Cadillac CTS-V - supercharger help

I know there is only a few of you guys out there, but I have a couple things I wana do after I get these lifters replaced.

The last things I really wana do to my car are meth and a smaller pulley for the supercharger (MP112)

My tuner says he doesnt really tune for meth(not that he doesnt know how)BUT, He's gonna leave the tune how it already is, but tune the meth in a different "table" I guess. So if my system goes down, it will run how it did without the meth

My question is. What size pulley should I get for my supercharger?

And also, what is the factor for how much RWHP you will gain with each pound of boost?

Generally 20hp/lb boost. I would consider the 10% overdriven harmonic balancer kit. It will give you more boost than going to a 2.6 pulley which you have to have custom fabbed (that's how I got mine was $140). This way you can switch to an 8 rib setup at the same time as over driving the supercharger so you can help prevent belt slip.

Also consider that is not a linear boost to horsepower ratio as efficiency is another factor.

I know there is only a few of you guys out there, but I have a couple things I wana do after I get these lifters replaced.

The last things I really wana do to my car are meth and a smaller pulley for the supercharger (MP112)

My tuner says he doesnt really tune for meth(not that he doesnt know how)BUT, He's gonna leave the tune how it already is, but tune the meth in a different "table" I guess. So if my system goes down, it will run how it did without the meth

My question is. What size pulley should I get for my supercharger?

And also, what is the factor for how much RWHP you will gain with each pound of boost?

He is tuning using the IAT sensor. If the temps rise (meth failure) then the tune will start pulling timing out. He can also have it dump fuel if the temps rise (meth failure).

You MUST have the fast acting IAT for this to work, the Omega thermosister. Have one?

Pulley size with the 112 seems to be a 2.6 and that is as low as anyone goes. What PSI are you at now?

The factors I came up with when researching a LOT about pulleys were these.

.2 drop in pulley size nets roughly 1.5 lbs. boost. This isn't a hard rule though and I'm sure some would disagree. Look for some great information HERE (http://www.ls1gto.com/forums/showthread.php?t=424889) on guessing your boost/power levels.

And for every 1lb boost you should gain roughly 20HP. Again this is a really rough guess because the timing you put into the motor has a large part in it all.

Hope that helps and I hope you got rid of that CEL!


Onefast you beat me! Good info about the 8" crank pulley but it is a large expense and requires a lot more work too. Personally if you have the blower off you are better off going 1:1 rears. Then you can run a 3.1" front pulley with stock crank and not worry about slip. A PITA though if you don't have the blower off.

Meth basically cools the incoming charge air and raises the octane, both of which allow you to run additional timing advance. the tune should not be too hard, just add some advance into you "High Octane" timing tables. You still have the "Low Octane" tables also if you encounter a lot of detonation, but i would not count on this table as your fail safe.


It depends on what type of pulley you already have, I bought a 2.6" but was unable to use it b/c I have the newer style "modular" style pulley and they cannot be interchanged with the older ones that are available, so the 2.8" that came with it is the smallest that you can go. I tried to post pics but they wouldn't attach. I can email you if you like.

It may actually be easier to go with an OD crank pulley instead of a smaller S/C pulley so you don't have to worry about belt slip.

Dmm you can in fact by the "modular" Tvs style pulley as a 2.6

what comes on the stock supercharger.... 2.8?

woops, just saw that

so the 2.6 slips?

Dmm you can in fact by the "modular" Tvs style pulley as a 2.6

Huh...well damn. I was told that the 2.8" was the smallest offered when I called.

And yes, 2.8" is what comes on the 112.

The stock is 2.8 and no that 2.6 won't necessarily slip but it is possible. Twitch runs one and says he doesn't have slip but its dependent on the belt you run also.

how much boost will a 2.6 give you?

how much boost will a 2.6 give you?

1.5 lbs. more than stock! :)

Dmm you have to have one custom manufactured because Magnuson does not offer them. There is an ebay store that sells all the Tvs style pulleys. I asked them to make me 2.6 and they did. If you want me to look up the company specifics let me know.

so im guessing the stock 2.8 gives 7LBS so the 2.6 will give you about 8.5

I know the thing is maxxed out and it's super small, but I wana use the meth to counteract all the heat that is going to be produced

I am planning on going the same route. I have the meth kit and 2.6 pulley. I just need to install the meth kit and save some cash for a tune.

can I get the info on where you got the 2.6?

South Florida pulley headquarters.
Terry reals is the owner. Email: wyd_trkr@bellsouth.net

if I ask him for a 2.6 for the MP112 he'll now what to give me?

Or do I have to explain it a little?

http://item.mobileweb.ebay.com/viewitem?itemId=400136248898&index=4&nav=SEARCH&nid=71117603072

Same seller as this listing. Explain you have a mp112 for a ctsv and it uses a Tvs style hub and you would like a 2.6 in one.

when i did the 2.6 on my car it wasnt hard to get to fit. i just filed a minor amount off the bracket directly behind the pulley and never had a problem with it. it wasnt much what so ever and only took about 10 mins using a hand file.

i saw a 1.7 psi gain with a cam and long tubes. ran a total of 9.6 psi and gained 42hp/33tq ish. that might be off a number or two bc i dont have the sheet anymore and dont remember exact numbers. to put down a total of 530/510.

damn i kinda miss my blower. cant beat that whine.

^ arent you going for bigger and better things?

What were the specs on ur cam again?

With the Tvs style it will require no grinding

http://item.mobileweb.ebay.com/viewitem?itemId=400136248898&index=4&nav=SEARCH&nid=71117603072

Same seller as this listing. Explain you have a mp112 for a ctsv and it uses a Tvs style hub and you would like a 2.6 in one.

That is awfully expensive compared to where I got mine. http://www.smoothflowpulleys.com/GTO_Index.html

That said I haven't gotten it yet and I ordered on the 26th. Of course It looks like a small outfit so I'm not to worried.

Wow I wish I knew about them when I bought mine!

Wow I wish I knew about them when I bought mine!

Yeah much cheaper if I actually get it!

That's the key

It actually showing up at your doorstep

He will have to pull fuel out when you do meth otherwise its gonna be very rich. Just an fyi. He can mess with the timign based on IATs but i dont think he can touch the fuel side based on IATs.

^ arent you going for bigger and better things?

What were the specs on ur cam again?

Ya I am. I'm just waiting for Callie's to get their shit straight and get my crank to me so I can get the new motor built and get it in the car.

The cam specs are a 234/242 .598/.621 112lsa. Pretty big and sucks now that it's just a cammed ls6. But worked great with the Maggie.

234/242 .598/.621 112lsa

Thats an odd cam for a blower car. Definetly more suited for n/a or spray.

I know there is only a few of you guys out there, but I have a couple things I wana do after I get these lifters replaced.

The last things I really wana do to my car are meth and a smaller pulley for the supercharger (MP112)

My tuner says he doesnt really tune for meth(not that he doesnt know how)BUT, He's gonna leave the tune how it already is, but tune the meth in a different "table" I guess. So if my system goes down, it will run how it did without the meth

My question is. What size pulley should I get for my supercharger?

And also, what is the factor for how much RWHP you will gain with each pound of boost?

With a 2.6 you're going to get some good slippage at above 5k rpm. If you're going to go that small I'd suggest switching to 8 rib and getting a decent tensioner like the ECS one. Really helps.

I ran a 2.7 + 8 rib OD dampner + ECS tensioner + Gates green belts on my old maggie. Didn't slip but then it wasn't exactly cheap either. At least it stopped shredding through belts.

what's this 10% overdriven harmonic balancer kit for the 112?

what's this 10% overdriven harmonic balancer kit for the 112?

Innovators West

234/242 .598/.621 112lsa

Thats an odd cam for a blower car. Definitely more suited for n/a or spray.

No, its not. This is what I have been trying to say for a while, it has only been very recently that the super high LSA cams have been "The Rule" in an attempt to seal off the cylinder and prevent the dreaded "boost leakage".

I don't have the time or the desire to get into this again, my point (as it always has been) is that a cam with overlap will make more power than a cam with negative overlap (emission's compliance notwithstanding, of course), especially on a roots blower.

He can also have it dump fuel if the temps rise (meth failure).

Just an fyi. He can mess with the timign based on IATs but i dont think he can touch the fuel side based on IATs.

I don't just say things that I think are true. ;)

PE > Add vs. IAT > PE Fuel adder vs. IAT.

http://i349.photobucket.com/albums/q365/CancerJCC/Internet%20Uploads/PEIAT.png

Some of you guys know better than I do, but this is my opinion on the matter. I don't think you can really tune in a safety measure for a meth failure on a Maggied car. On centri/turbo your meth and IAT sensor are after the compressor. The IAT temp drop with meth is HUGE compared to our setups.
At what temp do you set your failsafe on our cars? Say meth keeps you below 130* and you set your adders at 140*. If my meth goes out on a cold day, no way I'm reaching 140* even without it.
My solution is that my Aeroforce gauge is set to light up at 2* of KR. That's the best I can think of, but I'm not the smartest guy on here.

I got my old style 2.6" pulley from pulleyboys. No slip, and wintertime boost was hitting 10 psi with just highflow cats. Cam/headers would see less boost (restriction).
After a few months I started getting belt problems and decided to upgrade the tensioner. No problems since then.
Got it from David at Magnuson for a little over $100

http://i80.photobucket.com/albums/j177/Gxxr1/IMAG0352.jpg
http://i80.photobucket.com/albums/j177/Gxxr1/IMAG0351.jpg

I should note that the belt problems weren't necessarily due to the smaller pulley. Started getting belt walk and noticed my gates belt stretched out a couple inches. So I installed the belt that came with the Maggie and everything was fine,,,,,,until I shredded it by letting it rub against a clamp bolt. Then I kept having problems with new belts and figured the tensioner wasn't doing up to the task anymore.

Oh, and as for the Meth kit. I don't think you need to go crazy with the expensive controllers. With the Maggie, boost jump up so fast it's like an on/off switch anyway. I say get a quality pump, make sure your wireing/hose routing is spot on and control the amount of meth with nozzle size. I use my smaller nozzle at full psi so the fluid atomizes better. This helps your fueling and is easier on the rotors.

This all makes sense to me, but let me know what you guys think.

Tony

Some of you guys know better than I do, but this is my opinion on the matter. I don't think you can really tune in a safety measure for a meth failure on a Maggied car. On centri/turbo your meth and IAT sensor are after the compressor. The IAT temp drop with meth is HUGE compared to our setups.
At what temp do you set your failsafe on our cars? Say meth keeps you below 130* and you set your adders at 140*. If my meth goes out on a cold day, no way I'm reaching 140* even without it.
My solution is that my Aeroforce gauge is set to light up at 2* of KR. That's the best I can think of, but I'm not the smartest guy on here.

I got my old style 2.6" pulley from pulleyboys. No slip, and wintertime boost was hitting 10 psi with just highflow cats. Cam/headers would see less boost (restriction).
After a few months I started getting belt problems and decided to upgrade the tensioner. No problems since then.
Got it from David at Magnuson for a little over $100

I should note that the belt problems weren't necessarily due to the smaller pulley. Started getting belt walk and noticed my gates belt stretched out a couple inches. So I installed the belt that came with the Maggie and everything was fine,,,,,,until I shredded it by letting it rub against a clamp bolt. Then I kept having problems with new belts and figured the tensioner wasn't doing up to the task anymore.

I think you are right Tony. Without the meth dropping the IAT a LOT like on a centri car you just can't effectively tune for meth with a maggie. Although I am using the tables as an AID I am predominately relying on my AFR gauge and I watch it like a hawk when in boost. If I see 11.xx then I can assume my meth has stopped spraying and get the hell out of it. (On meth i'm around 10.8) It may or may not be to late depending on how aggressive you were with the meth. IE don't tune to be "meth dependent".

I wish we could see a much larger temperature drop because I am confident the IAT sensor is reading quickly enough to allow a benefit.

Beyond the iats cant you also use o2 sensor and knock sensor information to see if you are leaning out?

I guess i'll have to pick his brain a little when I go to get this installed.

Beyond the iats cant you also use o2 sensor and knock sensor information to see if you are leaning out?

You need a dedicated Air fuel ratio gauge. The o2 sensors are shut off and don't control fueling WOT. You can monitor for KR yes.

The thing is that if you are on the ragged edge. (Tune leaned out for meth and timing dependent on meth spraying) then neither KR or an AFR gauge are going to save you in the event of sudden stoppage while WOT.

The key is to push it just a bit so if meth were to stop spraying you can tell and back off. Push it too far and there isn't a back off point available...

I do have a dedicated wideband o2 the problem is its standalone and not monitored by the Ecu.... if only there was a way to incorporate that.....

I guess i'll have to pick his brain a little when I go to get this installed.

Here are a couple visuals for you.

http://i349.photobucket.com/albums/q365/CancerJCC/Internet%20Uploads/SparkPull.png

This is my timing being pulled dependent upon the entering air temp (IAT).

You can see that when my IAT reach 153.5° (The PCM interpolates between 149°-158°) I start to aggressively pull timing (-5°). The theory is that if my meth were to stop flowing I would see a spike in IAT and thus the PCM would pull timing.

Now I don't always see 153.5° IAT when I'm not spraying so this method is somewhat flawed. If I moved down to the 149° column I would have timing being pulled at 144.5° IAT and this is a temperature that I see. So you can see that this doesn't work perfectly.

Now the flipside for the Centri guys is that they can ADD timing with this table. (Note this isn't what I'm using its just an example)

http://i349.photobucket.com/albums/q365/CancerJCC/Internet%20Uploads/MethIATExample.png

As their meth sprays and thus cools their IAT they can add timing in. If the meth were to stop spraying then they would just not have timing ADDED in. A win win.

The reason we can't do this is because our meth spraying doesn't cool the charge enough. I personally was hoping to set the tune up this way but it just isn't going to happen.


For the second safety measure I have it set up to dump in extra fuel in the event of IAT increase (meth failure).

http://i349.photobucket.com/albums/q365/CancerJCC/Internet%20Uploads/PEIAT-1.png

At 149° (interpolated between 140°-158°) I start to add in fuel aggressively. Again of course I won't necessarily hit 149° even with no meth so this method has its flaws.

The bottom line is just like Tony said there really isn't a 100% safe way to tune meth to the edge like the Centri guys have.

Hope this helps you guys deciding to meth or not to meth.

I do have a dedicated wideband o2 the problem is its standalone and not monitored by the Ecu.... if only there was a way to incorporate that.....

The incorporation is YOU! haha

Their is another way but it gets more complicated than I am willing to work with.

You could wire up a flow sensor RIGHT next to the injector. This flow sensor would then be in turn wired to your IAT sensor. This in turn would have your timing table (in your tune) setup to pull out crazy timing at a higher temp than you will ever see. The way it would be wired up is that if flow stops then the IAT goes to a full 5v (or ground, whichever way it thinks is highest temperature) and thus pulls out all of the added timing you have for the meth.

Make sense? Who knows maybe one day...

I cant always rely on myself to watch an afr gauge while lashing the throttle :p. At some point I want to sit back and enjoy the power

I cant always rely on myself to watch an afr gauge while lashing the throttle :p. At some point I want to sit back and enjoy the power

Yeah I feel you on that. Try tuning yourself, with everything that could go wrong you drive yourself crazy worrying about your car instead of beating the piss out of it like it should be. Not that I don't romp on it often but I'm WAYYY to aware of all "what ifs".

I do have a dedicated wideband o2 the problem is its standalone and not monitored by the Ecu.... if only there was a way to incorporate that.....

You can always try this out:
http://www.aemelectronics.com/wideband-air-fuel-systems-15/wideband-failsafe-gauge-84/

They have one for meth also. Of course it gets rather expensive if you do it properly and add piggyback controllers but with just basic flashing lights it does it's job and warns you when your AFRs are leaning out.

Yeah I feel you on that. Try tuning yourself, with everything that could go wrong you drive yourself crazy worrying about your car instead of beating the piss out of it like it should be. Not that I don't romp on it often but I'm WAYYY to aware of all "what ifs".

Hehe, yeah, I'm big time regretting getting an AFR gauge that's always on. :eek2:

so im guessing the stock 2.8 gives 7LBS so the 2.6 will give you about 8.5 ...Just a side note, but I have a 2.8" drive pulley and max out at 5.8 psi at just over ~6200 RPM, so boost by itself is not necessarily the most meaningful parameter. What you want is flow in terms of mass of air per unit of time. Twitch (Tony) has pointed out that those with headers run lower boost pressures than those with OEM exhaust manifolds. That's an indicator of higher flow with the headers thus lower boost. Boost for one guy is not necessarily the same for the next guy.

Okay, back on point. I see meth as like insurance against getting spark knock due to too much timing, too hot a A/F charge, and/or too lean a mixture.

If I was you, meth is good, but I'd spend the extra coin on an 8" crank pulley. Compared to the 7-1/4" OEM crank pulley, this is about a 10% increase in S/C speed, i.e. boost, and will be less likely to slip. Doing the 2.6" drive pulley alone results in a little under 7% increase in boost. Doing both, if you've a mind to, will get about 17% more boost on paper.

Whatever you do, let us know your results.

If you are using meth and running right on the edge so that you worry about whether its working or not, you could always install a pressure switch in the line going to the nozzle to illuminate a simple indicator light rather than try to focus on an AFR gauge. Especially at night, those damn AFR things are like Las Vegas in your face in the dark...too busy for me. I have one, but it's only for tuning and I have it so that it plugs into the cigarette lighter so its easy to go from vehicle to vehicle.

ok, so I know where to get the 2.6"

Where is everyone getting their 10% crank pulley?

Innovators west

http://www.innovatorswest.com/993-8-Rib-Kit.html

HOLY CRAP ^

I guess i'll just be getting the smaller pulley and meth after all

HOLY CRAP ^

I guess i'll just be getting the smaller pulley and meth after all

if ur gonna run the 6rib 2.6 then make sure u change the idler pulley on the tensioner to a v2 idler pulley.. its a half inch bigger and has lips on it to help with belt guide. it also helped get rid of belt slip. im running a overdriven balancer with a 2.6 and that pulley helped out alot. im also running a half inch shorter belt. im at 103in but yours will be shorter due to the stock damper
that v2 pulley was like 20 bucks. do it!

everything from the V2 bolts right up?

No just the pulley that's on the tensioner. I'll take a pic when I'm home

ok thanks

You can piece together the parts with the jegs balancer and innovators west idlers, tensioner,power steering and alternator pulley for about $850.

damn, I'll have to finish all my other stuff first

Didnt know the funds were gonna have to go that high

if ur gonna run the 6rib 2.6 then make sure u change the idler pulley on the tensioner to a v2 idler pulley.. its a half inch bigger and has lips on it to help with belt guide. it also helped get rid of belt slip. im running a overdriven balancer with a 2.6 and that pulley helped out alot. im also running a half inch shorter belt. im at 103in but yours will be shorter due to the stock damper
that v2 pulley was like 20 bucks. do it!

Interesting. Thanks for the tip.

Wcryan fyi in California it is illegal to sell washer fluid with methanol in It... you have to buy pure methanol and mix it with water for your meth kit.

Drove to too many different auto stores before I found that out!

Sounds like California to me