Supporting Mods

Referring to the mods in my signature, what supporting mods should I get for best performance/best way to keep my car running longer? The 3 mods in my signature are the ONLY mods I've made performance wise (no supporting mods). And I don't want to have like a chain of mods I have to make either (just a made up example: have to get new brakes to support the new pulley, then have to get new doors so the brakes fit right, then a new hood so the doors close properly, etc.) Any help would be great. Oh and one more thing, could you give me names of the best valued things to get? Thanks.

Got about 131,000 miles on the car if it matters.

Boosting performance and increasing longevity don't normally go hand in hand. You have to eventually sacrifice one for the other. The more mods you perform, the more at risk you are of breaking things.

I know what your saying but I didn't mean it like that. I meant like having too much KR or other things like that.

KR is caused by the PCM detecting knock, then retarding timing to eliminate it. Your best "bang for the buck" mods to do next would be a reprogrammed PCM and hi-flow cat. The reprogrammed PCM will have new calibrations for trans shift points, injector on-time, and reduced KR sensitivity, etc... Just make sure with that 3.4 pulley, you don't try to run regular unleaded. The car will run like crap, and you could grenade a piston (#4 is the most common one to go) due to increased spark knock/ping from the higher boost created by the smaller pulley.

If you are really concerned with Knock Retard - KR then you should invest in a scan gauge that monitors KR like many of us with modded GTPs do. :grinyes:

What brand spark plugs and heat range are you currently using with the 3.4" pulley? Should be one or two ranges colder than stock.

.... and you could grenade a piston (#4 is the most common one to go)...

Stupid question, not that Im doubting your knowledge, but I'm just wondering why #4? Is it because its the center piston towards the firwall and maybe the hottest because of this?

Hey Bob, I can't believe I forgot to include colder plugs. I've been having issues with AF being really slow and sometimes pausing and I forgot to include that, so thanks for the correction.

Tblake, that would seem to be the case. Airflow over the engine, as well as surface area help to some degree in cooling. Since #4 is in the rear (less airflow than #3 in the front) and in the center (less outside surface area than #2 and #6) it seems to be the one that gets hotter and fails first.

Hey Bob, I can't believe I forgot to include colder plugs. I've been having issues with AF being really slow and sometimes pausing and I forgot to include that, so thanks for the correction.

Hey Rich. It wasn't a correction but additional info and just my two cents worth. With the 3.4" SC pulley he has a ticking time bomb without any supporting mods or monitoring capability. Your reply looked fine to me. Knock. knock, knock.......another one bites the dust. :lol:

I appreciate you saying that Bob, but I would consider it a correction (and a valid one, thanks again). The plugs should have been mentioned first, as omitting them from the list of supporting mods could lead to catastophic engine failure with his current mods.

...With the 3.4" SC pulley he has a ticking time bomb without any supporting mods or monitoring capability. Your reply looked fine to me. Knock. knock, knock.......another one bites the dust. :lol:

You too funny!! :lol:

I need some quick spark plug help. On pfyc I have a choice of TR55 or TR6, which ones do I want? I'm getting them to go along with the MSD 8.5mm plug wires.

With a 3.4 pulley, shouldn't the PCM be mod'd? Also what about the T-stat? A 180 will keep it cooler me thinks...

Thoughts?

I need some quick spark plug help. On pfyc I have a choice of TR55 or TR6, which ones do I want? I'm getting them to go along with the MSD 8.5mm plug wires.

The TR55 is equivalent to the stock heat range. The TR6 is one range colder. On NGK spark plugs the higher the number the colder. The lower the number hotter.


With a 3.4 pulley, shouldn't the PCM be mod'd? Also what about the T-stat? A 180 will keep it cooler me thinks...

Thoughts?

Yes. The 180 thermostat is optional but recommended once the weather warms up or depending on his climate.

The TR55 is equivalent to the stock heat range. The TR6 is one range colder. On NGK spark plugs the higher the number the colder. The lower the number hotter.




Yes. The 180 thermostat is optional but recommended once the weather warms up or depending on his climate.

Aah thanks good thing I wanted for a response. I was about to get the 55s cuz it sounded like that would be a lower range but good thing I wanted :) Thanks.

Also, keep in mind these NGKs based on the number are the V Power and not Iridiums. The TR6 are in reality 1 1/2 times colder than the stock but that is fine.

As an alternative the Autolite Copper Core 605 are one range colder too but cheaper. Many of us with mods use the Autolites. :grinyes: 104 is two ranges colder.

You want a mod that will help longevity? Two for you a way to scan Aeroforce makes a guage you can scan with looks nice and with that 3.4 pulley I'd definately drop in a 3" down pipe and high flow cat. That alone will take care a bunch of KR issues. PCM doesn't need changed it'll make it's own A/F changes but a reprogrammed one will take better advantage of the mods. But even off the shelf tunes aren't the best only a custom tune to a specific vehicle will net the highest gains. But definately with the 3.4 I highly recommend the Down pipe.

The best exhaust mod to take care of any KR on a L67 GTP is headers......period and at minimum PEMs with the dp. I've seen KR with the 3" dps and hi-flo CATs only up to 4 degrees and higher with burst (WOT) KR up to 8 degrees running just a 3.4" SC pulley. Man that was a long time ago. With a Stage 1 DHP, Intense or ZZP re-programmed PC module the KR drops significantly but proper exhaust and intake mods are the key to real engine longevity and overall power. The bigger downpipes are fine but you'll still have a bottle neck and potential KR unless the overall plumbing is modded to 2.5" or better throughout. Until it is scanned with the Aeroforce scan gauge or a program like Autotap on a laptop he'll never really know for sure. Also, there is part throttle, WOT and shift KR to consider therefore even a Stage 1 PCM module is highly recommended even with just a 3.4" SC pulley.