Need Maggie help pls.
Thread Starter
6th Gear
Joined: Apr 2005
Posts: 6
Likes: 0
From: Moss,Norway
Need Maggie help pls.
Just mounted a maggi on my 98 conv.I can see in here that some of you have changed the pulley size.What is the hp gain you can really get if you change it.Will it more easely damage my engine?I also have a squezing belt noise sometimes...and is it really not possible to get coil covers for 97/98 with a maggie installed? 
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
If you have an intercooled Maggie you can switch to a 3.1 pulley and make 8.5psi of boost and be pretty safe with a good custom tune. Also a good blower cam will make 40rwhp difference on top of that.. 
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
The power levels in my sig were with the 3.1 pulley. I was only making 6.5psi of boost because of the cam and big 1 7/8" headers. I now run a 2.9 pulley and see 8.5psi of boost. I went from 121mph traps to 125mph in the 1/4 mile. 
Thread Starter
6th Gear
Joined: Apr 2005
Posts: 6
Likes: 0
From: Moss,Norway
Ok ...so I can change to 3.1 pulley with no other changes?....what will it gain then? Nobody here who knows where to buy Fuel rail/coil Covers for the 98 mod ...Know you can get them for the 99 and up mod but everybody says they dont have them for the 97-98
Thanks in advance
Rolf (Norway)
Thanks in advance
Rolf (Norway)
Burning Brakes
Joined: Aug 2003
Posts: 1,070
Likes: 9
From: MARRIOTTSVILLE MD
Originally Posted by chriswtx
The power levels in my sig were with the 3.1 pulley. I was only making 6.5psi of boost because of the cam and big 1 7/8" headers. I now run a 2.9 pulley and see 8.5psi of boost. I went from 121mph traps to 125mph in the 1/4 mile.
How much advance do you run at WOT on 8.5 lbs of boost ?
Thanks >>>> INTHERED
Racer
Joined: Jul 2004
Posts: 260
Likes: 0
From: Corona CA
I have a I/C Maggie with the stock pulley.(04 6spd Coupe)
For every pound of boost you should pickup around 15HP and 20TQ
I personally would not run over 7.5lbs of boost and feel safe taking the car out of town on long trips.
8.5 in my opinion is pushing it if the weather is too hot or you get a bad tank of gas.(I would feel safer runing meth/alchol at those boost levels)
Here is what you can excpect with a custom tune/Cat-back and stock pulley.(My car trapped 120MPH before the tune in bad weather so I am hoping for 123+ traps now)
For every pound of boost you should pickup around 15HP and 20TQ
I personally would not run over 7.5lbs of boost and feel safe taking the car out of town on long trips.
8.5 in my opinion is pushing it if the weather is too hot or you get a bad tank of gas.(I would feel safer runing meth/alchol at those boost levels)
Here is what you can excpect with a custom tune/Cat-back and stock pulley.(My car trapped 120MPH before the tune in bad weather so I am hoping for 123+ traps now)
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Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
INTHERED
Stock LS1 compression, 20 degs of advance at WOT, I use HP tuners to tune and log with no knock even in 100deg temps...I'm running at 11.7/1 AFR data logged with my LM1 wideband..
rolfivar
You will need to get the car retuned with any change you make...
What compression ratio do you have ?
How much advance do you run at WOT on 8.5 lbs of boost ?
rolfivar
Ok ...so I can change to 3.1 pulley with no other changes?.
Melting Slicks
Joined: Sep 2002
Posts: 2,787
Likes: 139
From: Las Vegas NV
My bud has a 03 coupe with a Maggie with a 2.81 pully installed by A&A along with a good tune by Charile. He is getting 11 PSI of boost with 468 RWHP and 498RWT out of a stock LS1 just shorty JBA headers and 390 gears. Not too bad.
Drifting
Joined: Oct 2003
Posts: 1,923
Likes: 5
From: San Antonio TX
Originally Posted by rolfivar
Is it really not possible to buy Coil covers for 98/Maggi installed? 
IMO if you do a little work on the intake, heads, cam, intercooler, you can get away with a 2.9 pully even with 90 - 110 deg air temps, you just have to tune it correctly, ie don't go to the guy that says yea I can get you 40 more hp out of this, go to the guy who says ok we are at X hp with no knock now I am going to back off of the advance and add a little fuel so that it will be safe. you can make over 500rwhp/tq with the maggie and still be safe without AI (ask me how I know).
More Than Zero
PS: chris I wondering how long it will be before you add NO2 to your setup and hit 650?
Burning Brakes
Joined: Aug 2003
Posts: 1,070
Likes: 9
From: MARRIOTTSVILLE MD
Originally Posted by chriswtx
INTHERED
Stock LS1 compression, 20 degs of advance at WOT, I use HP tuners to tune and log with no knock even in 100deg temps...I'm running at 11.7/1 AFR data logged with my LM1 wideband..
Stock LS1 compression, 20 degs of advance at WOT, I use HP tuners to tune and log with no knock even in 100deg temps...I'm running at 11.7/1 AFR data logged with my LM1 wideband..
differences between the track and the dyno data.
INTHERED
Drifting
Joined: Oct 2003
Posts: 1,923
Likes: 5
From: San Antonio TX
Originally Posted by INTHERED
Did you datalog the KR and AFR at the track ? I found some major
differences between the track and the dyno data.
INTHERED
differences between the track and the dyno data.
INTHERED
in short if you want to run more boost with the maggie, you can but you need to invest into a good tune.
More Than Zero
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
Not on the ragged edge here either..I'm running .5 psi of boost less than MTO. The base tune was done on the dyno, all other tuning has been done on the street and at the track. At the track I run 21degs because I am logging and playing. On the street I run 19degs just to be safe. But even at 21degs at the track and 97* outside I had no knock running around 11.7/1 AFR. We do have 93 octane gas down here though..
Burning Brakes
Joined: Aug 2003
Posts: 1,070
Likes: 9
From: MARRIOTTSVILLE MD
Originally Posted by chriswtx
Not on the ragged edge here either..I'm running .5 psi of boost less than MTO. The base tune was done on the dyno, all other tuning has been done on the street and at the track. At the track I run 21degs because I am logging and playing. On the street I run 19degs just to be safe. But even at 21degs at the track and 97* outside I had no knock running around 11.7/1 AFR. We do have 93 octane gas down here though.. INTHERED
Le Mans Master
Joined: Feb 2002
Posts: 5,970
Likes: 20
From: San Marcos Texas
Last time at the track, I was running 125mph consistently with 92* degs outside air temps. My 60ft and 1/8 were all over the place though (street tires) I need more practice. We are going back tomorrow night. Hopefully it will be in the high 70* deg area and I can get a better launch...
(street tires) I need more practice. We are going back tomorrow night. Hopefully it will be in the high 70* deg area and I can get a better launch...