97 gtp pully change

hey all im new here and im looking to increase my cars HP without spending too much or causeing damage. iv been looking into the 3.4 and 3.2 pullys and would like to do the 3.2 but iv read a little about it and the extra mods neccessary. iv got cold air intake and magnaflow straight pipe exhaust. can someone tell me a little about the parts i would need to run a 3.2 pully size? im not sure how much they cost or where is best to get them. iv also read about needing an intercooler, my brother put his own on for his turbo'd car and said he could help me do that on my own if thats possible??

thanx for the help in advance

Welcome to AF.

I would not run the 3.25" pulley unless you have supporting mods installed. High probability you will run into excessive knock retard (KR). You'll need exhaust mods to keep KR low. Bigger downpipe, PEM or headers. Even with a 3.4" pulley I'd run an Autotap test on it or get a scan gauge like an Aeroforce Interceptor to monitor it. Also, to start a re-programmed PCM module. Do you have one installed?

Intake mods like an intercooler would help keep KR in check and provide the biggest hp gain. Definitely available for the L67 engine. Most of us get our mods from 3800performance.com, zzperformance.com or pfyc.com.

http://cgi.ebay.com/ebaymotors/GM-3800-Supercharger-MPS-Pulley-L67-Grand-Prix-GTP_W0QQcmdZViewItemQQcategoryZ33741QQihZ008QQitem Z180089100687

take a look at this sale. he is offering a 3.325 size and claims it dosnt reguir an intercooler. i dont plan on spending a lot of money so im avoiding the intercooler deal yet sticking with the smalled possible size. do you think this size would cause some problems? i will probly just get a 3.4. i have not yet ordered a PCM, im trying to find a used one so its cheaper and i can keep my old one. i read on one of the sites u listed that a 97 gtp shouldnt need a check up after instalation of a diff pcm unless the engine light goes on.

thank you for your help and bearing with me in trying to learn

I'm not familiar with the brand/company but it looks good to include price. The modular pulley system is the best to use over a standard pullley system.

You really don't need an intercooler to run that size pulley. Below 3.0", yes. The problem is you will need to monitor for any knock retard (KR). Even with the colder spark plugs and CAI you may get unacceptable levels running anything pulley smaller than 3.4". I would not run any pulley less than 3.5" without a re-programmed PCM module.

As far as checkup, when you replace the PCM module a crank variation learn is normally recommended but not required. The PCM will tell you by giving a SES/CEL light and possibly a crankshaft position sensor error code. The best test is to install it and see if the car even starts, runs and no errors are triggered.

About 8 months ago I had to change my nosecone on the super charger and it came with a 3.5 inch pulley. I read this blog and just had a quick question and hope Im not being rude by asking a question on someone elses blog. I was told that the 3.5 would be fine to run without making any changes. I have noticed that I have an idle problem at times that ranges from 800rpm to 1000rpm. I also notice as Im going down the road and I let off of the gas pedal my rpms will dip below 1000rpm's and then shoot back up to 1800rpm's or so. Could this be because of the pulley by chance? Thanks

About 8 months ago I had to change my nosecone on the super charger and it came with a 3.5 inch pulley. I read this blog and just had a quick question and hope Im not being rude by asking a question on someone elses blog. I was told that the 3.5 would be fine to run without making any changes. I have noticed that I have an idle problem at times that ranges from 800rpm to 1000rpm. I also notice as Im going down the road and I let off of the gas pedal my rpms will dip below 1000rpm's and then shoot back up to 1800rpm's or so. Could this be because of the pulley by chance? Thanks

Possible but chances are there may be another cause. The supercharger is really not used in high engine vacuum-idle conditions. What is your current mileage?

An erratic idle can be caused by a dirty/malfunctioning idle air control (IAC) valve or throttle body. Also, MAF sensor and TPS.

To troubleshoot possible supercharger problems all you have to do is remove the SC drive belt and then test it to see if the problem went away or is still there. You can run normally without the belt hooked up.

alright that makes sense. thank you for the help. so if i get what your saying then i should get a PCM instaled and checked before getting this pully size?

alright that makes sense. thank you for the help. so if i get what your saying then i should get a PCM instaled and checked before getting this pully size?

That is correct. :thumbsup:

Better safe than sorry. KR is bad stuff and the improved programming of the aftermarket PCM modules adjusts for it and allow a smaller SC pulley. Good luck.

alright so i have ordered everything but the colder plugs you speak of. i went down to good ol auto zone and they didnt have anything and the guy behind the desk told me colder plugs would be condradictory for what im doing and i want hotter plugs. !!?? i walked out thinking he didnt know what he was talking about. so now, what plugs should i use? specific # of them maybe? i have found some is this what i want?
NGK Iridium plug 5599 ITR4A-15 0.060 SUPERCHARGED

Most of us with modded GTPs use Autolite Copper Core spark plugs. Reason is reasonable cost, availability and the easy numbering system as to the heat ranges. You can get them at Walmart. The link below will describe it better.

Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=652642)

However, they do not last as long as the Platinums and Iridiums. Autolite APP605(double)/AP605(single) Platinums will work fine for a 3.4" SC pulley and last a long time. As will NGK spark plugs but I do not have the heat ranges off the top of my head.

As far as the advice from the Autozone parts guy on going to a hotter spark plug. :screwy: :lol:

ok so i got some serious problems here now. i got the pcm, traded out the little chip under the plate on the side. put it in now problem. but iv taken my car to 2 places and both say they cant get my stock pully off. one of the places was even a GM dealer which i figured would be able to do it if anyone could. they said they got the belt lose and the pully clamp thingy on the pully but it just wouldnt budge. the only other method they suggested was taking off the supercharger and completly desembling it and then they still wernt sure if it would come off. and a bill would be reaching $400. any ideas?

What type of pulley puller are they using? It takes the special SC pulley puller like from ZZP or companies like Pulley Boys. They are made specifically to remove the pulley on an Eaton M90 blower. Not just any common pulley puller will work. I have the one from Pulley Boys.

Click here for ZZP (http://www.zzperformance.com/grand_prix/products1.php?id=199&catid=111)

Click here for Pulley Boys (http://www.pulleyboys.com/gms2pt.html)

this site seems to not be working now:

http://alpineecho.com/catalog5/default.php/cPath/2

but that is where i got my puller, and it worked like a charm...

i have no clue what they were using. im guessing they SHOULD have the right parts. i mean they sell other GTP's so it seems like they would have had a pully remover for the job. but thanx guys this gives me hope that i can still put on this new pully. maybe its worth it to buy a pully remover myself and do this?

I wouldn't make any assumption when it comes to the dealers. You would think they knew what they were doing but it is normally not the case. Dealers don't even carry parts for the blower with the exception of the supercharger oil. :eek:

I would get the right SC pulley puller. It will pay off in the long run especially if you have plans on replacing the pulley later. Definitely a DIY job. Good luck.

do i need to get the plate backing when i rent the tool? its an extra $35

alright i already ordered the pully remover with the backing. i hope this works but im worried il have the same problem as the dealers working on my car did. i also ordered a 180 deg tstat with drilled holes. it seems easy to install too. after i get the new pully on how do i know i have the belt re-tightened enough?

The 180 degree thermostat is a good move to help reduce knock retard.

The stock SC belt should work fine and the tensioner will do the adjustment automatically for you. However, I would inspect the belt you have closely. It you have alot of mileage on it or any cracking then I would replace it. Most of us use the GoodYear Gatorback to insure no slippage/noise and loss of boost especially at high rpms.

wow that was easy to change lol. idk they were thinking when they said they couldnt get it off. i doubt they even tried, o well i didnt get charged for it. iv driven it a lil hard and still no trace of KR. i can tell a big diff in the temp of my car from the drilled 180 tstat. the pully also gives an awsome quick response to very little gas. when i was doing the changes to my car my brother was looking at the psi gate or something. he mentioned something about doing some mods to possibly up the psi. psi mods scare me cause he nearly blew his car with a turbo. is there any simple mods for psi tho?

You can try the boost bypass valve mod. You may or may not notice any change or benefit. See link below.

Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=679482)

Actual boost is governed by the supercharger pulley size and the capacity of the blower itself. We do not have a waste gate like on turbos. Adjusting the boost valve will change the time boost comes in or out and does not vary the total amount of boost.

so its been a few months since i did the pully swap. things are perfect and i like the changes. but i have a real problem that is rather very irritating! i ordered the pully tool from ZZPerformance as a rental for 35$. i was to be returned a check for the remainder or core deposite of 75$. i returned the tool in time and with shiping insurance and signed release via USPS. after 3 weeks of my shiping the tool i emailed ZZP wondering about the refund. long story short-the guy is claiming he never got the tool and will not return the money i am owed. i still have every reciept from every transaction and emails of his false statment. i do not just want to claim it off with usps cause i wont get what i am owed still

i will never do business with them again and i wouldnt suggest anyone else rent a tool from them. has this happened to anyone else?

I've done business with ZZP but never rented the pulley puller and purchased one outright. I don't know of anyone else that had problems with rental.

If you have proof of delivery back to ZZP via UPS then I don't see why they are giving you such a hassle and headache. Who is the guy that claimed he never received the tool and what is the name of the person that signed for it.

its usps, wish it was UPS. unfortunatly they dont keep record of anything like i thought they did. they gave me a tracking number but apparently it dosnt work :( so im left with nothing but a reciept from paying for shiping.

eric devries is the guy who responded to all my emails even though the guy who sent me the thing was Uzoma Iwuagwu. thats who i returned it too

Ah USPS. So I am assuming you did not request Delivery Confirmation and/or Signature Confirmation.

Same thing happened to me with the pulley puller. It's been over a year, and I haven't seen any money.

Same thing happened to me with the pulley puller. It's been over a year, and I haven't seen any money.

ya im almost possitive this guy is jipping us on purpose cause he knows theres nothing that can be done about it. im gona drive to the address it was shiped from and see how he feels then.

ya im almost possitive this guy is jipping us on purpose cause he knows theres nothing that can be done about it. im gona drive to the address it was shiped from and see how he feels then.

I've been following your post as I'm interested in some of this for my SSEi which I'll get to later. But just a heads up on shipping ANYTHING with USPS. Don't do it. I ordered a new item back in May this year with shipping insurance. It started with a tracking number that didn't work, then one that did with a dead end trail. So far the item has never been seen, no insurance coverage, the seller is still trying to get his end covered and USPS has no info on it. The same story I kept getting when trying to track it. I ended up being covered by Paypal and to this day I've never been able to get anything from USPS and the seller is also still fighting this. It may not be ZZ that's the problem here. Sorry but just my personal experience that sounds all to familiar here.
I'm looking for a little advise on a problem I'm having with very low boost, about 2lbs max. Everything seems to be working properly, the boost solenoid seems to be working ok but under load only about 2lbs boost. I've tried the bypass mod that ZZ Performance has posted but no difference. I'm guessing my bypass valve is leaking by. Please if anyone has some input on this let me know. i don't know if the altitude would effect it this much but I am at about 3400 ft. I don't want to try any pulley mod's until I get this straightened out.