kyoytey1693

iTrader: (7)

For some reason I thought the magnacharger kits for the F-body's came with 60lb injectors. Now, I'm not so sure. Can anyone tell me how to look at the actual injectors and figure it out. I would call the people I bought it from but I dont trust them. I am wondering this because I am wanting to put on a smaller blower pulley and I want to make sure that I will have enough injector for 10-12 lbs of boost.

Which leads to my next question. Can the stock fuel pump and magnavolt supply enough fuel for that much boost? I see the gto, corvette and, truck guys running that much boost but I can't tell how they are fueling them.

Also, how much fuel pressure should I have all the time? I assumed under normal driving my fuel pressure would be lower and then spike up once the Magnavolt sees the RPM's rising. Currently I hold 59-60 lbs of pressure all the time.

And my last question. Can anyone tell me what size belt I will need to drop down too if I run a 2.5" blower pulley and stock crank pulley with all accessories? When do you have to worry about overspinning one of these things. No one really seems to talk about that a whole lot.

Damn that was a mouthful!! Sorry for the long post but I had to get all of those thoughts out of my head...

Frost

iTrader: (45)

AFAIK they ship with green-top 42 lb injectors

old motorhead

iTrader: (10)

My front drive came with 42#ers also. I have an in tank Walbro, so I can't help much there. It's good to well over 650 hp. I went to 60# injectors when I swapped to an MP122 blower.

farmdawg

i had a Walbro 340 intank pump on mine and the magnavolt boost-a-pump. I had a Accel 44# injectors and never had a problem running lean or getting too close to max duty cycle of the injectors. Most of the kits for f-bods come with 42# injectors as far as i know. i ran a 2.9 pulley and had 10psi, which according to what I was told by the manufacturer, and the shop I got the kit from is the max efficiency of the 112. If you try to spin it faster to create more boost, it creates too much heat making it ineffective. i had to radius the throttle body swing arm to clear the pulley and allow WOT.

As long as you can maintain 55psi at least under boost you should be fine with the stocker and magnavolt. When these kits first came out, there were a few that finished off the original fuel pump pretty quick, but haven't heard that much about them recently.

If you want to run the smaller pulley for higher boost I would recommend using the larger idler pulley under the tb, I used it and kept the same belt, just let the tensioner pulley keep the belt tight. I only had belt issues on dyno night running it hard and under load for tuning, but it never pitched the belt on me. Many times after that night, I got into boost hard and never had belt slip issues. I kept the stock accessory pulleys on all of the engine accessories as well.

kyoytey1693

iTrader: (7)

Thanks guys. I have never seen or head of the larger idler pulley you are talking about. Can you direct me to where I can find one. I do have green top injectors so I assume those are 42lbs?

Farmdawg you say you had 10lbs of boost w/ a 2.9 pulley. I am making 6-7lbs with a 3.10" pulley. So by my calculation a 2.5" pulley will net me around 11-12 lbs of boost? Does that sound right?

Right now I keep pleanty of fuel pressure. In my opinion I have too much. It's constantly at 59-60lbs. I figured it would be lower under part throttle and cruise. I think this is why my fuel mileage has went to hell. My concern is whether or not the current fuel pump and magnavolt can keep up with that much boost?

kikass_z28

What kind of air/fuel readings are you getting? How does your tune look?

BLOWNBLUEZ06

iTrader: (17)

To help with (or prevent) belt slip, you should consider looking into an overdrive pulley from Innovators West. I know a guy that has been spinning his Maggie 26krpm. 2.5 pulley, overdriving on the back side pulleys, overdrive pulley on the crank. Your fuel pressure is what it should be. That's the way GM set it up from the factory. Tuning and your right foot affect your mileage. Not your fuel pressure.

farmdawg

The larger idler pulley came in my kit, other than that you may have to contact Magnuson for it, or look into some of the vendors on here to find one. ARe you sure you're running a 3.10 and not a 3.4? My 2.9 on my Camaro would get me to ~10-12 according to my boost gauge.

Your fuel pressure is enough to keep up with the boost you have and probably more. If your gas mileage is that bad then maybe you need to have your tune checked, or keep your foot out of the throttle a little more. That blower whine is very addicting, but you must learn to control your "urges".

kyoytey1693

iTrader: (7)

Yes I am positive on the 3.10 pulley. It came with a 3.40 and it was only at 4 lbs of boost. The company I bought it from said they sent the wrong one and shipped me the 3.10 pulley and now I at 6-7 lbs. The 2.5 just came in. I am planning to have it tuned in a few weeks. I still have to change the MAP sensor out. The company I bought mine from doesn't believe in incorporating the MAP in the tune, they do it by RPM. So I am still running their base tune. (*** tards)

Also, did you have to run colder plugs or less gap with yours? I want to change those before I get it tuned.

BLOWNBLUEZ06

iTrader: (17)

TR6 (4177's) .035 gap.

martinls1

iTrader: (9)

I'm running the TR6's on mine. Does the pulley say 3.1" on it? I have a 3.2" pulley and pushing the same amount of boost your are, 6-7....maxes out at 7.5. That 2.5" is going to spin the crap out of that thing.....
keep us updated, I want to get a smaller pulley as well, for 10lbs of boost.

kyoytey1693

iTrader: (7)

Yes it definately says 3.10 on it. I will update in a few weeks when I get it tuned for the new pulley.

farmdawg

I've heard good things about the TR6's....I used to run the 55IX iridiums. I think I still have a set on the shelf in my garage come to think of it. Try the Tr6's, I would stay away from platinums though.