]

first things first, do you have access to a ODB II scanner, or something capable of scanning for KR? All cars respond to mods different, and KR is your worst enemy when dropping pulley sizes (as im sure you are already aware)

i good cheap scanner i would recommend is the LS1m. here is a link to check it out http://www.ls1m.com/Main%20Menu.htm

now, as Tim suggested you can do the cheaper things first, IE colder plugs, and 180 tstat. you will def want to get a PCM, or have someone tune yours. Ubend delete is a good idea, and a great way to reduce KR.

you will also want to get a CAI (not a WAI like you had on there before ) one that goes into the fender is the best IMO

things like headers and DP are recommended for more "kick in the pants" feeling, but not needed.

I'm sure I'm missing a few things, and will chime in again after work. just remember when modding...scan, scan, and scan more. you can never be too careful

[richtazz]

Originally Posted by 00GTP4ME

You're right, I fixed it. I haven't seen Rich on here for a while so I forgot . My apologies Rich . I do very much want your thoughts as well.

Darn it, now I have to stop the banning proceedures...!

For the 3.4 pulley, I would suggest a remapped PCM (or a tuner as both serve the same purpose. The tuner would be a better investment if you can't help yourself modding more later), and hi-flow cat with u-bend delete to go along with the mods you have already done. Also do the trans shift kit mod as described by Bnayor's thread in the tips and maintenance subforum, here's the link.

http://www.automotiveforums.com/vbul...d.php?t=899929

[00GTP4ME]

Originally Posted by grandprixgtx00

first things first, do you have access to a ODB II scanner, or something capable of scanning for KR? All cars respond to mods different, and KR is your worst enemy when dropping pulley sizes (as im sure you are already aware)

No, I don't have an OBD II scanner. The only place that I could think would have one is just the shop I usually take my car to.
All I knew was that KR = bad. That's pretty much my depth of understanding there.

Originally Posted by grandprixgtx00

i good cheap scanner i would recommend is the LS1m. here is a link to check it out http://www.ls1m.com/Main%20Menu.htm

That's cool, but it doesn't show a price, where to get one, and it says they don't make them anymore!

Originally Posted by grandprixgtx00

will def want to get a PCM, or have someone tune yours.

I have a plan for the PCM (I'll get mine tuned). Does that need to be done at a certain point or just whenever as long as it's before the pulley swap?

Originally Posted by grandprixgtx00

Ubend delete is a good idea, and a great way to reduce KR.

If I get a U-bend delete then that means I'm going to keep my stock manifold and everything. Will the stock exhaust manifold, down pipe, all of that handle a 3.4" pulley? Can I use an OEM cat with a U-bend and call it good?

Originally Posted by grandprixgtx00

you will also want to get a CAI (not a WAI like you had on there before ) one that goes into the fender is the best IMO

You're never going to let that one go are you? Give me a break, I've seen a ton of guys with that same set-up. But yes, if I do an intake mod, I'd go with a true CAI so I don't have to take Jerad's beatings anymore.

Is a CAI necessary for a 3.4" pulley?

Originally Posted by richtazz

Darn it, now I have to stop the banning proceedures...!

Originally Posted by richtazz

hi-flow cat with u-bend delete

So a hi-flow cat the only way to go?

Would this one work? http://www.zzperformance.com/grand_p...=364&catid=110 If so, I'm thinking I'd get the U-bend delete at the same time and then just have the P0420 code deleted because the hi-flow cat will most likely trip the codes, right?

Will I pass an emissions test with a hi-flow cat?

[grandprixgtx00]

Originally Posted by 00GTP4ME

That's cool, but it doesn't show a price, where to get one, and it says they don't make them anymore!

you are correct, they are not made anymore...but you can find them used for usually around $100. I was actually thinking about picking this one up. Not sure if this is legal, since its another forum, but I'll post the link anyways (I'm sure Bob will ban me if its not legal )

http://www.gpona.com/forums/gp-car-p...le-t18955.html

I have a plan for the PCM (I'll get mine tuned). Does that need to be done at a certain point or just whenever as long as it's before the pulley swap?

the PCM will need to be tuned to specs WITH the 3.4 on, along with all supporting mods you have done.

If I get a U-bend delete then that means I'm going to keep my stock manifold and everything. Will the stock exhaust manifold, down pipe, all of that handle a 3.4" pulley? Can I use an OEM cat with a U-bend and call it good?

yes, a Ubend delete will work just fine with everything stock.

You're never going to let that one go are you? Give me a break, I've seen a ton of guys with that same set-up. But yes, if I do an intake mod, I'd go with a true CAI so I don't have to take Jerad's beatings anymore.

you know I'm just messin' with ya Matt. A CAI is strongly recommended, since with a good one it will bring cool air into the motor. Cool air will obviously make the motor run a bit cooler, therefore causing less KR.

[richtazz]

the newer hi-flow cats should still work and pass emissions. With a 3.4 pulley, you need to have a good exhaust flow. A new stock cat with the u-bend should flow sufficiently, but may not causing bckpressure that may lead to KR. Plus, the aftermarket stock cats are no more apt to pass emissions testing than a high flow, so why not get the extra flow for the same money? Reprogramming the PCM to drop catalyst monitoring would keep the CEL off, but it may not pass emissions if the parameters aren't there. I guess that would depend on how stringent your state's test is.

[00GTP4ME]

Originally Posted by richtazz

the newer hi-flow cats should still work and pass emissions. With a 3.4 pulley, you need to have a good exhaust flow. A new stock cat with the u-bend should flow sufficiently, but may not causing bckpressure that may lead to KR. Plus, the aftermarket stock cats are no more apt to pass emissions testing than a high flow, so why not get the extra flow for the same money? Reprogramming the PCM to drop catalyst monitoring would keep the CEL off, but it may not pass emissions if the parameters aren't there. I guess that would depend on how stringent your state's test is.

Sweet. So if I order a high-flow cat, U-bend delete, and a shift kit from ZZP, that's all I need from them, right?

I'll be able to get a DHP tune on my PCM.

So that should be it???


Oh. And where should I get a pulley?

[grandprixgtx00]

Originally Posted by 00GTP4ME

Oh. And where should I get a pulley?

i recommend the Modular Pulley System. I've had nothing but good things to say about them, as well as from alot of other people

http://www.zzperformance.com/grand_p...=205&catid=111

of course you are going to need a puller as well

[richtazz]

I think those three mods as well as a PCM tune should just about do it. It may take a little fine tuning as far as plug heat ranges go as every car seems a little different as to what is need for KR control.

I agree with Grandprixgtx00, the modular pulley would better fit your "ok, maybe ONE more mod" mentality...LOL! And the pulley puller is another thing you'll need as well.

Good luck and keep us posted as to how it works out.

[00GTP4ME]

Sweet guys, thank you so much for the help!

Now it's the nitty-gritty:

For the U-bend do I want the one WITH rear O2? I'm thinking I do because if emissions saw I had no O2 sensor, could that come back and bite me? What are your thoughts there? Should I order the 2.5" gasket as well? I'm clueless when it comes to this stuff.

As far as the cat goes, I was just going to get this one?
http://www.zzperformance.com/grand_p...ts1.php?id=364
2.5" in/out is what I need, right?

And is this the right shift kit?

http://www.zzperformance.com/grand_p...ts1.php?id=570


Do I have the freedom to do this in any order I wish, or is there a certain order that I should go in and do certain things need to be done at the same time?