Cadillac CTS-V - boost question

hello to everyone out there new to the site and have a ? have an 05 cts-v with maggie boost goes over 6psi close to 10 when on it through fifth gear does anyone know why

Superchargers use rpms to build boost. Does the maggy have a boost by pass valve(waste gate)? Something might me wrong with it.

That's a good thing. What size pulley? Also cooler temps = more boost

Its good if he's tuned for it but if he's getting knock above 6#s then it could be a huge problem.

front pulley 2.8 rear IDK and it was pretty cold last night but none of that matters now its going back to the shop lost fuel pressure tonight also talked to magnison said that could happen every thing is fine hope he's right also made 460rwhp 426rwtq

You can gain a little boost with cold weather but your almost doubling your boost. Awsome numbers, was this with 6 pounds or 10?

6 psi

What other mods do you have? Great numbers BTW. Any pics?

no pics yet will get to it though other mod K&N cold air and a B&M shifter on the way

Awsome.

Superchargers use rpms to build boost.

True, but remember, as RPM increases VE also increases. So the blower is spinning faster, flowing more air, but the motor is also eating a lot more of that air, so boost doesn't necessarily change.

Does the maggy have a boost by pass valve(waste gate)? Something might me wrong with it.

The Magnuson blowers do have a bypass valve, however it doesn't do what you think it does. It is not used for boost control, it is used to bypass the blower under light throttle, thus reducing noise and power demand from the blower, and increasing low throttle, off-boost gas mileage.

A wastegate is a form of boost control for a turbocharger, it would not function on a supercharged car.

I believe you are trying to ask him if it has a bleeder valve, which is a possible form of boost control on a supercharger. Although possible, it isn't needed, and isn't plausible, as you are bleeding off air that you just spent power to compress. And the Magnuson does not have one of these (Nor do any other blowers).

A properly-sized supercharger in good mechanical condition should hold pretty even levels of boost (Within 2psi or so), from 2,000rpm to 6,000rpm on a LS1, with maximum boost coming on around 3,000rpm, right before the cam comes on. It is not normal to have swings of 4psi without any atmospheric changes. This leads me to believe there is something either wrong with your blower or your engine.

How many miles on the blower/engine?
Was the blower new or used?
Who installed it?

You could also be experiencing belt slip. The characteristics of this are different on every application, but it boils down to unstable WOT boost.

car has 49,000 blower is used and has less than 5,000 miles installed by thunder racing they thunder racing told me the same thing that the psi should only move around 2psi and the gague may be off they are replacing the gague now

I'd be inclined to agree with them, that it's the gauge. I haven't heard of the Maggie kits having belt slip issues on the LS1, so I kinda doubted that.

What are they using for fuel pump help? They aren't using the crappy Magna volt system are they? If so - PLEASE upgrade to a KB Boost a pump (BAP).

I've seen a few of these maggie cars poop out on the stock magna boost pump. It is crap.

I was just about to ask that question cause I keep blowin my fuel pump fuse is this why?

I was just about to ask that question cause I keep blowin my fuel pump fuse is this why?

Basically - YES.