Stage 2 pully from Z-spec

[john_V63400]

Im going to buy the Stage 2 Supercharger upgrade for my 01 S/C 3400
Grand Am from Z-spec. Im curious on what you other (Z-spec)RSM S/C owners think about it, and if anyone has tried it out. Im just going to buy the smaller pully from them, I baught the 36# injector from Milzys, and going to be tuning with DHp. An yes I still havent put the MAF bak in the mix.

Im curious on what boost Im going to be pumping with that pully does anyone know.

[john_V63400]

Well Just some info I found out is.....

The stage 2 pully is 150.00 USD
Bolts directly on to the RSM or Z-spec stage 1 Supercharger kit
Produces 12-15 Psi
Requies tuning, forged pistons, They recomend 28# to 30# injectors( Id go with 36# if you have all the supporting mods)
And they still told me to leave the MAF out

why is it all you guys want to put the MAF back in, but the professional enginers that made the kit in the first place recommend to leave it out, no offense, but Im confused?????

[SappySE107]

ROFL!

Seriously, did you say RSM are professional engineers? They want you to run boost on a 1 bar map setup that can't read boost. Ask anyone that works on boosted vehicles what they think about that. Sorry, but RSM changed their name to z-spec because they are a shitty company, not because they are professional engineers and had a good reputation with the RSM name.

[john_V63400]

Ok, I think I get it, so deleting the MAF sensor throws the computer into 1 bar map mode, wich cant read High boost levels. Does that still go for my 01 GA GT 3.4

[sharkey]

no, you have a 1 bar map sensor, it reads -14.7psi (vacume) to 0 psi. to read any boost, you need a 2 bar map sensor (they read from -14.7 to +14.7psi). the mf doesnt change anything with the map sensor.

[john_V63400]

So it is easier to add a 2 bar map sensor to my set up, and if I did why would that add any HP. I mean the air from the S/C goes into the engine, and the injectors are programmed to add the right amount of fuel, the spark and everything else is right, why would the computer really need to know how much psi is going in anyways, wouldnt that just be extra information the PCM doesnt really need.

[SappySE107]

you are assuming way too much from your ECM. Its not giving the right fuel and spark because it has no clue how much air is going in your motor. Adding a 2 bar wont do any good cause the ECM doesn't know what a 2 bar MAP is. You should put the MAF back in line so it can read the airflow coming into the engine. Then you need to tune it. Why it hasn't blown up yet, i dont know.

[onefastV6]

Not only does the MAF make the tuning more accurate and stable, it helps control the tranny.

Once the MAF is unplugged and you are running in SD mode, and I believe the tranny shifts at full line pressure. This over time with the added power and your tranny is going to be shot, as the 4T45e isn't know to be the strongest tranny out there.

[Azrael]

The main reason they changed their name to Z-spec: You can't sue a company that technically doesn't exist anymore. They were caught red-handed when it was discovered their "tuned" ECUs were essentially stock.

In your case with the MAP sensor, your ECU has no idea that your engine's seeing any amount of boost at all. It can only assume the engine's getting 0 PSI. You'll be doing the right thing going with the DHP setup as you'll regain the MAF and it can be tuned for a 2-bar MAP.

[AaronGTR]

Pretty much accurate. RSM/z-spec suck. They don't know how to tune... get a DHP tuner and put the maf back in already! The maf is more important to fuel enrichment than the map is on these cars, and you CAN change the setup so that a maf will work properly with it. If you get a smaller pulley, get some bigger injectors too. As long as you have the maf to tune with it will run just fine, even with the 1bar map. Most of us that are boosted are still using the 1bar, so it remains to be seen if there's really any significant gains to switching to 2bar. The tuner will allow you to use a 2bar map, but it's a new feature and still has some bugs and doesn't work properly on cars that are NA from the factory, so leave the 1bar in for now.

[sprucegagt]

why is it all you guys want to put the MAF back in, but the professional enginers that made the kit in the first place recommend to leave it out, no offense, but Im confused?????

HAHAHAHAHAHAHA!!!! Professional engineers, HAHAHAHAHAHAHAHA!!!!!

Damn that was a good laugh, I should of read this thread sooner. Get a Powrtuner and put the MAF back in before the transmission and engine decide to be boat anchors. Your current PCM is nearly stock, which means it hates boost right now, since it was never programmed for it. It will run but not at it's best, more like just getting by and it won't be long before it stops doing that.

[Azrael]

I'll amend my last post with some more info I know of RSM's SC kit. While the ECU may not be providing the required fuel the kit does include an RRFPR. While not ideal it is still giving more fuel under boost situations.

[onefastV6]

Let me add some insite here.

The main problem with the RSM supercharger is bearing failure, caused by RSM using a rubber shielded bearing. There is a replacement bearing that should last alot longer because it is a metal shielded bearing, which is better resistant to heat.

The RSM supercharger I have also had a worn key, where the pulley shaft meets the supercharger shaft. Upon inspection, this was because RSM used weak metal for the key. I purchased replacements and they fit much better and are much stronger.

As for the Tuning, I agree they should have never lied about that by any means, however with DHP and HPT this really isn't a issue.

They also removed the MAF sensor, again not a problem as you can reinstall it.

Over all between the bearing and the new key I have less than $20 in fixing what I consider to be a few oversights by RSM. These fixes should make for a longer lasting more reliable supercharger.

[AaronGTR]

That's one thing I agree on. The kit can definitely make good HP if you get the parts you need to make it work right and tune it properly. The same could be said about the magnacharger kit since it only came with a RRFPR and no computer tuning. Only real difference is the magna kit was upfront about using a stock computer, they provided for retaining the stock MAF, and it hasn't had as many reliability issues. A properly done rsm kit should make more power though since the blower is better sized and more efficient in the high end. It definitaly has potential... just bad execution on rsm's part. I think we can all agree on that.

[zofo61]

Phil is correct on all accounts.
Replace the bearing as soon as possible.It WILL fail..trust me, mine did....in North Georgia...on a Sunday...not good.I carry a stock belt in the trunck now ALWAYS!
Buy the DHP PT
Put the MAF back in
Then you can play in baby steps and enjoy the power without worrying about the big BOOM.
If you are going to go to the 2.5 pulley....do all the above but first up the injectors to at least 28#ers from a TrailBlazer, or get the 36#ers from a GTP.
As far as the RRFPR...they never put mine in...I guess the fuckers forgot that as well, and at the time I was too stupid to know it should have been in. If you need one I have an extra Vortech FMU at 10:1 that needs a rebuild($40.00) from Vortech that I will sell U for shipping costs only.
The RSM Kit is a good one only after you do the things these guys are telling you to do. Everyone agrees that they are a shit company but also I think everyone agrees that the kit has really good potential if you take your time and listen to people who just want to help and not fuck you out of your money.