I have a 97 4.6 with a Vortech supercharger. I just installed a boost gauge, the most boost I see is 5 lbs? I have put a 10 lb. pulley and there is no chip yet. Should I be seeing more? Thansk for the help.

 

I would think that if you have a 10lb pully then you should be seeing somewhere around 10psi. Maybe not right on the nose, but close.

I'd check to be sure that you don't have a leak in the connections.

 

I have checked all connections, cant find any leaks. I dont even reack the 5 lbs. until I am near 5000 rpms. Anyone else any thoughts?

 

couple of things:

at what rpm is the pulley rated at 10psi

also , i remember crash stating that the stock vortech kit had to be up-graded to make more boost (a different valve)

 

What other mods have you done to the truck? I've heard where headers will actually cause a reduction in boost levels. Also, are you still using the stock airbox? Perhaps it's causing too much of a restriction?

 

I am using the air filter assembly that came with the kit, it resembles a small K@N filter with a metal shroud on top. Not sure what the pulleys rpm to boost range is. I do know it is smaller than the one the kit came with. Thanks for the ideas, I thing I will try and get the unit some more air through the intake, find a way to put the larger K@N back on.

Keep the ideas coming.

 

i also have the vortech and the filter that comes with it looks like it would be a good size for my lawnmower.
i have thought about taking a cut off wheel on my dremel and removing the inner fender material so that a longer filter could be installed, i havent looked at it that close so i dont know how much area there is or if it would be worth it. i think it would help but i dont think that is your problem. you could take the filter completely off and drive it and see if you see higher boost. a short trip would not hurt anything.

 

Check the compression fittings on your boost gauge. Or there may be a pinched/kinked line. Where is the gauge connected to?Check belt tension. Is there any belt dust?

 

All great ideas, I took the filter off and drove it around a short while, no change in boost. There arent any kinked lines to the gauge, I even hooked the gauge up in the engine compartment to make sure. As far as the belt goes, what a pain in the a**. I have had problems with it slipping in the past, but it doesnt seem to be the problem now. By the way is there a way to add a tensioner to my bracket? The 5.4 came with a tensioner but not the 4.6.

Thanks keep the ideas coming.

 

Just to make sure you have the right size pulley you should have a 3.125in pulley part#2A038-312, this info should be stamped on the pulley.

 

Wantmorespeed did you ever solve you problem?

 

I have done all of the aforementioned things and even made sure of the pulley size. I did however get on it the other day and heard an awful squeal. hmmmm maybe the belt is slipping? The tensioner on this charger sucks. I will try to tighten in today and will post my results. What about the maf, or boost bypass, or? I'm fishing here. This thing is a stock install except for the pulley. Thanks

 

I was about to post that it could be your belt slipping but it seems you have come across that.

When your engine is off, the tensioner should be in the fully compressed position. I have seen on my ATI where, at full boost, the belt stretch due to the load uses up all of the tensioner travel and then since the belt is loose, it usually slips without making any noise.

You may need to go to a shorter belt even if you have to really fight to get it on by loosening an idler or two. This is the only way with the ATI.

 

So what is the best belt out there, does some slip more than others? And about the tensioner, no such thing on the 4.6 from Vortech, just get your crowbar and hold tension and tighten.

 

Everybody raves about the Goodyear Gatorback for solving belt slip problems.

Can't say from personal experience, never felt that I needed one.